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Stellarium User Guide

1. Stellarium Name Other Name s Type Magnitude Location Guide Description Dubhe and Merak The Pointers Stars 1 83 2 36 The two rightmost of the seven Northern hemisphere observers are very stars that form the main shape of fortunate to have two stars that point to The Plough Ursa Major wards Polaris which lie very close to the northern celestial pole Whatever the time of night or season of the year they are al ways an immediate clue to the location of the pole star M31 Messier 31 The An Spiral Galaxy 3 4 Find the three bright stars that con M31 is the most distant object visible to the dromeda Galaxy stitute the main part of the con naked eye and among the few nebulae that stellation of Andromeda From the can be seen without a telescope or power middle of these look toward the ful binoculars Under good conditions it constellation of Cassiopeia appears as a large fuzzy patch of light It is a galaxy containing billions of stars whose distance is roughly three million light years from Earth The Garnet Star Mu Cephei Variable Star 4 25 Avg Cephius lies above the W shape A supergiant of spectral class M with of Cassiopeia The Garnet Star a strong red colour Given it s name by lies slightly to one side of a point Sir William Herschel in the 18th century half way between 5 Cephei and 21 the colour is striking in comparison to it s Cephei blue white neighbours 4 and 5 Lyrae Epsilon Lyrae Double
2. From version 0 10 2 the time zone is taken from the operating system environment 20 4 4 THE CONFIGURATION WINDOW CHAPTER 4 CONFIGURATION Location AR Add to Jist Figure 4 2 Location window To set your location press F6 to open the location window figure 4 2 There are a few ways you can set your location 1 Just click on the map 2 Search for a city where you live using the search edit box at the top right of the window and select the right city from the list 3 Enter a new location using the longitude latitude and other data This will be saved in an ASCII user_locations txt file in the data folder of your user section Once you re happy that the location is set correctly click on the use as default checkbox and close the location window 4 4 The Configuration Window The configuration window contains general program settings and many other settings which do not concern specific display options 21 4 4 THE CONFIGURATION WINDOW CHAPTER 4 CONFIGURATION a a A QIRIR lt lt lt lt a a a S Figure 4 3 The Main and information tabs of the Configuration window The Main tab in the configuration window4 3 provides controls for changing the pro gram language how much information is shown about selected sky objects and provides a button for saving the current program configuration The Information tab is where you can select the amount of information di
3. ee 27 ET WI WS e dc a rd rd e 27 E ele a o a PEA 28 and e ls E 28 da de Ge A o ias as 8 28 Bou Gee he e dee a Gh ase es ee 29 Oe he ok es ra ik tee OR ee da 30 Diol _ Examples e 3 62 004 bi a Awe ee pe Oa 30 CONTENTS CONTENTS a E MA Se e Be Be 31 A is 6 doe 2 fecha eal ies WA R ane bt ie Bodie ee wah weg Bik 31 5 5 1 Running Scripts 2 2 2 2 02 ee eee ee ee eee 31 5 5 2 Installing Scripts 2 ee ee 31 AI 31 5 6 Visual Effects s ets ee uea a a 31 5 6 1 Light Pollution gt s s s eeste reese egn ae 31 NS 33 5 7 1 Single Fish eye Method oo o 33 5 7 2 Single Panorama Method o o 34 5 7 3 Multiple Image Method o 34 5 74 landscape ini location section 36 37 37 37 38 39 39 40 42 43 44 50 65 66 69 bo Od tt e a ek be eA he eS 69 DLI ZONES sae ir da i cg Se ee Bk A ea 69 Meth ee eh e oe we CHEE oa ows 69 i be Ba Be GRA OS Be ate ye be ee ek 69 ce seed chy dors Rong knee Meng ea ayes deity eee es 70 eae ES Se heh Ge be bE ee ls RS 71 D 2 3 1 File Header Record 0 71 A a ti dai 71 rai dra Bow 71 75 A aS ade fe el E 75 EOS The Camera ile iio o A a Be Ard 75 E eB we eth ee Ge 76 ore es 76 ip We a RR EO A 77 nee 78 E 0 10 Making a Fisheye PanoraMa o 80 81 EPEE dan 81 he Elie
4. Option Option Description Parameter help or h none Print a quick command line help message and exit version or v none Print the program name and version information and exit config fileor c config file name Specify the configuration file name The default value is config ind The parameter can be a full path which will be used verbatim or a partial path Partial paths will be searched for inside the regular search paths unless they start with a which may be used to explicitly specify a file in the current directory or similar For example using the option c my_config ini would resolve to the file lt user directory gt my_config ini whereas c my_config ini can be used to explicitly say the file my_config ini in the current working directory restore defaults none If this option is specified Stellarium will start with the default configuration Note The old configuration file will be overwritten user dir path Specify the user data directory screenshot dir path Specify the directory to which screenshots will be saved full screen yes or no Over rides the full screen setting in the config file home planet planet Specify observer planet English name altitude altitude Specify observer altitude in meters longitude longitude Specify latitude e g 53d581 16 651 latitude latitude Specify longitude e g 1d4 27 48
5. Section ID Version Description nebula_magnitude_limit float 0 12 1 Value of limit magnitude of the deep sky objects Description star_magnitude_limit float 0 12 1 Value of limit magnitude of the stars flag_nebula_magnitude _limit bool 0 12 1 Set to true to set limits for showing deep sky objects flag_star_magnitude_limit bool 0 12 1 Set to true to set limits for showing stars flag_extinction_below_horizon bool 0 11 2 Set to true to apply extinction effects to sky below horizon flag_stars bool all Set to false to hide the stars on start up flag_star_name bool all Set to false to hide the star labels on start up flag_planets bool all Set to false to hide the planet labels on start up flag_planets_hints bool all Set to false to hide the planet hints on start up names and circular highlights flag_planets_orbits bool all Set to true to show the planet orbits on start up flag_light_travel_time bool 0 8 0 Set to true to improve accuracy in the movement of the planets by compensating for the time it takes for light to travel This has an impact on performance flag_object_trails bool 0 8 0 Turns on and off drawing of object trails which show the movement of the planets over time flag_nebula bool all Set to false to hide the nebulae on start up flag_nebula_name bool all Set to true to show the nebula labels on start up flag_nebula_long_name bool 0 8 0 Set to true to show the nebula long labels on start up flag_nebula
6. plx 21 int This is the parallax of the star To get the actual value divide by 10000 73 Table D 10 Star Data Record Type 0 at D 2 STAR CATALOGUE FILE FORMAT APPENDIX D STAR CATALOGUE Name Offset Type Size Description x0 int 20 bits This is the position of the star relative to the central point in the star s zone in axis 1 xl 20 bits int 20 bits This is the position of the star relative to the central point in the star s zone in axis 2 dx0 40 bits int 14 bits This is the proper motion of the star in axis 1 dx 54 bits int 14 bits This is the proper motion of the star in axis 2 68 bits unsigned int 7 bits This is the magnitude level in B V colour This value refers to one of 256 discrete steps in the magnitude range for the file mag 75 bits unsigned int 5 bits This is the magnitude level in the V I colour This value refers to one of 256 discrete steps in the magnitude range for the file Table D 12 Star Data Record Type 1 Name Offset Type Size Description x0 int 18 bits This is the position of the star relative to the central point in the star s zone in axis 1 xl 18 bits int 18 bits This is the position of the star relative to the central point in the star s zone in axis 2
7. list landscapes none Print a list of available landscape IDs landscape landscape ID Start using landscape whose ID matches the passed parameter dir name for landscape sky date date The initial date in yyyymmdd format sky time time The initial time in hh mm ss format startup script script name The name of a script to run after the program has started fov angle The initial field of view in degrees projection type ptype The initial projection type e g perspective Table 5 2 Command line options 5 3 Command Line Options Stellarium s behaviour can be modified by providing parameters to the program when it is r pathun via the command line See table 5 2 for a full list 5 3 1 Examples To start Stellarium using the configuration file configuration_one ini situ ated in the user directory use either of these stel stell larium config file configuration_one ini arium c configuration_one ini e To list the available landscapes and then to start using the landscape with the ID ocean 30 5 4 GETTING EXTRA STAR DATA CHAPTER 5 ADVANCED USE stellarium list landscapes stellarium landscape ocean 5 4 Getting Extra Star Data Stellarium is packaged with over 600 thousand stars in the normal program download but much larger star catalogues may be downloaded using the tool which is in the Tools tab
8. first as a command with OLD at the start of the line to help users of the old scripting engine learn how to use the new one core debug Starting Partial Lunar Eclispe script core wait 1 core debug OK let s go Since this guide was written the newer simpler to use landscape type spherical has been implemented This guide should be re written using this simple mechanism submissions very welcome 83 APPENDIX G CREATING SCRIPTS FOR STELLARIUM OLD clear core clear natural LandscapeMgr setFlagLandscape false LandscapeMgr setFlag Atmosphere false LandscapeMgr setFlagFog false core wait 1 OLD date utc 2006 03 14T21 21 32 core setDate 2006 03 14T21 21 32 OLD select planet Moon pointer off core selectObjectByName Moon false StelMovementMgr setFlagTracking true OLD wait duration 2 core wait 2 OLD zoom auto in StelMovementMgr autoZoomIn 2 OLD wait duration 2 core wait 2 OLD timerate rate 500 00001157407407407407 julian days 1 second we want 500 seconds per second good candidate for aforementioned include system function although it s not so bad now we can do arithmetic in scripts core setTimeRate 500 core wait time is a multiple of the TimeRate that is set core wait 60 set the time back to normal StelMovementMegr autoZoomOut 2 core setTimeRate 1 core clear natural set the date b
9. once Look at the clock Time has stopped Click the Decrease time speed button four or five more times Now we re falling back through time at quite a rate about one day every ten seconds Enough time travel for now Wait until it s night time and then click the Real time speed button With a little luck you will now be looking at the night sky 3 1 2 Moving Around the Sky As well as travelling through time Stellarium lets to look around the sky freely and zoom in and out There are several ways to accomplish this listed in table Let s try it Use the cursors to move around left right up and down Zoom in a little using the Page Up key and back out again using the Page Down Press the backslash key and see how Stellarium returns to the original field of view how zoomed in the view is and direction of view B 4 11 3 1 TOUR CHAPTER 3 INTERFACE GUIDE Key Description Cursor keys Pan the view left right up and down Page up Page down Zoom in and out Backslash Y Auto zoom out to original field of view Left mouse button Select an object in the sky Right mouse button Clear selected object Mouse wheel Zoom in and out Space Centre view on selected object Forward slash Auto zoom in to selected object Table 3 4 Controls to do with movement It s also possible to move around using the mouse If you left click and drag somewhere on the sky you can pull the view a
10. DejaVuSans ttf string 0 12 0 Selects the name for base font e g DejaVu Sans continued Section ID Version Description 55 APPENDIX A CONFIGURATION FILE safe_font_file string 0 12 0 Selects the name for font file e g DejaVuSans ttf flag_show_fps bool all Set to false if you don t want to see at how many frames per second Stellarium is rendering flag_show_fov bool all Set to false if you don t want to see how many degrees your field of view is flag_show_script_bar bool 0 7 1 Set to true if you want to have 0 10 0 access to the script bar flag_mouse_cursor_timeout float 0 8 0 set to 0 if you want to keep the mouse cursor visible at all times non 0 values mean the cursor will be hidden after that many seconds of inactivity flag_script_allow_ui bool 0 8 0 When set to false the normal 0 10 0 movement controls will be disabled when a script is playing true enables them flag_show_flip_buttons bool 0 8 2 Enables disables display of the image flipping buttons in the main toolbar see section sec imageflipping flag_show_nebulae_background_button bool 0 10 1 Set to true if you want to have access to the button for enabling disabling back grounds for deep sky objects flag_use_degrees bool 0 12 2 selected_object_info string 0 10 0 Values all short and none Value custom added since version 0 12 0 auto_hide_horizontal_toolbar bool 0 10 1 S
11. The Object Search window provides a convenient way to locate objects in the sky Simply type in the name of an object to find and then click the go button or press return Stellarium will point you at that object in the sky As you type Stellarium will make a list of objects which contain the letter sequence you have typed so far The first of the list of matching objects will be highlighted If you press the TAB key the selection will change to the next item in the list Hitting the RETURN key will go to the currently highlighted object and close the search dialog For example suppose we want to locate Mimas a moon of Saturn After typing the first letter of the name m Stellarium makes a list of objects whose name begins with M Mars Mercury Mimas Miranda Moon The first item in this list Mars is highlighted Pressing return now would go to Mars but we want Mimas We can either press TAB twice to highlight Mimas and then hit RETURN or we can continue to type the name until it is the first only object in the list The Positiont Search window provides a convenient way to enter a user set of coordin ateslocate objects in the sky Simply type in the RA and Dec Coordinates of an object to find and then click the go button or press return Stellarium will point you at that object in the sky Figure 3 6 The search window options and lists The Option Search window B 6 provides a convenient way to locate objects in the s
12. Waning Crescent Table J 6 Phases of the moon c has cleared the neighbourhood around its orbit or within another system i is in orbit around a star or stellar remnants 11 has a mass below the limiting mass for thermonuclear fusion of deuterium and iii is above the minimum mass size requirement for planetary status in the Solar System Moving from the Sun outwards the major planets are Mercury Venus Earth Mars Jupiter Saturn Uranus and Neptune Since the formal definition of a planet in 2006 Pluto has been relegated to having the status of dwarf planet along with bodies such as Ceres and Eris See figure J 4 J 4 1 Terrestrial Planets The planets closest to the sun are called collectively the terrestrial planets The terrestrial planets are Mercury Venus Earth and Mars The terrestrial planets are relatively small comparatively dense and have solid rocky surface Most of their mass is made from solid matter which is mostly rocky and or metal lic in nature J 4 2 Jovian Planets Jupiter Saturn Uranus and Neptune make up the Jovian planets They are much more massive than the terrestrial planets and do not have a solid surface Jupiter is the largest of all the planets with a mass over 300 times that of the Earth The Jovian planets do not have a solid surface the vast majority of their mass being in gaseous form although they may have rocky or metallic cores Because of this they have an av
13. angular size It s useful to know if your handy angles are typical and if not what they are The method here below is just one way to do it feel free to use another method of your own construction Hold your hand at arm s length with your hand open the tips of your thumb and little finger as far apart as you can comfortably hold them Get a friend to measure the distance between your thumb and your eye we ll call this D There is a tendency to over stretch the arm when someone is measuring it try to keep the thumb eye distance as it would be if you were looking at some distant object Without changing the shape of your hand measure the distance between the tips of your thumb and little finger It s probably easiest to mark their positions on a piece of 117 L 3 FIND A LUNAR ECLIPSE APPENDIX L EXERCISES paper and measure the distance between the marks we ll call this d Using some simple trigonometry we can estimate the angular distance 6 Repeat the process for the distance across a closed fist three fingers and the tip of the little finger For example for the author D 72 cm d 21 cm so 0 2 arct Es arctan 144 1 0 1670 2 Remember that handy angles are not very precise depending on your posture at a given time the values may vary by a fair bit L 3 Find a Lunar Eclipse Stellarium comes with two scripts for finding lunar eclipses but can you find one on a different date L 4 Find a Sola
14. data ssystem ini file The file format follows ini file conventions Each section in the file represents the data for one planetary body Each section has values as described in table 5 9 Orbital calculations for the major planets is handled by sophisticated custom algorithms and are accurate for a comparatively long time For asteroids and comets the calculations are not as accurate and the data in ssystem ini for these bodies should be updated period ically every year or two At present this must be done manually by editing the ssystem ini file 40 5 10 ADDING PLANETARY BODIES CHAPTER 5 ADVANCED USE Name Format Description name string English name of body case sensitive parent string English name of parent body the body which this body orbits e g in the case of our Moon the parent body is Earth radius float Radius of body in kilometers halo boolean Tf true the body will have a halo displayed round it when it is bright enough color r g b Colour of object when rendered as a point Each of r g b is a floating point number between 0 and 1 tex_map string File name of a PNG or JPEG texture file to be applied to the object Texture file is searched for in the textures directory tex_halo string File name of a PNG or JPEG texture file to be used as the halo image if the halo option is set to true tex_b
15. 0 005 1 1 Side5 tex5 0 0 005 1 1 34 5 7 CUSTOMISING LANDSCAPES CHAPTER 5 ADVANCED USE Figure 5 1 Multiple Image Method of making landscapes Side6 tex6 0 0 005 1 1 side 7 tex7 0 0 005 1 1 groundtex guereinsb png ground groundtex 0 0 1 1 fogtex fog png fog fogtex 0 0 1 1 nb_decor_repeat 1 decor_alt_angle 40 decor_angle_shift 22 decor_angle_rotatez 0 ground_angle_shift 22 ground_angle_rotatez 45 fog_alt_angle 20 fog_angle_shift 3 draw_ground_first 1 Where name is the name that will appear in the landscape tab of the configuration window for this landscape type should be old_style for the multiple image method nbsidetex is the number of side textures for the landscape tex0 tex lt nbsidetex 1 gt are the side texture file names These should exist inthe textures landscapes directory in PNG format nbside is the number of side textures 35 5 7 CUSTOMISING LANDSCAPES CHAPTER 5 ADVANCED USE sideO side lt nbside 1 gt are the descriptions of how the side textures should be arranged in the program Each description contains five fields separated by colon characters The first field is the ID of the texture e g tex0 the remaining fields are the coordinates used to place the texture in the scene groundtex is the name of the ground texture file ground is the description of the projection of the ground texture in the scene fogtex is the
16. 0 1 0 1 0 for white ecliptic_J2000_color float all Sets the colour of the ecliptic grid R G B J2000 in RGB values where 1 is the maximum e g 1 0 1 0 1 0 for white meridian_color float 0 11 0 Sets the colour of the meridian line in R G B RGB values where 1 is the maximum e g 1 0 1 0 1 0 for white horizon_color float all Sets the colour of the horizon line in R G B RGB values where 1 is the maximum e g 1 0 1 0 1 0 for white const_lines_color float all Sets the colour of the constellation R G B lines in RGB values where 1 is the maximum e g 1 0 1 0 1 0 for white const_names_color float all Sets the colour of the constellation R G B names in RGB values where 1 is the maximum e g 1 0 1 0 1 0 for white const_boundary_color float all Sets the colour of the constellation R G B boundaries in RGB values where 1 is the maximum e g 1 0 1 0 1 0 for white nebula_label_color float all Sets the colour of the nebula labels in R G B RGB values where 1 is the maximum e g 1 0 1 0 1 0 for white nebula_circle_color float all Sets the colour of the circle of the R G B nebula labels in RGB values where 1 is the maximum e g 1 0 1 0 1 0 for white star_label_color float all Sets the colour of the star labels in R G B RGB values where 1 is the maximum e g 1 0 1 0 1 0 for white star_circle_color float 0 8 0 Sets the colour of the circle of the star R G B labels in RGB values where 1 is the maximum e g 1 0 1 0 1 0 for white cardinal_colo
17. 0 4 5 7 4 landscape ini location section An example location section location planet Earth latitude 48d10 9 707 longitude 11d36 32 508 altitude 83 Where planet Is the English name of the solar system body for the landscape latitude Is the latitude of site of the landscape in degrees minutes and seconds Positive values represent North of the equator negative values South of the equator 36 5 8 ADDING NEBULAE IMAGES CHAPTER 5 ADVANCED USE longitude Is the longitude of site of the landscape Positive values represent East of the Greenwich Meridian on Earth or equivalent on other bodies Negative values rep resent Western longitude altitude Is the altitude of the site of the landscape in meters 5 8 Adding Nebulae Images Extended objects are those which are external to the solar system and are not point sources like stars Extended objects include galaxies planetary nebulae and star clusters These objects may or may not have images associated with them Stellarium also comes with a catalogue of 13 224 extended objects containing the combined NGC and IC catalogues with images of over 100 Prior to version 0 10 x to add a new extended object and allow a display of a texture of that object it was necessary add an entry inthe nebulae default ngc2000 dat file with the details of the object where is either the installation directory or the user directory See section 5 8 1 fo
18. 0 8 0 Sets the colour of the equatorial gride in RGB R G B values where is the maximum e g 1 0 1 0 1 0 for white equator_color float 0 8 0 Sets the colour of the equatorial line in RGB R G B values where is the maximum e g 1 0 1 0 1 0 for white ecliptic_color float 0 8 0 Sets the colour of the ecliptic line in RGB R G B values where is the maximum e g 1 0 1 0 1 0 for white meridian_color float 0 8 0 Sets the colour of the meridian line in RGB R G B values where is the maximum e g 1 0 1 0 1 0 for white const_lines color float 0 8 0 Sets the colour of the constellation lines in R G B RGB values where is the maximum e g 1 0 1 0 1 0 for white const_names_color float 0 8 0 Sets the colour of the constellation names in R G B RGB values where is the maximum e g 1 0 1 0 1 0 for white const_boundary_color float 0 8 0 Sets the colour of the constellation boundaries R G B in RGB values where 1 is the maximum e g 1 0 1 0 1 0 for white nebula_label_color float 0 8 0 Sets the colour of the nebula labels in RGB R G B values where 1 is the maximum e g 1 0 1 0 1 0 for white 51 APPENDIX A CONFIGURATION FILE continued Section ID Version Description nebula_circle_color float 0 8 0 Sets the colour of the circle of the nebula labels R G B in RGB values where 1 is the maximum e g 1 0 1 0 1 0 for whit star_label_color float 0 8 0 Sets the colour of the star la
19. 87 92 B3 P5 007 Betelgeuse 103 Polaris 98 Proxima Centuri Sadalmelik Sirius 103 status bar stellar parallax stereographic projection sub system Sun 92 9598 super giants 104 supernova remnant 109 system clock 11 telescope control terrestrial planets 107 texture files time time rate time zone 66 tool bar main 13 20 93 94 time twinkling Tycho catalogue 111 units Uranus 65 User Directory 69 user directory 27429 variable stars 106 Algol vector Venus visual effects VSOP87 65 INDEX INDEX white dwarfs 104 window language tab location tab find 15 help 16 location search 15 zenith zones zoom 127
20. Adams pointed out in the Hitchhiker s Guide to the Galaxy I Space is big You just won t believe how vastly hugely mind bogglingly big it is I mean you may think it s a long way down the road to the chemist s but that s just peanuts to space I Astronomers use a variety of units for distance that make sense in the context of the mind boggling vastness of space Astronomical Unit AU This is the mean Earth Sun distance Roughly 150 million kilo metres 1 49598 x 108km The AU is used mainly when discussing the solar system for example the distance of various planets from the Sun Light year A light year is not as some people believe a measure of time It is the dis tance that light travels in a year The speed of light being approximately 300 000 kilometres per second means a light year is a very large distance indeed working out at about 9 5 trillion kilometres 9 46073 x 10 km Light years are most frequently used when describing the distance of stars and galaxies or the sizes of large scale objects like galaxies nebulae etc Parsec A parsec is defined as the distance of an object that has an annual parallax of 1 second of arc This equates to 3 26156 light years 3 08568 x 10 km Parsecs are most frequently used when describing the distance of stars or the sizes of large scale objects like galaxies nebulae etc 95 1 3 UNITS APPENDIX I ASTRONOMICAL CONCEPTS 13 2 Time The length of a day is def
21. D 2 3 1 File Header Record The File Header Record describes file wide settings It also contains a magic number which servers as a file type identifier See table D 6 D 2 3 2 Zone Records The Zone Records section of the file lists the number of star records there are per zone The number of zones is determined from the level value in the File Header Record as described in section D 1 1 The Zones section is simply a list of integer values which describe the number of stars for each zone The total length of the Zones section depends on the number of zones See table D 8 D 2 3 3 Star Data Records After the Zones section the actual star data starts The star data records themselves do not contain the zone in which the star belongs Instead the zone is inferred from the position of the record in the file For example if the Zone Records section of the file says that the first 100 records are for zone 0 the next 80 for zone 1 and so on it is possible to infer the zone for a given record by counting how many records have been read so far The actual record structure depends on the value of the Data Type as found in the File Header Record See tables D 10 D 12hnd D 14 for record structure details It should be noted that although the positional data loses accuracy as one progresses though the Star Record Types this is compensated for by the face that the number of zones 1s much higher for the files where the smaller precision positio
22. Screenshots You can save what is on the screen to a file by pressing CTRL s Screenshots are taken in bmp format and have filenames something like this stellarium 000 bmp stellariuim 001 bmp 43 5 13 PLUG INS CHAPTER 5 ADVANCED USE the number increments to prevent over writing existing files Stellarium creates screenshots in different directories depending in your system type see section 5 13 Plug Ins Stellarium has been greatly expanded since version 0 10 2 with compiled static plug ins By this method many add ons for specific use can be added without modifying the program core There are many plug ins now available that can be loaded at startup and be available within the program as each plug in is loaded an icon is placed in the bottom menu bar At present Version 0 12 3 there are 17 plug ins bundled with the release version of Stellarium These include AngleMeasure Measures the angle and distance between objects on the visible screen Figure 5 2 Angle Measure plug in Enable the tool by clicking the tool bar button or by pressing control A A message will appear at the bottom of the screen to tell you that the tool is active Drag a line from the first point to the second point using the left mouse button To clear the measurement click the right mouse button To deactivate the angle measure tool press the tool bar button again or press control A on the keyboard CompassMarks places a scale of degree
23. Star 47 Look near to Vega Alpha Lyrae In binoculars epsilon Lyrae is resolved into one of the brightest stars in the sky two separate stars Remarkably each of these is also a double star although this will only be seen with a telescope and all four stars form a physical system 114 APPENDIX K SKY GUIDE Stellarium Name Other Name s Type Magnitude Location Guide Description M13 Hercules Cluster Globular 5 8 Located approximately of the way This cluster of hundreds of thousands of Cluster along a line from 40 to 44 Herculis mature stars that appears as a circular cloud using the naked eye or binoculars a large telescope is required to resolve in dividual stars Oddly the cluster appears to contain one young star and several areas that are almost devoid of stars M45 The Pleiades The Open Cluster 1 2 Avg Lies a little under halfway between Depending upon conditions six to 9 of Seven Sisters Aldebaran in Taurus and Almaak in the blueish stars in this famous cluster will Andromeda be visible to someone with average eye sight and in binoculars it is a glorious sight The cluster has more than 500 members in total many of which are shown to be sur rounded by nebulous material in long ex posure photographs Algol The Demon Star Variable Star 3 0 Avg Halfway between Aldebaran in Once every three days or so Algol s bright Beta Persei Taurus and the middle star of the ness changes from 2 1
24. Stellarium program However this only rarely happens so a little bit of tweaking of the json worldcoords will be needed to get a perfect match Select the telescope equatorial mode This will show the area with north up Select each corner in sequence and make small changes to the coordinates Re start Stellarium each time and check if you have moved the right direction Continue with each corner until all the stars match With a little bit of practice this will be done in about 10 minutes 91 Appendix I Astronomical Concepts This section includes some general notes on astronomy in an effort to outline some concepts that are helpful to understand features of Stellarium Material here is only an overview and the reader is encouraged to get hold of a couple of good books on the subject A good place to start is a compact guide and ephemeris such as the National Audubon Society Field Guide to the Night Sky 3 Also recommended is a more complete textbook such as Universe 4 There are also some nice resources on the net like the Wikibooks Astronomy book 5 I 1 The Celestial Sphere The Celestial Sphere is a concept which helps us think about the positions of objects in the sky Looking up at the sky you might imagine that itis a huge dome or top half of a sphere and the stars are points of light on that sphere Visualising the sky in such a manner it appears that the sphere moves taking all the stars with it it seems to rotate If w
25. and event loop They are heavily based on Qt features The core which provides generic services and features to the other components The main class is the StelApp singleton which is used everywhere in the code to access other elements The StelApp instance creates all the main core services and modules at initializa tion Example services are sky layer management e g images which have a fixed position in the sky with the StelSkyLayerMgr drawing with StelRenderer etc Two especially important manager classes are the StelModuleMgr and StelCore the former manages the collection of StelModule instances registered in the program see next point for more info on what a StelModule is The latter provides performance critical features for computing coordinate transformation and other mathematical services A collection of StelModule instances which display the main elements of the program such as planets and stars Each StelModule should be registered to the StelModuleMgr Be cause many Stellarium components derive from the StelModule class the main loop is able to treat them generically by calling their standard methods such StelModule update and StelModule draw at each program iteration This also allows other program components to access them by name StelModule can also be loaded dynamically by Stellarium which is the standard way of creating Plugins The Graphical User Interface StelGui It is based on styled Qt widgets which are
26. be show hour angles for object flag_show_magnitude bool 0 11 3 Tf true Stellarium will be show hour angles for object flag_show_name bool 0 11 3 Tf true Stellarium will be show common name for object flag_show_radecj2000 bool 0 11 3 If true Stellarium will be show geocentrical equatorial coordinates J2000 of object flag_show_radecofdate bool 0 11 3 If true Stellarium will be show geocentrical equatorial coordinates of date of object flag_show_size bool 0 11 3 Tf true Stellarium will be show size of object Section custom_time_correction Section ID Version Description coefficients float float float 0 12 1 Coefficients for custom equation of DeltaT ndot float 0 12 1 n dot value for custom equation of DeltaT year integer 0 12 1 Year for custom equation of DeltaT Section files Section ID Version Description removable_media_path string 0 9 0 Path to removable mediaremovable media CD DVD This is usually only used in Digitalis planetariums products scripts_can_write_files bool 0 9 0 Some scripting commands will cause files to be written Unless this option is set to true these scripting commands will fail Section gui Section ID Version Description base_font_size Section integer all Sets the font size Typical value 15 base Saar nats string 0 8 0 Selects the name for font file ie 0 11 4 e g
27. data is available in the landscape ini file initial_brightness float 0 12 1 Set initial brightness for landscapes Typical value 0 01 Section localization Section ID Version Description sky_culture string all Sets the sky culture to use E g western polynesian egyptian chinese lakota navajo inuit korean norse tupi maori aztec sami Description sky_locale string all Sets language used for names of objects in the sky e g planets The value is a short locale code e g en de en_GB app_locale string all Sets language used for Stellarium s user interface The value is a short locale code e g en de en_GB time_zone string 0 10 6 Sets the time zone Valid values system_default or some region location combination e g Pacific Marquesas time_display_format string 0 10 6 Set the time display format mode can be system_default 24h or 12h date_display_format string 0 10 6 Set the date display format mode can be system_default mmddyyyy ddmmyyyy or yyyymmdd ISO8601 Section main Section ID Version Description invert_screenshots_colors bool 0 10 1 If true Stellarium will saving the screenshorts with inverted colors restore_defaults bool 0 10 1 If true Stellarium will be restore default settings at startup screenshot_dir string 0 10 1 Path for saving screenshots version string all Version of Stellarium This parameter using for updating config ini file 58 APPENDIX A CONFIGURATIO
28. determine the distance of the star when the annual parallax is too small to be a reliable guide Extrinsic variables are stars of constant brightness that show changes in brightness as seen from the Earth These include rotating variables or stars whose apparent brightness change due to rotation and eclipsing binaries J 3 Our Moon The Moon is the large satellite which orbits the Earth approximately every 28 days It is seen as a large bright disc in the early night sky that rises later each day and changes shape into a crescent until it disappears near the Sun After this it rises during the day then gets larger until it again becomes a large bright disc again J 3 1 Phases of the Moon As the moon moves round its orbit the amount that is illuminated by the sun as seen from a vantage point on Earth changes The result of this is that approximately once per orbit the moon s face gradually changes from being totally in shadow to being fully illuminated and back to being in shadow again This process is divided up into various phases as described in table J 4 The Major Planets Unlike the stars whose relative positions remain more or less constant the planets seem to move across the sky over time the word planet comes from the Greek for wanderer The planets are like the Earth massive bodies that are in orbit around the Sun Until 2006 there was no formal definition of a planet leading to some confusion about the classifica
29. form RA and Dec of the end points of a line that will be drawn on the screen when the menu item constellation boundaries is ticked in the colour of the line designated in the config ini file F 0 11 6 Constellationart fab This file is used to locate and orientate the constellation figure a png file as described above Each entry uses the three letter number that refences the constellation in the con stellation_names eng fab file followed by a space then the name of the texture Next is the first horizontal vertical pixel count and the Hipparcos star refence followed by the same data for the second and third reference points Each item separated by a space See the contellationart fab file for the western or inuit cultures F 0 11 7 Constellationship fab This file uses the three letter number from the constellation_names eng fab file to each of the constellations followed by a space then the number if coordinate pairs hipparcos star reference to draw lines representing the constellations when the constellation button is active in the colour selected for this line in the config ini file F 0 11 8 Info ini This is a simple file The first line is info and the second line is name name of culture folder 82 Appendix G Creating Scripts for Stellarium by Barry Gerdes and the Stellarium team 2013 08 1941 Although this procedure is based on the Microsoft Windows System the basics will apply to any platform that can ru
30. galaxies 109 Cepheid variable 106 equator 92 Ceres 107 celestial 93 94 clock equator line 124 INDEX INDEX equatorial grid Eris 107 ESA 111 European Space Agency 111 extended object extended set extrinsic 106 faces field of view file configuration configuration misc landscape ini 33 54 fireballs 110 first point of aries 94 fish eye Flamsteed John flip buttons FOV galaxy Galilean satellites 65 geodesic 69 ern TAT Greenwich 94 grid equatorial Halley Edmund 108 Hertzsprung Ejnar Hipparchus Hipparcos 94 103 catalogue experiment horizon icosahedron image files 39 installation directory interstellar clouds intrinsic irregular galaxies 109 Jovian id 107 JPEG Jupiter ell landscape 281 34 landscape ID landscapes language Latitude 66 latitude 93 94 114 117 lenticular galaxies 109 125 light pollution light year 95 location 20 29 92 Longitude 66 longitude Apa Luminosity 97 luminosity 104 1106 luminosity class M31 07 magellanic cloud 111 magnitude JUNE 96 absolute apparent 01 103 main sequence map var SSO Mercury meridian line Messier 111 Messier Charles 111 Meteor 110 meteor craters 110 meteor shower 6 Meteorites 110 Meteoroids Milky Way 67 milli ar
31. in such a way that it may be shone onto a small planet arium dome making a cheap planetarium projection system Disc viewport This option limits masks the main view producing the effect of a telescope eyepiece It is also useful when projecting Stellarium s output with a fish eye lens planetarium projector Gravity labels This option makes labels of objects in the main view align with the nearest horizon This means that labels projected onto a dome are always alighned properly Auto zoom out returns to initial field of view When enabled this option changes the be haviour of the zoom out key so that it resets the initial direction of view in addition to the field of view Plug ins Figure 4 5 The Scripts and Plug Ins Tools tabs of the Configuration window The Scripts tat 4 5 allows the selection of pre assembled scripts bundled with stellarium that can be run This list can be expanded in your user area with your own scripts as required e When a scipt is selected it can be run by pressing the arrow button and stopped with the stop button With some scripts the stop button is inhibited until the script is finished e Scripts that use sound will need a version of stellarium compiled at compile time with sound enabled It must be pointed out here that sound when enabled depends on the sound capabilities of you computer plarform and may not work e Scripts that contain Video clips will need a suitable video player that enabl
32. most complex part of the process and requires a program that can produce transparency to parts of your picture commonly called an alpha channel Two programs I know of will do this The very expensive and sophisticated Adobe Photoshop and a freebee called The Gimp I used photoshop to cut the full panorama into 1024 x 1024 textures because it was the easiest to do accurate cutting I first used Photoshop to produce the alpha channel because it was the only way I knew but I now use the GIMP as it is much easier to process the individual textures than removing the background from the full panorama 1 Load the Ist section into TheGimp 2 Next create a new empty picturel024 x 1024 and use the advanced tab to make the background color transparency Copy the original texture onto this new picture base 76 APPENDIX E CREATING A PERSONALISED LANDSCAPE FOR STELLARIUM so that it exactly fits the frame then select layer from the menu and press anchor This will create a new picture with with an alpha channel By using the select by color and lasso etc cut out the parts you don t want this will expose the checkerboard background When you are happy with the removal save the texture in png format to preserve the alpha layer 3 Do the same with the remaining pictures 4 Make a new directory for the landscape This should be a sub directory of either the lt user directory gt landscapes or lt installation gt landscapes dir ectory The
33. name of the texture file for fog in this landscape fog is the description of the projection of the fog texture in the scene nb_decor_repeat is the number of times to repeat the side textures in the 360 panorama decor_alt_angle is the vertical angular size of the textures i e how high they go into the sky decor_angle_shift vertical angular offset of the scenery textures at which height are the side textures placed decor_angle_rotatez angular rotation of the scenery around the vertical axis This is handy for rotating the landscape so North is in the correct direction ground_angle_shift vertical angular offset of the ground texture at which height the ground texture is placed ground_angle_rotatez angular rotation of the ground texture around the vertical axis When the sides are rotated the ground texture may need to me rotated as well to match up with the sides fog _alt_angle vertical angular size of the fog texture how fog looks fog_angle_shift vertical angular offset of the fog texture at what height is it drawn draw_ground_first if 1 the ground is drawn in front of the scenery i e the side textures will overlap over the ground texture Note that the name of the section in this case guereins must be the landscape ID i e the same as the name of the directory where the Landscape ini file exists A step by step account of the creation of a custom landscape has been contributed by Barry Gerdes See Appendix E
34. of the Configuration dialog 5 5 Scripting In version 0 10 2 of Stellarium includes the beginnings of a new scripting engine The new scripting engine is still in development there are missing features and probably a few bugs However most of the deficiencies have been fixed by version 0 12 3 except for the automatic recording feature 5 5 1 Running Scripts To run a script open the Configuration dialog and go to the Scripts tab A list of available scripts will be displayed in the list box on the left side When a script name is selected by clicking on it details about that script will be shown in the panel on the right side To run the selected script click the run script button looks like a play button found on a CD or DVD player 5 5 2 Installing Scripts To install a script copy the script and any related filesto lt User Data Directory gt scripts 5 5 3 Writing Scripts Until the new script engine complete documentation will not be added to the user guide In the mean time the following resources may be helpful e API Documentation Scroll down to see the scripting overview with links to the scripting core object member functions e The scripts in the Subversion repository Many of these do not get installed because they are not so useful proof of concept things but there are quite a few in there which would be helpful for someone trying to learn about the new scripting engine e The stellarium pubdevel mailing l
35. of key bindings3 7 Date and Time Add 1 sidereal day Alt Add 1 sidereal week Alt Add 1 sidereal month Alt Shift Add 1 sidereal year Ctrl Alt Shift Add 1 solar hour Ctrl Add 1 solar week Decrease time speed J Decrease time speed a little Shift J Increase time speed L Increase time speed a little Shift L Pause script execution Ctrl D P Resume script execution Ctrl D R Set normal time rate K Set time rate to zero 7 Set time to now 8 Stop script Execution Ctrl D S Subtract 1 Sidereal day Alt Subtract 1 sidereal week Alt Subtract 1 sidereal month Alt Shift Subtract 1 sidereal year Ctrl Alt Shift Subtract 1 solar day Subtract 1 solar hour Ctrl Subtract 1 solar week Table 3 7 Table of key bindings 16 3 1 TOUR CHAPTER 3 INTERFACE GUIDE Table of key bindings Continue Display Options Atmosphere A Azimuthal grid Z Cardinal points Q Constellation art R Constellation boundaries B Constellation labels V Constellation lines C Ecliptic line Equator line Equatorial grid E Flip screen horizontally Ctrl Shift H Flip screen vertically Ctrl Shift V Fog F Full screen mode F11 Ground G Meridian line Nebulae N Planet labels P Planet orbits O Planet trails Shift T Stars S St
36. pu 82 Sesh he Scouse yee ce oe odo AA Ses 82 F 0 11 3 Star_names tabl 82 F 0 11 4 Constellation_names eng fabl 82 3 CONTENTS CONTENTS F 0 11 5 Constellationboundaries dat 82 F 0 11 6 Constellationart fabl 82 F 0 11 7 Constellationship fabl 82 F O 11 8 Info ini 2 ee 82 G Creating Scripts for Stellarium 83 A de a A ola ee dt a iaa iaa 83 ds a a aos kg a o 84 ih on ea A Pe ee Bok es 87 Sse ida Gigs EN 88 89 TEET 89 EA o aa ee a ede 90 SET ene 90 I Astronomical Concepts 92 E PP e de CERES e RDS 92 A a E E oes 93 1 2 1 Altitude Azimuth Coord nates n n aoa 93 12 2 Right Ascension Declination Coordinates 94 EA AI 95 L3 1 Distancel ee 95 L32 A A a 96 AMBOS e A dr an Ride tos otitis a igs Beck 96 1 3 3 1 Notation es 0 e eee 96 J Astronomical Phenomena 101 DE Lhe Suny 4 2 s ea en Be Rees e Be aR Sh Kae Bw we Ae 101 IEA Wa dec a 1 cs ee ek hy he Re ee aden ed os oto ble Aes 101 J 2 5 Spectral Type amp Luminosity Class J 2 6 Variables 2 1 e 106 Boe nie Sh agree int ee eye te ee ee ee A 106 J 3 1 Phases of the Moon 2 00000 ee eee 106 ghee wid aerators Be Bas Sd Awe ise ah a a GP Bek 106 J 4 1 Terrestrial Plametsl 107 J 4 2 Jovian Planets 2 0 a 10
37. script_console_comment_color float 0 10 5 Sets the colour of the comments in the R G B script console RGB values where 1 is the maximum e g 1 0 1 0 1 0 for white script_console_function_color float 0 10 5 Sets the colour of the functions in the R G B script console RGB values where 1 is the maximum e g 1 0 1 0 1 0 for white script_console_constant_color float 0 10 5 Sets the colour of the constants in the R G B script console RGB values where 1 is the maximum e g 1 0 1 0 1 0 for white Section custom_selected_info Section ID Version Description flag_show_absolutemagnitude bool 0 11 3 Tf true Stellarium will be show absolute magnitude for objects flag_show_altaz bool 0 11 3 Tf true Stellarium will be show horizontal coordinates for objects flag_show_catalognumber bool 0 11 3 Tf true Stellarium will be show catalog designations for objects 54 APPENDIX A CONFIGURATION FILE continued Section ID Version Description flag_show_distance bool 0 11 3 If true Stellarium will be show distance to object flag_show_extral bool 0 11 3 Tf true Stellarium will be show extra info for object flag_show_extra2 bool 0 11 3 Tf true Stellarium will be show extra info for object flag_show_extra3 bool 0 11 3 Tf true Stellarium will be show extra info for object flag_show_hourangle bool 0 11 3 Tf true Stellarium will
38. the landscape tab of the config uration window and can be selected as required E 0 8 Making a Spherical Panorama A simpler method of making a panorama is to use the sperical method These can be made using the program Autostitch to create the full landscape in one large texture The big advantage of the spherical panorama is that it does not need a ground panel However the drawback with the Spherical panorama is that few computer video cards will reproduce a panorama larger than 4096 x 2048 pixels and many will not do better than 2048 x 1024 pixels 77 APPENDIX E CREATING A PERSONALISED LANDSCAPE FOR STELLARIUM Figure E 3 Sphrerical Panorama The Autostitch program is quite easy to use Make sure your panorama shots take the ground almost up to your feet using the lowest aperture possible to ensure a large depth of focus and follow the instructions in the readme file When the panorama is finished it will be in jpg format It will need to be converted to a png with transparent background alpha layer and have the sky removed This is done in TheGimp as in the multipanel type When the sky is removed make sure you save the landscape in png format The drawback with the Spherical panorama is that few computer video cards will repro duce a panorama larger than 4096 x 2048 pixels in Stellarium and many will not do better than 2048 x 1024 pixels My computer will only do 2048 by 1024 If I try to load a larger type I just g
39. the proper filters By far the safest way to observe the Sun it to look at it on a computer screen courtesy of Stellarium J 2 Stars The Sun is just one of billions of stars Even though many stars have a much greater ab solute magnitude than the Sun the give out more light they have an enormously smaller apparent magnitude due to their large distance Stars have a variety of forms different sizes brightnesses temperatures and colours Measuring the position distance and attrib utes of the stars is known as astrometry and is a major part of observational astronomy J 2 1 Multiple Star Systems Many stars have a stellar companions As many as six stars can be found orbiting one another in close association Such associations are known a multiple star systems binary systems being the most common with two stars Multiple star systems are more common than solitary stars putting our Sun in the minority group Sometimes multiple stars orbit one another in a way that means one will periodically eclipse the other These eclipsing binaries or Algol variables 101 J 2 STARS APPENDIX J ASTRONOMICAL PHENOMENA Figure J 1 The constellation of Ursa Major J 2 2 Optical Doubles amp Optical Multiples Sometimes two or more stars appear to be very close to one another in the sky but in fact have great separation being aligned from the point of view of the observer but of different distances Such pairings are known as optical
40. the public It is requested but not required that you contact the authors of the Document well before redistributing any large number of copies to give them a chance to provide you with an updated version of the Document 4 MODIFICATIONS You may copy and distribute a Modified Version of the Document under the conditions of sections 2 and 3 above provided that you release the Modified Version under precisely this License with the Modified Version filling the role of the Document thus licensing distribution and modification of the Modified Version to whoever possesses a copy of it In addition you must do these things in the Modified Version A Use in the Title Page and on the covers if any a title distinct from that of the Document and from those of previous versions which should if there were any be listed in the History section of the Document You may use the same title as a previous version if the original publisher of that version gives permission B List on the Title Page as authors one or more persons or entities responsible for authorship of the modifications in the Modified Version together with at least five of the principal authors of the Document all of its principal authors if it has fewer than five unless they release you from this requirement C State on the Title page the name of the publisher of the Modified Version as the publisher D Preserve all the copyright notices of the Document E Add an appropriat
41. time values system default takes the format from the computer settings or it is possible to select 24 hour or 12 hour clock modes 2 7 Date Display Format Change how Stellarium formats date values system default takes the format from the computer settings or it is possible to select yyyymmdd ddmmyyyy or mmddyyyy modes 3 General menu group 3 1 Sky Culture Select the sky culture to use changes constellation lines names artwork 3 2 Sky Language Change the language used to describe objects in the sky Stars menu group 4 1 Show Turn on off star rendering 66 APPENDIX C TUI COMMANDS 4 2 Star Magnitude Multiplier Can be used to change the brightness of the stars which are visible at a given zoom level This may be used to simulate local seeing conditions the lower the value the less stars will be visible 4 3 Maximum Magnitude to Label Changes how many stars get labelled according to their apparent magnitude if star labels are turned on 4 4 Twinkling Sets how strong the star twinkling effect is zero is off the higher the value the more the stars will twinkle 5 Colors menu group 5 1 Constellation Lines Changes the colour of the constellation lines 52 Constellation Names Changes the colour of the labels used to name stars 53 Constellation Art Intensity Changes the brightness of the constella
42. to Magnitude stars are drawn with a size based on their apparent magnitude When set to Point all stars are drawn with the same size on the screen 6 5 Magnitude Sizing Multiplier Changes the size of the stars when Object Sizing Rule is set to Magnitude 6 6 Milky Way intensity Changes the brightness of the Milky Way texture 6 7 Maximum Nebula Magnitude to Label Changes the magnitude limit for labelling of nebulae 6 8 Zoom Duration Sets the time for zoom operations to take in seconds 6 9 Cursor Timeout Sets the number of seconds of mouse inactivity before the cursor vanishes 67 APPENDIX C TUI COMMANDS 6 10 Setting Landscape Sets Location If Yes then changing the landscape will move the observer to the location for that landscape if one is known Setting this to No means the observer loc ation is not modified when the landscape is changed Scripts menu group 7 1 Local Script Run a script from the scripts sub directory of the User Directory or Installation Directory see section 5 1 7 2 CD DVD Script Run a script from a CD or DVD only used in planet arium set ups 8 Administration menu group 8 1 Load Default Configuration Reset all settings according to the main configuration file 8 2 Save Current Configuration as Default Save the current settings to the main configuration file 8 3 Shutdown Quit Stellarium 8 4 Update me via Internet Only
43. to the textures json file Figure H 1 Screen display of added nebula textures The first step 1s to take a photo of the object you wish to display in Stellarium as a screen backdrop Then when you have the picture you will need align it so that north is directly up and not inverted side to side or up and down as can happen with photos taken with a diagonal mirror in the path Next you will need to crop the picture setting the main feature at the centre and making the cropped size a factor of 2n eg 64 128 256 512 or 1024 pixels square When cropping make sure you leave at least five prominent background stars The next step is to process your photo to make the background black black This will ensure that your background will meld with the Stellarium background and not be noticed Suitable programs to do all this are TheGimp free in keeping with the Stellarium spirit or Photoshop if you can afford it When you have your prepared image you will need to plate solve it using at least 5 known GSC stars that can be identified That is why the cropping with plenty of stars was necessary When the plate is solved you will need to find the J2000 coodinates of the corners and convert them to decimal values to form the world coordinates in the tex tures json file 89 APPENDIX H ADDING EXTRA DEEP SKY PHOTOS TOR STELLARIUM Decmal entry Segle entry Decimal to RADEC Instructora About Fe sen O a RA DEC cana ae sal AA tomsenf ff Nore r
44. typically require changing the actual title 9 TERMINATION You may not copy modify sublicense or distribute the Document except as expressly provided for under this License Any other attempt to copy modify sublicense or distribute the Document is void and will automatically terminate your rights under this License However parties who have received copies or rights from you under this License will not have their licenses terminated so long as such parties remain in full compliance 10 FUTURE REVISIONS OF THIS LICENSE The Free Software Foundation may publish new revised versions of the GNU Free Documentation License from time to time Such new versions will be similar in spirit to the present version but may differ in detail to address new problems or concerns See http www gnu org copyleft Each version of the License is given a distinguishing version number If the Document specifies that a particular numbered version of this License or any later version applies to it you have the option of following the terms and conditions either of that specified version or of any later version that has been published not as a draft by the Free Software Foundation If the Document does not specify a version number of this License you may choose any version ever published not as a draft by the Free Software Foundation 121 Appendix N Acknowledgements Primary author Sky guide exercise ideas Celestial sphere diagrams numerou
45. used in planetarium set ups 8 5 Set Ul Locale Change the language used for the user interface 68 Appendix D Star Catalogue This document describes how Stellarium records it s star catalogues and the related file formats D 1 Stellarium s Sky Model D 1 1 Zones The celestial sphere is split into zones which correspond to the triangular faces of a geodesic sphere The number of zones faces depends on the level of sub division of this sphere The lowest level 0 is an icosahedron 20 faces subsequent levels L of sub division give the number of zones n as n 20 44 Stellarium uses levels 0 to 7 in the existing star catalogues Star Data Records contain the position of a star as an offset from the central position of the zone in which that star is located thus it is necessary to determine the vector from the observer to the centre of a zone and add the star s offsets to find the absolute position of the star on the celestial sphere This position for a star is expressed as a 3 dimensional vector which points from the observer at the centre of the geodesic sphere to the position of the star as observed on the celestial sphere D 2 Star Catalogue File Format D 2 1 General Description Stellarium s star catalogue data is kept in the stars default sub directory of the Installation Directory and or User Directory see section 5 Ip The main catalogue data is split into several files stars_0_0v0_3 cat
46. users home directory i e stellarium screenshot save directory Screenshots are saved to the users home directory 5 1 4 Directory Structure Within the installation directory and user directory defined in section 5 1 files are ar ranged in the following sub directories landscapes contains data files and textures used for Stellarium s various landscapes Each landscape has it s own sub directory The name of this sub directory is called the landscape ID which is used to specify the default landscape in the main configura tion file Windows Vista users who do not run Stellarium with administrator priviliges should adjust the shortcut in the start menu to specify a different directory for screenshots as the Desktop directory is not writable for normal progams The next release of Stellarium will include a GUI option to specify the screenshot directory 28 5 2 THE MAIN CONFIGURATION FILE CHAPTER 5 ADVANCED USE skycultures contains constellations common star names and constellation artwork for Stellarium s many sky cultures Each culture has it s own sub directory in the sky cultures directory nebulae contains data and image files for nebula textures In future Stellarium will be able to support multiple sets of nebula images and switch between them at runtime This feature is not implemented for version 0 9 1 although the directory structure is in place each set of nebula textures has it s own sub di
47. 1 NOMAD stars_6_2v0_0 cat 2 8 bytes 6 26 615 233 NOMAD stars_7_2v0_0 cat 2 8 bytes 7 57 826 266 NOMAD stars_8_2v0_0 cat 2 8 bytes T 116 923 084 NOMAD Table D 2 Stellarium s star catalogue files For a given catalogue file there may be one of three formats for the actual star data The variation comes from the source of the data the larger catalogues of fainter stars providing less data per star than the brighter star catalogues See tables D 2 and for details D 2 2 File Sections The catalogue files are split into three main sections as described in table D 4 70 D 2 STAR CATALOGUE FILE FORMAT APPENDIX D STAR CATALOGUE Section Offset Description File Header 0 Contains magic number geodesic subdivision level and Record magnitude range Zone Records 32 A list of how many records there are for each zone The length of the zones section depends on the level value from the header Star Data 32 4n This section of the file contains fixed size star records as Records described below Records do not contain zone information which must be inferred by counting how many records have been read so far and switching zones when enough have been read to fill the number of stars for the zone as specified in the zones section above The value of n used in the offset description is the number of zones as described above Table D 4 File sections D 2 3 Record Types
48. 12 1024x1024 pixels It uses the pixel coordinates of three significant points in the texture that correspond to stars in the Hipparcos catalogue When drawing a picture to represent a constellation it will help if the three significant stars are used as a grid to do the drawing on so that the feature they represent will be orientated correctly Do the drawing on a black background where the black will be interpreted as full trans parency by the stellarium painting instructions A good program to read off the pixel cordinates easily is TheGimp a free program It will also allow the pictire to be saved in the png format F 0 11 3 Star_names fab This file will contain a separate line for each star you wish to name referenced to a Hip parcos number followed by l_ thestarname see the file star_names fab in the western skyculltre F 0 11 4 Constellation_names eng fab This file contains a separate line for each named constellation The first item in the entry is a three letter number used as a reference for the constellation followed by two spaces two quotation marks then _ a name in english and so on until all the constellations have a name F 0 11 5 Constellationboundaries dat This file will be an empty file unless the constellations are defined as areas of the sky such as in the western skyculture where the sky is divided into boxes either in regular or complex shapes Each entry contains the coordinates in decimal
49. 33 easily visible with averted vision zodiacal light striking in spring and autumn color still visible nearer surroundings vaguely visible Rural suburban transition green yellow 6 1 6 5 Light pollution domes visible in various directions over the horizon zodiacal light is still visible but not even halfway extending to the zenith at dusk or dawn Milky Way above the horizon still impressive but lacks most of the finer details M33 a difficult averted vision object only visible when higher than 55 clouds illuminated in the directions of the light sources but still dark overhead surroundings clearly visible even at a distance Suburban sky orange 5 6 6 0 Only hints of zodiacal light are seen on the best nights in autumn and spring Milky Way is very weak or invisible near the horizon and looks washed out overhead light sources visible in most if not all directions clouds are noticeably brighter than the sky Bright suburban sky red 5 1 5 5 Zodiacal light is invisible Milky Way only visible near the zenith sky within 35 from the horizon glows grayish white clouds anywhere in the sky appear fairly bright surroundings easily visible M33 is impossible to see without at least binoculars M31 is modestly apparent to the unaided eye Suburban urban transition red 5 0 at best Entire sky has a grayish white hue strong light sources evident in all directions Milky W
50. 36 bits unsigned int 7 bits This is the magnitude level in B V colour This value refers to one of 256 discrete steps in the magnitude range for the file mag 43 bits unsigned int 5 bits This is the magnitude level in the V I colour This value refers to one of 256 discrete steps in the magnitude range for the file Table D 14 Star Data Record Type 2 74 Appendix E Creating a Personalised Landscape for Stellarium by Barry Gerdes 01 08 2013 This document describes hown to create a personalised landscape E 0 4 Making a Multi panel Panorama Figure E 1 360 panorama This is the only way to get a high resolution panorama and although this procedure is based on the Microsoft Windows System the basics will apply to any platform that can run the programs mentioned or similar programs on the preferred system If you want a high resolution this is the only method to use The first thing needed for a personalised landscape to superimpose on the horizon dis play is a 360 panorama with a transparent background To make this you will need the following e A digital camera on a tripod or stable platform e A program to convert the pictures into a 360 panorama e A program to remove the background and convert the panorama into about 8 square pictures in PNG format for insertion into Stellarium as the sides and if possible a similar square picture of the base you are standing on to f
51. 7 JS The Minor Planets 2 o oo a 108 03 1 Asteroids oa e 2 ke ee oe eG ewe A 108 J 5 2 Comets rea serer as par e ep e e 108 J6 Galaxies o oi ba Soke a he wee Shee hE e e lt 108 J 7 The Milky Way s se mahesa maga op pioka e elp e i e a a 109 CONTENTS CONTENTS WES INe bUIaE ios ess Bac es a a e Rs 109 J9 Meteoroids ira ds a ae ae Be I dei a 109 E BaD aac ee aot 110 J 10 1 Solar Eclipses 2 2 o e 110 J 10 2 Lunar Eclipses o o 110 3 11 Catalopues lt lt sacs be a Re Eee a a 110 TIT Hipparcos arc ka Bee Dae ko AS BAGS dw A 111 J 11 2 The Messier ObjectS o e 111 J 12 Observing HINtS o e e e 112 J13 Handy Angles cesar se E eee ER A 112 K Sky Guide 114 L Exercises 117 L 1 Find M31 in BimocularsS ee ee 117 LLT Simulation oc os EAR ESE o REE DAG Ed diae 117 MW 2 For Real a se dan a oe A om Gol oe bod oe eS Ss 117 L 2 Handy Angles o e eee ee ee 117 L 3 Find a Lunar Eclipse sce cea co apa eee Re A 118 L 4 Finda Solar Eclipse o 118 M_GNU Free Documentation License 119 N Acknowledgements 122 Bibliography 123 Chapter 1 Introduction Stellarium is a software project that allows people to use their home computer as a virtual planetarium It calculates the positions of the Sun and Moon planets an
52. N FILE Section navigation Section ID Version Description preset_sky_time float all Preset sky time used by the dome version Unit is Julian Day Typical value 2451514 250011573 startup_time_mode string all Set the start up time mode can be actual start with current real world time or Preset start at time defined by preset_sky_time flag_enable_zoom_keys bool all Set to false if you want to disable the zoom flag_manual_zoom bool all Set to false for normal zoom behaviour as described in this guide When set to true the auto zoom feature only moves in a small amount and must be pressed many times flag_enable_move_keys bool all Set to false if you want to disable the arrow keys flag _enable_mouse_navigation bool all Set to false if you want to disable the mouse navigation init_fov float all Initial field of view in degrees typical value 60 init_view_pos float all Initial viewing direction This is a vector with x y z coordinates x being N S S ve y being E W E ve z being up down up ve Thus to look South at the horizon use 1 0 0 To look Northwest and up at 45 use 1 1 1 and so on auto_move_duration float all Duration for the program to move to point at an object when the space bar is pressed Typical value 1 4 mouse_zoom float all Sets the mouse zoom amoun
53. PTER 5 ADVANCED USE constellation_names eng fab This file contains a list of names for each constel lation from the three latter abbreviation of the con stellation constellationsart fab This file contains the details of pictorial representa tions of the constellations fields are 1 Constellation abbreviation 2 image filename This will be appended to skycultures lt culturename gt Should include the png extension Note this is case sensitive Star 1 x position in image pixel Star 1 y position in image pixel Star 1 HP catalogue number Star 2 x position in image pixel Star 2 y position in image pixel Star 2 HP catalogue number ANA A DAA Star 3 x position in image pixel 10 Star 3 y position in image pixel 11 Star 3 HP catalogue number constellationship fab Describes the lines for the constellations The fields are 1 Constellation abbreviation 2 Number of lines After this are pairs of HP catalogue numbers which the lines are drawn between info ini Contains the name for this sky culture as it will ap pear in the configuration dialog s language tab star_names fab Contains a list of HP catalogue numbers and com mon names for those stars 5 10 Adding Planetary Bodies Planetary bodies include planets dwarf planets moons comets and asteroids The orbits and physical characteristics of these bodies are described in the
54. Pulsars plugin at startup Quasars bool 0 11 2 If true Stellarium will be load Quasars plugin at startup Satellites bool 0 10 3 If true Stellarium will be load Satellites plugin at startup SolarSystemEditor bool 0 10 6 If true Stellarium will be load Solar System Editor plugin at startup Supernovae bool 0 11 0 If true Stellarium will be load Historical Supernovae plugin at startup TelescopeControl bool 0 10 3 If true Stellarium will be load Telescope Control plugin at startup TextUserInterface bool 0 10 3 If true Stellarium will be load Text User Interface plugin at startup TimeZoneConfiguration bool 0 10 6 If true Stellarium will be load Time Zone plugin at startup Section projection Section ID Version Description type string 0 8 0 Sets projection mode Values perspective equal_area stereographic fisheye cylinder mercator or orthographic string 0 10 0 Sets projection mode Values ProjectionPerspective ProjectionEqualArea ProjectionStereographic ProjectionFisheye ProjectionHammer ProjectionCylinder ProjectionMercator ProjectionOrthographic viewport all How the view port looks Values none disk viewportMask all How the view port looks Values none flag_use_gl_point_sprite bool all flip_horz all flip_vert all 60 APPENDIX A CONFIGURATION FILE Section proxy Section ID Version Descript
55. Stel larium starts 4 5 4 Starlore Tab The Starlore ta4 7 of the View window controls what culture s constellations and bright star names will be used in the main display Some cultures have constellation art Western and Inuit and the rest do not 26 Chapter 5 Advanced Use 5 1 Files and Directories Stellarium has many data files containing such things as star catalogue data nebula im ages button icons font files and configuration files When Stellarium looks for a file it looks in two places First it looks in the user directory for the account which is running Stellarium If the file is not found there Stellarium looks in the installation directo Thus it is possible for Stellarium to be installed as an administrative user and yet have a writable configuration file for non administrative users Another benefit of this method is on multi user systems Stellarium can be installed by the administrator and different users can maintain their own configuration and other files in their personal user accounts In addition to the main search path Stellarium saves some files in other locations for example screens shots and recorded scripts The locations of the user directory installation directory screenshot save directory and script save directory vary according to the operating system and installation options used The following sections describe the locations for various operating systems 5 1 1 Windows installation dir
56. Stellarium User Guide Matthew Gates Version 0 12 4 12th March 2014 Copyright O 2006 2013 Matthew Gates Permission is granted to copy distribute and or modify this document under the terms of the GNU Free Documentation License Version 1 2 or any later version published by the Free Software Foundation with no In variant Sections no Front Cover Texts and no Back Cover Texts A copy of the license is included in the section entitled GNU Free Documentation License Contents 6 8 ER A a a ia 8 2 2 Downloading lt eos 4 sad Po Gee et Gob ewe ee be a 8 23 Installation gt s 34 4 60 4 40206445 4 eed da Se eas 8 DMT Windows s e ia 200 a e Ree ele we ex es 8 fe Bivens hgh Sieh Ue Mice APRA He tines Bene ah dite Boe Bick 8 se ava Ok tacts us ee ave Gee aha ae een 4 9 wir be Ee bab bh ake wa be Bo aoe ba ee 9 3 Interface Guide 10 Bel NOUR A Re eS bow HB Ee AW Bare wy doe He Rice 10 11 11 12 13 13 15 16 16 20 E Ib We MR one ae eR oe A ER a A 20 oR Ge ey Sean eR eee ee es 20 id oe Hee Gah ged Ae et Beis a ger Ale pepe BR 20 fhe Ge ae a ae Ae a on ey ee 21 ef ape a De te cece we aves hee e Sees ok DPS A 24 A a ie des fos Joe eres eve aA sn Gods st 24 4 5 2 Marking Tab o e e o 25 4 5 3 Landscape Tabl o 25 4 54 Starlore Tabl 26 5_ Advanced Use 27 5 1 Files and Directories
57. Values include none and fisheye_to_spheric_mirror minimum_fps integer all Sets the minimum number of frames per second to display at hardware performance permitting maximum _fps integer all Sets the maximum number of frames per second to display at This is useful to reduce power consumption in laptops Section viewing Section ID Version Description atmosphere_fade_duration float 0 8 0 Sets the time it takes for the atmosphere to fade when de selected flag_constellation_drawing bool all Set to true if you want to see the constellation line drawing on start up flag_constellation_name bool all Set to true if you want to see the constellation names on start up flag_constellation_art bool all Set to true if you want to see the constellation art on start up flag_constellation_boundaries bool 0 8 0 Set to true if you want to see the constellation boundaries on start up flag_constellation_isolate_selected bool all When set to true constellation lines boundaries and art will be limited to the constellation of the selected star if that star is on one of the constellation lines flag_constellation_pick bool 0 6 2 Set to true if you only want to see the 0 7 1 line drawing art and name of the selected constellation star flag_azimutal_grid bool all Set to true if you want to see the azimuthal grid on start up flag_equatorial_grid bool all Set to true if you want to see the equatorial grid on date on start up flag_equatorial_J2000_grid b
58. _display_no_texture bool 0 8 0 Set to true to suppress displaying of nebula textures flag_nebula_display_no_texture bool 0 8 0 Set to true to suppress displaying of nebula textures 50 APPENDIX A CONFIGURATION FILE continued Section ID Version Description flag_milky_way bool all Set to false to hide the Milky Way milky_way_intensity float 0 8 0 Sets the relative brightness with which the milky way is drawn Typical value 1to 10 max_mag_nebula_name float all Sets the magnitude of the nebulae whose name is shown Typical value 8 nebula_scale float 0 8 0 Sets how much to scale nebulae a setting of 1 will display nebulae at normal size flag_bright_nebulae bool all Set to true to increase nebulae brightness to enhance viewing less realistic flag_nebula_ngc bool 0 8 0 Enables disables display of all NGC objects Section Chart_color Section ID Version Description azimuthal_color float 0 8 0 Sets the colour of the azimuthal grid in RGB R G B values where is the maximum e g 1 0 1 0 1 0 for white gui_base_color float 0 8 0 These three numbers determine the colour of R G B the interface in RGB values where 1 is the maximum e g 1 0 1 0 1 0 for white const_text_color float 0 8 0 These three numbers determine the colour of R G B the text in RGB values where 1 is the maximum e g 1 0 1 0 1 0 for white equatorial_color float
59. a Factory Version 1 6 is a freebee that works well and can be downloaded from the internet a Google search will find it I used version 3 4 that is better and cost about 40 off the Internet This program has many options and can be configured to suit most cameras and can make a seamless 360 panorama in barrel form that will take a highly trained eye to find where the joins occur The resulting panorama was then loaded into The Gimp and trimmed to a suitable size Mine ended up14024 x 1601 pixels I trimmed the vertical size to 1024 by cutting back then stretched the 14024 to 14336 pixels almost no distortion that would allow cutting into 14 1024 x1024 pictures at a later date If the height of the panorama had been greater I could have made fewer pictures and so shown more of the foreground See figure E 1 If you have prominent foreground items like posts wires etc that occur in adjacent pictures the panorama program will have difficulty in discerning them because of the 3D effect and may give double images I overcame this by painting out the offending item by cut and paste between the two pictures Quite easy with a little practice using the zoom in facility and I found the MSpaint program the easiest to do this in Figure E 2 Processing the panorama to reduce ghosting Removing some of the ghosting from the panorama Before and after using copy and paste with MSpaint E 0 7 Removing the background to make it transparent This is the
60. ack to today core setDate now Return screen to original positiion so that we know the script is over LandscapeMgr setFlagLandscape True LandscapeMgr setFlagAtmosphere false LandscapeMgr setFlagFog false This script has been programmed to store the starting position and return at the end of the show LandscapeMegr xxx commands Note the format of each line and command the command first core clear with how the command will act with its options natural enclosed in brackets followed by a A comment line is preceded with G 0 13 Writing Your Own Scripts With a little practice most users of Stellarium shold be able to write scripts using the sim plified table of commands by modifying existing scripts or starting from scratch as your knowledge increases Look at the sample script in the previous section Table G 2 A table of common script commands collected from the sample scripts See table G 2 for a full list See table G 4 for a full list See table G 6 for a full list 84 APPENDIX G CREATING SCRIPTS FOR STELLARIUM Command Description ConstellationMgr setFlagIsolateSelect Boolean True or false ConstellationMgr setFlagLines Boolean True or false ConstellationMgr setFlagLabels Boolean True or false ConstellationMgr setFlagLabels Boolean True or false ConstellationMgr setFlagArt Boolean True or false ConstellationMgr setFlagBoun
61. agnitudes The zero point of the modern scale was originally defined as the brightness of the star Vega however this was re defined more formally in 1982 2 Objects brighter than Vega are given negative magnitudes The absolute magnitude of a star is defined as the magnitude a star would appear if it were 10 parsecs from the observer Table L2 lists several objects that may be seen in the sky their apparent magnitude and their absolute magnitude where applicable only stars have an absolute magnitude value The planets and the Moon don t give out light like a star does they reflect the light from the Sun 13 5 Luminosity Luminosity is an expression of the total energy radiated by a star It may be measured in watts however astronomers tend to use another expression solar luminosities where an object with twice the Sun s luminosity is considered to have two solar luminosities and so on Luminosity is related to absolute magnitude 14 Precession As the Earth orbits the Sun throughout the year the axis of rotation the line running through the rotational poles of the Earth seems to point towards the same position on the celestial sphere as can be seen in figure L4 The angle between the axis of rotation and the perpendicular of the orbital plane is called the obliquity of the ecliptic It is 23 27 Observed over very long periods of time the direction the axis of rotation points does actually change The angle between the
62. al and type stellarium Chapter 3 Interface Guide Figure 3 1 A composite screenshot showing Stellarium in both day time left and night time right 3 1 Tour At the bottom left of the screen you can see the status bar This shows the current observer location field of view FOV graphics performance in frames per second FPS and the current simulation date and time The rest of the view is devoted to rendering a realistic scene including a panoramic langscape and the sky If the simulation time and observer location are such that it is night time you will see stars planets and the moon in the sky all in the correct positions You can drag with the mouse on the sky to look around or use the cursor keys You can zoom with the mouse wheel or the page up page down keys 10 3 1 TOUR CHAPTER 3 INTERFACE GUIDE If you move the mouse over the status bar it will move up to reveal a tool bar which gives quick control over the program 3 1 1 Time Travel When Stellarium starts up it sets its clock to the same time and date as the system clock However Stellarium s clock is not fixed to same time and date as the system clock or indeed to the same speed We may tell Stellarium to change how fast time should pass and even make time go backwards So the first thing we shall do is to travel into the future Let s take a look at the time control buttons on the right hand ride of the tool bar table B 2 If you hover the mo
63. and Tycho Catalogues and 10 000 non stellar objects included to complement the catalogue data There were questions over whether Hipparcos has a systematic error of about milli arc second in at least some parts of the sky The value determined by Hipparcos for the distance to the Pleiades is about 10 less than the value obtained by some other methods By early 2004 the controversy remained unresolved Stellarium uses the Hipparcos Catalogue for star data as well as having traditional names for many of the brighter stars The stars tab of the search window allows for search ing based on a Hipparcos Catalogue number as well as traditional names e g the star Sadalmelik in the constellation of Aquarius can be found by searching for the name or it s Hipparcos number 109074 J 11 2 The Messier Objects The Messier objects are a set of astronomical objects catalogued by Charles Messier in his catalogue of Nebulae and Star Clusters first published in 1774 The original motivation behind the catalogue was that Messier was a comet hunter and was frustrated by objects which resembled but were not comets He therefore compiled a list of these objects The first edition covered 45 objects numbered M1 to M45 The total list consists of 110 objects ranging from M1 to M110 The final catalogue was published in 1781 and printed in the Connaissance des Temps in 1784 Many of these objects are still known by their Messier number Because the Messier li
64. ansparent is called Opaque Examples of suitable formats for Transparent copies include plain ASCII without markup Texinfo input format TeX input format SGML or XML using a publicly available DTD and standard conforming simple HTML PostScript or PDF designed for human modification Examples of transparent image formats include PNG XCF and JPG Opaque formats include proprietary formats that can be read and edited only by proprietary word processors SGML or XML for which the DTD and or processing tools are not generally available and the machine generated HTML PostScript or PDF produced by some word processors for output purposes only The Title Page means for a printed book the title page itself plus such following pages as are needed to hold legibly the material this License requires to appear in the title page For works in formats which do not have any title page as such Title Page means the text near the most prominent appearance of the work s title preceding the beginning of the body of the text A section Entitled XYZ means a named subunit of the Document whose title either is precisely XYZ or contains XYZ in parentheses following text that translates XYZ in another language Here XYZ stands for a specific section name mentioned 119 APPENDIX M GNU FREE DOCUMENTATION LICENSE below such as Acknowledgements Dedications Endorsements or History To Preserve the Title of such a section when you modify the Do
65. ars labels Alt S Miscellaneous Copy selected object Ctrl C information to clipboard Go to home Ctrl H Quit Ctrl Q Save screenshot Ctrl S Switch between equatorial and Ctrl M azimuthal mounts Toggle visibility of GUI Ctrl T Movement and Selection Centre on selected object object Space information to clipboard Set home planet to selected Ctrl G planet Track object T Zoom in on selected object Zoom out Angle Measure Angle measure Ctrl A Exoplanets Show exoplanets Ctrl Alt E Pulsars Show pulsars Ctrl Alt P Quasars Show Quasars Ctrl Alt Q Table 3 8 Table of key bindings 17 3 1 TOUR CHAPTER 3 INTERFACE GUIDE Table of key bindings Continue cordinates Oculars Ocular view Ctr1 O Ocular popup menu Alt O Select next eyepiece Ctrl PgUp Select next telescope Ctrl PgDown Select previous eyepiece Shift PgDown Show cross hairs Alt C Telerad sight Ctrl B Satellites Satellite hints Ctrl Z Satellite labels Shift Z Satellite configuration window Alt Z Telescope Control Move telescope 1 to selected Ctrl 1 object Move telescope 1 to point Alt 1 currently centre of the screen Move telescope 2 to selected Ctrl 2 object Move telescope 2 to point Alt 2 currently centre of the screen Move telescope 3 to selected Ctrl 3 object Move telescope 3 to point Alt 3 currently centre of the screen Move telescope 4 to sele
66. at are in common use J 2 4 1 Bayer Designation German astronomer Johan Bayer devised one such system in the 16 17th century His scheme names the stars according to the constellation in which they lie prefixed by a lower case Greek letter starting at for the brightest star in the constellation and proceeding with B y in descending order of apparent magnitude For example such a Bayer Designation for Sirius is Canis Majoris note that the genitive form of the constellation name is used There are some exceptions to the descending magnitude ordering and some multiple stars both real and optical are named with a numerical superscript after the Greek letter e g 7 T Orionis J 2 4 2 Flamsteed Designation English astronomer John Flamsteed numbered stars in each constellation in order of in creasing right ascension followed by the form of the constellation name for example 61 Cygni J 2 4 3 Catalogues As described in section T 11 various star catalogues assign numbers to stars which are often used in addition to other names Stellarium gets it s star data from the Hipparcos catalogue and as such stars in Stellarium are generally referred to with their Hipparcos number e g HP 62223 Figure J 2 shows the information Stellarium displays when a star is selected At the top the common name and Flamsteed designation are shown followed by the RA Dec coordinates apparent magnitude distance and Hippar
67. atch the movement of the stars we can see that they seem to rotate around a static point about once a day Stellarium is the perfect tool to demonstrate this 1 Open the configuration window select the location tab Set the location to be some where in mid Northern latitudes The United Kingdom is an ideal location for this demonstration 2 Turn off atmospheric rendering and ensure cardinal points are turned on This will keep the sky dark so the Sun doesn t prevent us from seeing the motion of the stars when it is above the horizon 3 Pan round to point North and make sure the field of view is about 90 4 Pan up so the N cardinal point on the horizon is at the bottom of the screen 5 Now increase the time rate Press k 1 1 1 1 this should set the time rate so the stars can be seen to rotate around a point in the sky about once every ten seconds If you watch Stellarium s clock you ll see this is the time it takes for one day to pass as this accelerated rate The point which the stars appear to move around is one of the Celestial Poles The apparent movement of the stars is due to the rotation of the Earth The location of the observer on the surface of the Earth affects how she perceives the motion of the stars To an observer standing at Earth s North Pole the stars all seem to rotate around the zenith the point directly upward As the observer moves South towards the equator the location of the celestial pole mo
68. axis of rotation and the orbital plane stays constant but the direction the axis points the position of the celestial pole transcribes a circle on the stars in the celestial sphere This process is called precession The motion is similar to the way in which a gyroscope slowly twists as figure 5jillustrates 97 L5 PARALLAX APPENDIX I ASTRONOMICAL CONCEPTS Figure 1 4 Obliquity of the Ecliptic Precession is a slow process The axis of rotation twists through a full 360 about once every 28 000 years Precession has some important implications 1 RA Dec coordinates change over time albeit slowly Measurements of the positions of stars recorded using RA Dec coordinates must also include a date for those co ordinates 2 Polaris the pole star won t stay a good indicator of the location of the Northern celestial pole In 14 000 years time Polaris will be nearly 47 away from the celestial pole I 5 Parallax Parallax is the change of angular position of two stationary points relative to each other as seen by an observer due to the motion of said observer Or more simply put it is the apparent shift of an object against a background due to a change in observer position This can be demonstrated by holding ones thumb up at arm s length Closing one eye note the position of the thumb against the background After swapping which eye is open without moving the thumb appears to be in a different position against the backgrou
69. ay invisible M31 and M44 may be glimpsed with the naked eye but are very indistinct clouds are brightly lit even in moderate sized telescopes the brightest Messier objects are only ghosts of their true selves City sky white 4 5 at best Sky glows white or orange you can easily read M31 and M44 are barely glimpsed by an experienced observer on good nights even with telescope only bright Messier objects can be detected stars forming familiar constellation patterns may be weak or completely invisible Inner City sky white 4 0 at best Sky is brilliantly lit with many stars forming constellations invisible and many weaker constellations invisible aside from Pleiades no Messier object is visible to the naked eye only objects to provide fairly pleasant views are the Moon the Planets and a few of the brightest star clusters Table 5 4 Bortle Dark Sky Scale from Wikipedia 32 5 7 CUSTOMISING LANDSCAPES CHAPTER 5 ADVANCED USE 5 7 Customising Landscapes It is possible to create your own landscapes for Stellarium There are three types of land scape Single Fish eye Method Using a fish eye panorama image Single Spherical Method Using a spherical panorama image Multiple Image Method also called old style landscapes Using a series of images split from a 360 strip panorama image a ground image Each landscape has it s own sub directory in lt user director
70. bels in RGB values R G B where 1 is the maximum e g 1 0 1 0 1 0 for white star_circle_color float 0 8 0 Sets the colour of the circle of the star labels in R G B RGB values where is the maximum e g 1 0 1 0 1 0 for white cardinal_color float 0 8 0 Sets the colour of the cardinal points in RGB R G B values where is the maximum e g 1 0 1 0 1 0 for white planet_names_color float 0 8 0 Sets the colour of the planet names in RGB R G B values where is the maximum e g 1 0 1 0 1 0 for white planet_orbits_color float 0 8 0 Sets the colour of the orbits in RGB values R G B where is the maximum e g 1 0 1 0 1 0 for white object_trails_color float 0 8 0 Sets the colour of the planet trails in RGB R G B values where is the maximum e g 1 0 1 0 1 0 for white chart_color float 0 8 0 Sets the colour of the chart in RGB values R G B where 1 is the maximum e g 1 0 1 0 1 0 for white telescope_circle_color float 0 8 0 Sets the colour of the telescope location R G B indicator RGB values where 1 is the maximum e g 1 0 1 0 1 0 for white telescope_label_color float 0 8 0 Sets the colour of the telescope location label R G B RGB values where is the maximum e g 1 0 1 0 1 0 for white Section color and night colo D Section L Version Description default_color float 0 9 0 Sets the default colour in RGB values R G B where 1 is the maximum e g 1 0 1 0 1 0 for white Description az
71. c second 96 Mimas minor planets minutes of arc 96 Moon 13 651 97 108 moon multiple star systems 101 nadir naked eye 114 navigation nebula nebulae Neptune obliquity of the ecliptic 97 observer observer location OpenGL 8 optical doubles optical multiples orbit orbital plane 97 panorama alone Tae 98 111 parsec INDEX INDEX perspective projection hints Jupiter Mars Mercury 107 Neptune Pluto Saturn 107 Uranus 107 Venus 107 planet trails planetarium 6 planetary bodies planetary nebulae 37 109 planetoids 108 PNG Pogson Norman 97 pole celestial 92 94 98 Earth pole star 98 precession Precision projection mode 25 fisheye perspective stereographic proper mano i proper name quit RA RA Dec 103 right ascension 94 98 Russell Henry Norris satellite 106 Saturn screenshot save directory script save directory scripts seconds of arc 96 shooting stars side tool ee sidereal day 66 sky culture 66 sky cultures sky time 66 Sol 107 solar day 96 126 solar system 37 Solar System body 66 spectra 104 spectral type speed of light spherical 33 spiral galaxies 109 star 66 dog star the 103 Sirius 103 star catalogue 69 star eet star clusters 111 star data records 69 Stars 108 stars 20
72. cos number J 2 5 Spectral Type amp Luminosity Class Stars have many different colours Seen with the naked eye most appear to be white but this is due to the response of the eye at low light levels the eye is not sensitive to colour Typically the unaided eye can start to see differences in colour only for stars that have apparent magnitude brighter than 1 Betelgeuse for example has a distinctly red tinge to it and Sirius appears to be 103 J 2 STARS APPENDIX J ASTRONOMICAL PHENOMENA blue By splitting the light from a star using a prism attached to a telescope and measuring the relative intensities of the colours of light the star emits the spectra a great deal of interesting information can be discovered about a star including its surface temperature and the presence of various elements in its atmosphere Spectral Type Surface Temperature K Star Colour O 28 000 50 000 Blue B 10 000 28 000 Blue white A 7 500 10 000 White blue F 6 000 7 500 Yellow white G 4 900 6 000 Yellow K 3 500 4 900 Orange M 2 000 3 500 Red Table J 2 Spectral Types Astronomers groups stars with similar spectra into spectral types denoted by one of the following letters O B A F G K and Type O stars have a high surface temperature up to around 50 000 K while the at other end of the scale the M stars are red and have a much cooler surface temperature typically 3000 K T
73. cted Ctrl 4 object Move telescope 4 to point Alt 4 currently centre of the screen Move telescope 5 to selected Ctrl 5 object Move telescope 5 to point Alt 5 currently centre of the screen Move telescope 6 to selected Ctrl 6 object Move telescope 6 to point Alt 6 currently centre of the screen Move telescope 7 to selected Ctrl 7 object Move telescope 7 to point Alt 7 currently centre of the screen Move telescope 8 to selected Ctrl 8 object Move telescope 8 to point Alt 8 currently centre of the screen Move telescope 9 to selected Ctrl 9 object Move telescope 9 to point Alt 9 currently centre of the screen Move telescope to a given set of Ctrl 0 Table 3 9 Table of key bindings 18 3 1 TOUR CHAPTER 3 INTERFACE GUIDE Table of key bindings Continue window Scripts Run landscape script from file Ctrl U 2 Show and zoom moon Ctrl U 1 Toggle script recording Not in Ctrl R use Pause script recording Not in 6 use Windows Configuration window F2 date time window FS Help window Fl Location window F6 Script console window F12 Search window F3 Short cuts window F7 Sky and viewing options F4 Table 3 10 Table of key bindings This is a table of all the current key bindings used by Stellarium If these keys clash with other programs they can be edited by pressing the edit keyboard shortcuts tab 19 Chapter 4 Configuration Most of Stel
74. ction titles in the list of Invariant Sections in the license notice of the combined work In the combination you must combine any sections Entitled History in the various original documents forming one section Entitled History likewise combine any sections Entitled Acknowledgements and any sections Entitled Dedications You must delete all sections Entitled Endorsements 6 COLLECTIONS OF DOCUMENTS You may make a collection consisting of the Document and other documents released under this License and replace the individual copies of this License in the various documents with a single copy that is included in the collection provided that you follow the tules of this License for verbatim copying of each of the documents in all other respects You may extract a single document from such a collection and distribute it individually under this License provided you insert a copy of this License into the extracted document and follow this License in all other respects regarding verbatim copying of that document 7 AGGREGATION WITH INDEPENDENT WORKS A compilation of the Document or its derivatives with other separate and independent documents or works in or on a volume of a storage or distribution medium is called an aggregate if the copyright resulting from the compilation is not used to limit the legal rights of the compilation s users beyond what the individual works permit When the Document is included in an aggregate this Lice
75. cument means that it remains a section Entitled XYZ according to this definition The Document may include Warranty Disclaimers next to the notice which states that this License applies to the Document These Warranty Disclaimers are considered to be included by reference in this License but only as regards disclaiming warranties any other implication that these Warranty Disclaimers may have is void and has no effect on the meaning of this License 2 VERBATIM COPYING You may copy and distribute the Document in any medium either commercially or noncommercially provided that this License the copyright notices and the license notice saying this License applies to the Document are reproduced in all copies and that you add no other conditions whatsoever to those of this License You may not use technical measures to obstruct or control the reading or further copying of the copies you make or distribute However you may accept compensation in exchange for copies If you distribute a large enough number of copies you must also follow the conditions in section 3 You may also lend copies under the same conditions stated above and you may publicly display copies 3 COPYING IN QUANTITY If you publish printed copies or copies in media that commonly have printed covers of the Document numbering more than 100 and the Document s license notice requires Cover Texts you must enclose the copies in covers that carry clearly and legibly all these Cov
76. d stars and draws how the sky would look to an observer depending on their location and the time It can also draw the constellations and simulate astronomical phenomena such as meteor showers and solar or lunar eclipses It can also display how the sky will look from any other position in our solar system Stellarium may be used as an educational tool for teaching about the night sky as an observational aid for amateur astronomers wishing to plan a night s observing or simply as a curiosity it s fun Because of the high quality of the graphics that Stellarium produces it is used in some real planetarium projector products Some amateur astronomy groups use it to create sky maps for describing regions of the sky in articles for newsletters and magazines The development of a powerful scripting system has been continuing for a number of years now and can now be called operational The use of a script was recognised as a perfect way of arranging a display of a sequence of astronomical events from the earliest versions of Stellarium and a simple system called the Stratoscript was implemented The scipting facility is Stellarium s version of a Presentation a feature that may be used to run an astronomical or other presentation for instruction or entertainment from within the Stellarium program The original Stratoscript was quite limited in what it could do so a new Stellarium Scripting System has been developed Stellarium is under
77. daries Boolean True or false ConstellationMgr setArtIntensity x 6699 x is a value between 0 and 1 core clear x A delay between operations where x is a time in seconds natural starchart deepspace core debug setting sky culture id core dropvideo tag core getAllSkyCultureIDs core getSkyCultureName core getDate core getJDay core getObjectPosition Object core getScreenHeight core getScreenWidth core goHome core loadSkyImage image name RA Dec Center Angle brightness rotation Minimum resolution boolean Tag a variable name for file RA HHh MMm SSs Dec sDDd MMm SSs Centre Angular size max brightness rotation Min res 0 5 bool true or false wow core loadVideo name 0 5 tag h pos v pos bool Load a video file where Name file name tag suitable variable name h pos horizontal position in pixels from left of screen v pos vertical position in pixels from top of screen bool True or false core moveToaltAzi alt azm x core moveToRADec RA Dec Set the display view RA dec values in HHh MMm SSs and SDDd MMm SSs Table G 2 Table of scripting Commands 85 APPENDIX G CREATING SCRIPTS FOR STELLARIUM Command Description core selectObjectB yName obj
78. ded at compile time However it is far more practical if these scripts are re written in the sss format e The ability to automatically store a sequence of events from a Stellarium session as a script for later play back e The implementation of a DSS background This was actually included in a test branch and the code is still present It was shown to be practical in a Stellarium derivative called Virgo However this requires a repository for the immense data base and it has so far been beyond the resources of stellarium l Version 0 10 1 introduced a replacement scripting engine with many features not found in the Stratoscript engine As of version 0 12 x this is still in development but is finished to all extents and purposes However new commands may be added from time to time Eventually a compatibility layer may be implemented which should allow on the fly translation of Stratoscript to the new engine but this is not implemented yet 7 Chapter 2 Installation 2 1 System Requirements e Linux Unix Windows 2000 NT XP Vista Windows 7 8 MacOS X 10 3 x or greater e A 3D graphics card with a support for OpenGL e A dark room for realistic rendering details like the Milky Way or star twinkling can t be seen in a bright room e Minimum of 256 MiB RAM 1 GiB or more required for the largest star catalogues Note The latest version of Stellarium to work on Windows 98 2e is 0 8 2 2 2 Downloading You should visit t
79. doubles and optical multiples J 2 3 Constellations The constellations are groupings of stars that are visually close to one another in the sky The actual groupings are fairly arbitrary different cultures have group stars together into different constellations In many cultures the various constellations have been associated with mythological entities As such people have often projected pictures into the skies as can be seen in figure J 1 which shows the constellation of Ursa Major On the left is a picture with the image of the mythical Great Bear on the right only a line art version is shown The seven bright stars of Ursa Major are widely recognised known variously as the plough the pan handle and the big dipper This sub grouping is known as an asterism a distinct grouping of stars On the right the picture of the bear has been removed and only a constellation diagram remains Stellarium can draw both constellation diagrams and artistic representations of the constellations Multiple sky cultures are supported Western Polynesian Egyptian and Chinese constellations are available although at time of writing the non Western con stellations are not complete and as yet there are no artistic representations of these sky cultures Aside from historical and mythological value to the modern astronomer the constella tions provide a way to segment the sky for the purposes of describing locations of objects indeed
80. e brightness of the constellation art images Typical value 0 5 constellation_art_fade_duration float all Sets the amount of time the constellation art takes to fade in or out in seconds Typical value 1 5 flag_chart bool 0 8 0 Enable chart mode on startup flag_night bool all Enable night mode on startup light_pollution_luminance float 0 9 0 Sets the level of the light pollution simulation use_luminance_adaptation bool 0 9 0 Enable dynamic eye adaptation flag_render_solar_shadows bool 0 12 0 Enable render of the solar shadows 64 Appendix B Precision Stellarium uses the VSOP87 method to calculate the variation in position of the planets over time As with other methods the precision of the calculations vary according to the planet and the time for which one makes the calculation Reasons for these inaccuracies include the fact that the motion of the planet isn t as predictable as Newtonian mechanics would have us believe As far as Stellarium is concerned the user should bear in mind the following properties of the VSOP87 method Precision values here are positional as observed from Earth Object s Method Notes Mercury Venus VSOP87 Precision is 1 arc second from 2000 B C 6000 A D Earth Moon barycenter Mars Jupiter Saturn VSOP87 Precision is 1 arc second from O A D 4000 A D Uranus Neptune VSOP87 Precision is 1 arc second from 4000 B C 8000 A D Pluto 2 Pluto s posi
81. e Sun 3651 solar days The length of a sidereal day is about 23 hours 56 minutes and 4 seconds It takes exactly one sidereal day for the celestial sphere to make one revolution in the sky Astronomers find sidereal time useful when observing When visiting observatories look out for doctored alarm clocks that have been set to run in sidereal time 13 3 Angles Astronomers typically use degrees to measure angles Since many observations require very precise measurement the degree is subdivided into sixty minutes of arc also known as arc minutes Each minute of arc is further subdivided into sixty seconds of arc or arc seconds Thus one degree is equal to 3600 seconds of arc Finer grades of precision are usually expressed using the SI prefixes with arc seconds e g milli arc seconds one milli arc second is one thousandth of an arc second 1 3 3 1 Notation Degrees are denoted using the symbol after a number Minutes of arc are denoted with a and seconds of arc are denoted using Angles are frequently given in two formats 1 DMS format degrees minutes and seconds For example 90 5 2 When more precision is required the seconds component may include a decimal part for ex ample 90 5 2 432 2 Decimal degrees for example 90 2533 1 3 4 The Magnitude Scale When astronomers talk about magnitude they are referring to the brightness of an object How bright an object appears to be depends on how much l
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84. e stars_1_0v0_3 cat stars_2_0v0_3 cat e stars_3_0v0_2 cat e stars_4 _1v0_0 cat 69 D 2 STAR CATALOGUE FILE FORMAT APPENDIX D STAR CATALOGUE e stars_5_1v0_0 cat e stars_6_2v0_0 cat e stars_7_2v0_0 cat e stars_8 2v0_0 cat There also exist some control and reference files e stars_hip_cids_0v0_0 cat e stars_hip_sp_0v0_0 cat e gvs_hip_part dat e stars ini e name fab When Stellarium starts it reads the stars ini file from which it determines the names of the other files which it then loads The stars_hip_cids_0v0_0 catandstars_hip_sp_0v0_0 cat files con tain reference data for the main catalogue files A given catalogue file models stars for one and only one level i e for a fixed number of zones which is recorded in the header of the file Individual star records do not contain full positional coordinates instead they contain coordinates relative to the central position of the zone they occupy Thus when parsing star catalogues 1t is necessary to know about the zone model to be able to extract positional data File Data ml Data Record Geodesic Records Notes Size Level stars_0_0v0_3 cat O 28 bytes 0 5 013 Hipparcos stars_1_0v0_3 cat O 28 bytes 1 21 999 Hipparcos stars_2_0v0_3 cat O 28 bytes 2 151 516 Hipparcos stars_3_1v0_2 cat 1 10 bytes 3 434 064 Tycho stars 4 1v0_O cat 1 10 bytes 4 1 725 497 Tycho stars_5_2v0_0 cat 2 8 bytes 5 7 669 01
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86. ect boolean Selects an object to display true or false core setDate year month day T Hour Min sec Sets the date time for the event start Variables d local d yyyy mm dd T hh mm ss local will get current time now current Date time core setGuiVisible Boolean True or false core setMinFps x Prevents a jerky display by increasing the minimum frame rate x fps in secondsTrue or false core setObserverLocation lon Lat off x town country Set the location for display lon Lat off X town country core setSkyCulture id core setTimeRate x Sets the time step rate for the display x time in seconds GridLinesMgr setFlagEquatorialGrid Boolean True or false GridLinesMgr setFlagAzimuthalGrid Boolean True or false GridLinesMgr setFlagEclipticLine Boolean True or false GridLinesMgr setFlagEquatorLine Boolean True or false GridLinesMgr setFlagMeridianLine Boolean True or false LabelMgr deleteLabel id Id is the preset string LabelMgr deleteAllLabels Deletes all labels LabelMgr labelScreen tag h pos v pos boolean 25 color LabelMgr setLabelShow d Boolean Id is a preset string true or false LandscapeMgr getCurrentLandscapeName Landscape name LandscapeMgr setFlag Atmosphere Boolean True or false LandscapeMg
87. ectory By default this is C Program Files Stellarium although this can be adjusted during the installation process user directory This is the Stellarium sub folder in the Application Data folder for the user account which is used to run Stellarium Depending on the version of Windows and its configuration this could be any of the following each of these is tried if it fails the next in the list if tried SAPPLICATION DATA Stellarium SAPPDATA Roaming Stellarium SUSERPROFILE Stellarium SHOMEDRIVES SHOMEPATH S Stellarium HOMESAStellariuml Stellarium s installation directory al Thus on a typical Windows XP system with user Bob Dobbs the user directory will be C Documents and Settings Bob Dobbs Application Data Stellarium The installation directory was referred to as the config root directory in previous versions of this guide 27 5 1 FILES AND DIRECTORIES CHAPTER 5 ADVANCED USE Or on a typical Windows Vista Windows 7 amp 8 system with user Bob Dobbs the user directory will be C Users Bob Dobbs Appdata Roaming Stellarium Note Appdata and Application Data are normally a hidden file Stellarium version 0 9 0 did use the 3APPDATA Stellarium folder Thusifaconfig ini file exists in the SUSERPROFILE Stellarium directory that will be used in pref erence to the SAPPDATA Stellarium directory This is to prevent users of version 0 9 0 from losing their s
88. ed on tour computer The Plugins tat 4 5 Plug ins need to be enabled at start up to be available as shown on the bar This allows for the selection of the plugins that you wish to be enabled at this time 23 4 5 THE VIEW SETTINGS WINDOW CHAPTER 4 CONFIGURATION 4 5 The View Settings Window The View settings window controls many display features of Stellarium which are not avail able via the main tool bar 4 5 1 Sky Tab Figure 4 6 The Sky tab of the View window The Sky tab of the View window4 6 contains settings for changing the general appear ane of the main sky view Some hightlights Absolute scale is the size of stars as rendered by Stellarium If you increase this value all stars will appear larger than before Relative scale determines the difference in size of bright stars compared to faint stars Values higher than 1 00 will make the brightest stars appear much larger than they do in the sky This is useful for creating star charts or when learning the basic constellations Twinkle controls how much the stars twinkle Dynamic eye adaptation When enabled this feature reduces the brightness of faint objects when a bright object is in the field of view This simulates how the eye can be dazzled by a bright object such as the moon making it harder to see faint stars and galaxies Light pollution In urban and suburban areas the sky is brightned by terrestrial light pollu tion reflected in the atmophere Stella
89. emove the sky and convert into an alpha layer texture Figure E 7 Fisheye Panorama The sample supplied with Stellarium is called Trees The horizon needs to be identified in the picture and the picture sized so that picture horizon is at O degrees altitude This will occur if the panorama above this horizon is sited to be about 80 of the total extent of the texture and the balance of the border filled with a dark colour right up to the horizon This will make the horizon in your landscape at 0 degrees Note the Trees landscape puts the horizon at about 20 degrees altitude It is possible to make a synthetic fisheye texture using the same method as making a ground from a spherical panorama but it is hardly worth the trouble as even a simple 2048 x 1024 pixel sperical will give a far better result 80 Appendix F Creating New Sky Cultures In Stellarium by Barry Gerdes and the Stellarium team 2013 08 19 Although this procedure is based on the Microsoft Windows System the basics will apply to any platform that can run the programs mentioned or similar programs on the preferred system A most important part of Stellarium has been the ability to run personal representa tions of astronomical phenomena using the display power of Stellarium The sky culture section folder skycultures can have new additions added at any time like the landscapes scripts nebula textures etc as long as the format follows the requirements as described i
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91. er at the beginning of the record indicates that the record is a comment and will be ignored by Stel larium Each record is TAB separated with the following fields 1 Location name province state 2 Country ISO Code Full English Name 3 Type code C B Capital R Regional capital N Normal city O Observatory L Lander Population in thousands Latitude decimal degrees N S Longitude decimal degrees E W Altitude in meters Light pollution level 0 9 Bortle scale value Noa NAMBA Timezone emtpy means automatic 10 Planet empty means Earth 11 Landscape ID the ID for a landscape to be used with thiis location or empty means use default data user_locations txt The same format as base_locations txt This file is added to when auser defines a new location and is usu ally found in the user data directory area rather than the installation area data constellations_boundaries dat This file provides data necessary for Stellarium to draw the boundaries of he constellations stars x name fab This file defines the Flamsteed designation for a star see section T 2 4 2 Each line of the file contains one record of two fields separated by the pipe character The first field is the Hipparcos catalogue number of the star the second is the Flamsteed designation e g 72370 Q_Aps data zone tab Time zone information Table 5 11 Configuration files 5 12 Taking
92. erage density which is much less than the terrestrial planets Saturn s mean density is only about 0 7 g cm it would float in water 4OK it s a silly thing to say gas giants really aren t something you can take down the local swimming pool and throw in the deep end It s a nice thought though 107 J 5 THE MINOR PLANETS APPENDIX J ASTRONOMICAL PHENOMENA Planets Figure J 4 Planets and dwarf planets in our solar system The planet sizes are drawn to scale but not their distances from the Sun or one another J 5 The Minor Planets As well as the Major Planets the solar system also contains innumerable smaller bodies in orbit around the Sun These are generally classed as the minor planets or planetoids and include asteroids and sometimes comets J 5 1 Asteroids Asteroids are celestial bodies orbiting the Sun in more or less regular orbits mostly between Mars and Jupiter They are generally rocky bodies like the inner terrestrial planets but of much smaller size There are countless in number ranging in size from about ten meters to thousands of kilometres J 5 2 Comets A comet is a small body in the solar system that orbits the Sun and at least occasionally exhibits a coma or atmosphere and or a tail Comets have a very eccentric orbit very elliptical and as such spend most of their time a very long way from the Sun Comets are composed of rock dust and ices When they come close
93. es the stars visible in the daytime Nebulae amp Galaxies n Toggles marking the positions of Nebulae and Galaxies when the FOV is too wide Planet Hints e p Toggles planet position indicators Coordinate System Enter Toggles Alt Azi amp RA Dec coordinates wr Goto 7s Space Centres the view on the selected object Nebula displays a none Toggles the nebulae textures on or off Night Mode none Toggle night mode which changes the col oring of some display elements Full Screen Mode om F11 Toggle full screen mode e gt Flip image horizontal CTRL SHIFT h Flips the image in the horizontal plane Note this button is not enable by default amp Flip image vertical z CTRL SHIFT v Flips the image in the vertical plane Note this button is not enable by default Quit Stellarium x CTRL Q Close Stellarium Note Keyboard shortcut is COMMAND Q on OSX machines Help Window E F1 Show the help window which lists key bind ings and other useful information Configuration Window F2 Show the configuration window F Search Window 1 F3 or CTRL f Show the the object search window View Window F4 Show the view window Time Window O FS Show the display of the help window a 4 Location Window g F6 Show the observer location window map Table 3 6 Main tool bar buttons 14 3 1 TOUR CHAPTER 3 INTERFACE GUIDE 3 1 6 The Object Search Window Figure 3 5 The search window object and position
94. et a white screen With this problem I used the following procedure to make the spherical into a four panel multi panel landscape with a very effective ground that matched well E 0 9 Converting a Spherical Panorama into a Multi Panel Most computers with standard video cards will not display spherical panoramas larger than 4096 x 2048 and some will not even go beyond 2048 x 1024 This makes rather poor resolution panaoramas OK for planets but not very pretty for your local environment If the panorama can have a horizontal section cut out that can keep the detail within a 1024 vertical boundary it is ideal for processing into 1024 x 1024 sections If the original is 8192 x4096 you will be able to make 8 panels at 1024 x 1024 Figure E 4 Spherical Panorama 4 1 I made the English Garden into a 4096 x 1024 quite easily because there was a lot of blank space above the horizon This would allow 4 panels 1024 x 1024 pixels in fact if I 78 APPENDIX E CREATING A PERSONALISED LANDSCAPE FOR STELLARIUM had a 8192 x 4096 version of the panorama I could have made it into 8 1024 x 1024 panels This would have given me quite a high resolution horizon Figure E 5 Sphrerical Panorama 8 1 When you have the sections proceed as with the previous description 1 Load the sections into TheGimp and process them into 1024 x 1024 textures with alpha layers as before 2 Next make a reduced size version of the panorama texture to a 2048 x 1024 ve
95. et to true if you want auto hide the horizontal toolbar auto_hide_vertical_toolbar bool 0 10 1 Set to true if you want auto hide the vertical toolbar day_key_mode string 0 9 1 Specifies the amount of time which is added and subtracted when the and keys are pressed calendar days or sidereal days This option only makes sense for Digitalis planetariums Values calendar or sidereal flag menu bool 0 6 2 0 10 0 flag_help bool 0 6 2 0 10 0 flag_infos bool 0 6 2 0 10 0 flag_show_topbar bool 0 6 2 0 10 0 continued 56 APPENDIX A CONFIGURATION FILE Section ID Version Description flag_show_time bool 0 6 2 0 10 0 flag_show_date bool 0 6 2 0 10 0 flag_show_appname bool 0 6 2 0 10 0 flag_show_selected_object_info bool 0 6 2 0 10 0 gui_base_color float 0 6 2 R G B 0 10 0 gui_text_color float 0 6 2 R G B 0 10 0 Section init_location Section ID Version Description name string 0 6 2 Sets your location s name This is an 0 10 0 arbitrary string For example Paris latitude DMS 0 6 2 Sets the latitude coordinate of the 0 9 1 observer Value is in degrees minutes seconds Positive degree values mean North negative South e g 55d14 30 00 longitude DMS 0 6 2 Sets the longitude coordinate of the 0 9 1 observer Value is in degrees minutes seconds Positive degree values mean East negative West e g 01d37 6 00 al
96. ettings when they upgrade screenshot save directory Screenshots were once saved to the Desktop although this can be changed with a command line option see section 5 3 They are now directed to user area eg Bob Dodds pictures In the earlier Windows version this was in the Documents and Settings area which is not accessible in Windows vista or 7 8 In these versions the User area is Users Also the latest versions of Windows 7 8 may not allow saving to existing user area without administrator permission This access can be set to allow by editing the permissions table as an adminstrator If you can t find the snapshots look in your config ini file main screenshot_dir C Users Bob Dobbs Pictures An alternate method that can be used for screen shots is to use Ctrl Print Screen This will take a snapshot that can be inserted as a new image into a graphics 5 1 2 MacOS X installation directory This is found inside the application bundle Stellarium app See the Inside Application Bundles for more information user directory This is the Library Preferences Stellarium sub directory of the users home directory screenshot save directory Screenshots are saved to the users Desktop 5 1 3 Linux installation directory This is in the share stellarium sub directory of the installa tion prefix i e usually usr share stellariumor usr local share stellarium user directory This is the stellarium sub directory of
97. f the moon There are three types of solar eclipses Partial The Moon only covers part of the Sun s surface Total The Moon completely obscures the Sun s surface Annular The Moon is at aphelion furthest from Earth in its elliptic orbit and its disc is too small to completely cover the Sun In this case most of the Sun s disc is obscured all except a thin ring around the edge J 10 2 Lunar Eclipses Lunar eclipses occur when the Earth moves between the Sun and the Moon and the Moon is in the Earth s shadow They occur under the same basic conditions as the solar eclipse but can occur more often because the Earth s shadow is so much larger than the Moon s Total lunar eclipses are more noticeable than partial eclipses because the Moon moves fully into the Earth s shadow and there is very noticeable darkening However the Earth s atmosphere refracts light bends it in such a way that some sunlight can still fall on the Moon s surface even during total eclipses In this case there is often a marked reddening of the light as it passes through the atmosphere and this can make the Moon appear a deep red colour J 11 Catalogues Astronomers have made various catalogues of objects in the heavens Stellarium makes use of several well known astronomical catalogues 110 J 11 CATALOGUES APPENDIX J ASTRONOMICAL PHENOMENA J 11 1 Hipparcos Hipparcos for High Precision Parallax Collecting Satellite was an astrometry
98. fairly rapid development and by the time you read this guide a newer version may have been released with even more features than those documented here Much of the newer development is in the Plug Ins section which is adding many new features that do not require core modification There are also many changes to the display as OpenGl is improved This will often require screen driver updates in your operating system to display new features effectively Check for updates to Stellarium at the Stellarium website If you have questions and or comments about this guide please email the author For comments about Stellarium itself visit the Stellarium forums Notes for version 0 12 x This document described release version 0 12 x of Stellarium The 0 12 x series bring a lot of significant changes to the project in both the underlying structure of the program code and in the outward appearance The most obvious change from the 0 9 x series of releases 1s the new user interface CHAPTER 1 INTRODUCTION Because of the scale of the changes in this release a few key features of older releases are not included as they are still waiting for a new implementation consistent with the changed structure of the program e Specifically the ability to run the older Stratoscripts This feature is not truly prac tical with the new structure although some of the scripts files with the subscript sts can still be run if the Stratoscript read feature is ad
99. far away that they are very dim and cannot be seen without large telescopes but there are dozens of galaxies which may be observed in medium to large sized amateur instruments Stellarium includes images of many galax ies including the Andromeda galaxy M31 the Pinwheel Galaxy M101 the Sombrero Galaxy M104 and many others Astronomers classify galaxies according to their appearance Some classifications in clude spiral galaxies elliptical galaxies lenticular galaxies and irregular galaxies J 7 The Milky Way It s a little hard to work out what our galaxy would look like from far away because when we look up at the night sky we are seeing it from the inside All the stars we can see are part of the Milky Way and we can see them in every direction However there is some structure There is a higher density of stars in particular places There is a band of very dense stars running right round the sky in huge irregular stripe Most of these stars are very dim but the overall effect is that on very dark clear nights we can see a large beautiful area of diffuse light in the sky It is this for which we name our galaxy The reason for this effect is that our galaxy is somewhat like a disc and we are off to one side Thus when we look towards the centre of the disc we see more a great concentration of stars there are more star in that direction As we look out away from the centre of the disc we see fewer stars we are staring out
100. fields Note This file is now compressed and no longer editable in a text editor However if you are connected to the internet it can be overriddien by the simbad data 5 8 2 Modifying ngc2000names dat Each line in the ngc2000names dat file contains one record A record relates an ex tended object catalogue number from ngc2000 dat with a name A single catalogue number may have more than one record in this file The record structure is as follows Offset Length Type Description 0 35 35s Name Note that messier numbers should be M then three spaces then the number 37 1 Joc 37 5 8 ADDING NEBULAE IMAGES CHAPTER 5 ADVANCED USE 38 d Catalogue number 44 30 s If an object has more than one record in the ngc2000names dat file the last record in the file will be used for the nebula label 5 8 3 Modifying textures json This file is used to describe each nebula image The file structure follows the JSON format a detailed description of which may be found at www json org The textures json file which ships with Stellarium has the following structure serverCredits optional a structure containing the following key value pairs short a short identifier of a server where the json file is found e g ESO full a longer description of a server e g ESO Online Digitised Sky Survey Server infoURL a URL pointing at a page
101. ge the rounded corners are not used The image file should be saved in PNG format with alpha transparency Wherever the image is transparent is where Stellarium will render the sky The landscape ini file for a fish eye type landscape looks like this this example 1f for the Trees landscape which comes with Stellarium landscape name Trees type fisheye maptex trees_512 png texturefov 210 Where name is what appears in the landscape tab of the configuration window type identifies the method used for this landscape fisheye in this case maptex is the name of the image file for this landscape texturefov is the field of view that the image covers in degrees 33 5 7 CUSTOMISING LANDSCAPES CHAPTER 5 ADVANCED USE 5 7 2 Single Panorama Method This method uses a more usual type of panorama the kind which is produced directly from software such as autostitich The panorama file should be copied into the lt config root gt landscapes lt landscape_id gt directory and a landscape ini file cre ated The Moon landscape which comes with Stellarium provides a good example of the contents of a landscape ini file for a spherical type landscape landscape name Moon type spherical maptex apollol7 png Where name is what appears in the landscape tab of the configuration window type identifies the method used for this landscape spherical in this case maptex is the name of the image file f
102. hand About 18 Using you hand in this way is not very precise but it s close enough to give you some way to translate an idea like Mars will be 45 above the Southeastern horizon at 21 30 Of course there is variation from person to person but the variation is compensated for somewhat by the fact that people with long arms tend to have larger hands In exercise L 2 you will work out your own handy angles 113 Appendix K Sky Guide This section lists some astronomical objects that can be located using Stellarium All of them can be seen with the naked eye or binoculars Since many astronomical objects have more than one name often having a proper name a common name and various cata logue numbers the table lists the name as it appears in Stellarium use this name when using Stellarium s search function and any other commonly used names The Location Guide column gives brief instructions for finding each object using nearby bright stars or groups of stars when looking at the real sky a little time spent learning the major constellations visible from your latitude will pay dividends when it comes to locating fainter and more interesting objects When trying to locate these objects in the night sky keep in mind that Stellarium displays many stars that are too faint to be visible without optical aid and even bright stars can be dimmed by poor atmospheric conditions and light pollution
103. he Stellarium website Download packages for various platforms are available directly from the main page Choose the correct package for your operating systent 2 3 Installation 2 3 1 Windows 1 Double click on the stellarium 0 12 2 exe file to run the installer 2 Follow the on screen instructions 2 3 2 MacOS X 1 Locate the stellarium 0 12 2 dmg file in finder and double click on it or open it using the disk copy program 2 Have a browse of the readme file and drag Stellariumto the Applications folder or somewhere else if you prefer 3 Note that it is better to copy Stellarium out of the dmg file to run it some users have reported problems when running directly from the dmg file Linux users your distribution may already carry Stellarium as part of the distro just look in your package manager 2 4 RUNNING STELLARIUM CHAPTER 2 INSTALLATION 2 3 3 Linux Check if your distribution has a package for Stellarium already if so you re probably best off using it If not you can download and build the source See the wiki for detailed instructions 2 4 Running Stellarium Windows The Stellarium installer creates an item in the Start Menu under in Programs section Select this to run Stellarium MacOS X Double click on Stellarium wherever you put it Linux If your distribution had a package you 1l probably already have an item in the Gnome or KDE application menus If not just use a open a termin
104. he Sun is a type G star with a surface temperature of around 5 500 K Spectral types may be further sub divided using a numerical suffixes ranging from 0 9 where 0 is the hottest and 9 is the coolest Table J 2 shows the details of the various spectral types For about 90 of stars the absolute magnitude increases as the spectral type tends to the O hot end of the scale Thus the whiter hotter stars tend to have a greater luminosity These stars are called main sequence stars There are however a number of stars that have spectral type at the M end of the scale and yet they have a high absolute magnitude These stars have a very large size and consequently are known as giants the largest of these known as super giants There are also stars whose absolute magnitude is very low regardless of the spectral class These are known as dwarf stars among them white dwarfs and brown dwarfs A luminosity class is an indication of the type of star whether it is main sequence a giant or a dwarf Luminosity classes are denoted by a number in roman numerals as described in table Luminosity class Description Ta Ib Super giants II Bright giants Il Normal giants IV Sub giants V Main sequence VI Sub dwarfs VII White dwarfs Table J 4 Luminosity Class Plotting the luminosity of stars against their spectral type surface temperature gives a diagram called a Hertzsprung Russell diagram after the two astronome
105. he closing speed of these collisions 1s generally extremely high tens or kilometres per second When such an object ploughs through the Earth s atmosphere a large amount of kinetic energy is converted into heat and light and a visible flash or streak can often be seen with the naked eye Even the smallest particles can cause these events which are commonly known as shooting stars While smaller objects tend to burn up in the atmosphere larger denser objects can penetrate the atmosphere and strike the surface of the planet sometimes leaving meteor craters Sometimes the angle of the collision means that larger objects pass through the atmo sphere but do not strike the Earth When this happens spectacular fireballs are sometimes seen Meteoroids is the name given to such objects when they are floating in space A Meteor is the name given to the visible atmospheric phenomenon Meteorites is the name given to objects that penetrate the atmosphere and land on the surface J 10 Eclipses Eclipses occur when an apparently large celestial body planet moon etc moves between the observer that s you and a more distant object the more distant object being eclipsed by the nearer one J 10 1 Solar Eclipses Solar eclipses occur when our Moon moves between the Earth and the Sun This happens when the inclined orbit of the Moon causes its path to cross our line of sight to the Sun In essence it is the observer falling under the shadow o
106. he square has two other bright stars nearby forming a distinctive triangle delta is at the head of this triangle in the direction of Cassi opeia class of variables all of which are pulsat ing high mass stars in the later stages of their evolution Delta Cephei is also a double star with a companion of magnitude 6 3 visible in binoculars 115 APPENDIX K SKY GUIDE Stellarium Name Other Name s Type Magnitude Location Guide Description M42 Orion Nebula Nebula 4 Almost in the middle of the area bounded by Orion s belt and the stars Saiph and Rigel The Orion Nebula is the brightest nebula visible in the night sky and lies at about 1 500 light years from earth It is a truly gigantic gas and dust cloud that extends for several hundred light years reaching almost halfway across the constellation of Orion The nebula contains a cluster of hot young stars known as the Trapezium and more stars are believed to be forming within the cloud HP 62223 La Superba Y Canum Venaticorum Star Forms a neat triangle with Phad and Alkaid in Ursa Major La Superba is a Carbon Star a group of relatively cool gigantic usually variable stars that have an outer shell containing high levels of carbon This shell is very ef ficient at absorbing short wavelength blue light giving carbon stars a distinctive red or orange tint 52 amp 53 Bootis Nu Boo
107. ich are in zone 1 num stars in zone n 4n int 4 The number of records is this file which are in zone n Table D 8 Zones section 72 D 2 STAR CATALOGUE FILE FORMAT APPENDIX D STAR CATALOGUE Name Offset Type Size Description hip int Hipparcos catalogue number component_ids unsigned char This is an index to an array of catalogue number suffixes The list is read from the stars_hip_component_ids c file The value of this field turns out to be the line number in the file 1 x0 int This is the position of the star relative to the central point in the star s zone in axis 1 xl int This is the position of the star relative to the central point in the star s zone in axis 2 b_v unsigned char This is the magnitude level in B V colour This value refers to one of 256 discrete steps in the magnitude range for the file mag 10 unsigned char This is the magnitude level in the V I colour This value refers to one of 256 discrete steps in the magnitude range for the file sp_int 11 unsigned short int This is the index in an array of spectral type descriptions which is taken from the file stars_hip_sp cat the index corresponds to the line number in the file 1 dx0 13 int This is the proper motion of the star in axis 1 dx 17 int This is the proper motion of the star in axis 2
108. ier S OO 154 JU JU Nora Lempa ff A f f Create json tot Copy to Cupbos Choos text _Clear All Close Screen display of the Equatorial to Decimal Converter Program The program in the picture can accept the corner coordinates of a texture in your plate solving program into decimal values and write an insert for the textures json file It is available as a freebee from http www madpc co uk peterv astroplover equipnbits Stellariumtextures zip H 0 17 Plate Solving Suitable programs that can accept your picture and calculate its corner coordinates are hard to find I have only found one that suits our purpose and it is another expensive planetarium program TheSkyX Pro However the older versions TheSky5 and 6 Pro will also do the job if suitably configured These programs have a link feature that can match your photo to the selected area of the screen and superimpose it on the display with a box around your photo provided it can match at least 5 stars from the GSC that is included with the program When this is fitted you can read the corner coordinates of your texture in the Status bar by selecting them with a mouse TheSkyX can read these coordinates in J2000 values but the earlier programs only read the coordinates of the current program date To read the J2000 coordinates it is necessary to re start the program with the date set to 1 1 2000 To add the picture to TheSky you need first make a mono 8 bit jpg version of
109. ig_halo string File name of a PNG or JPEG texture file to be used as the big halo image big_halo_size float The angular size of the big halo texture Typical values range between 10 and 200 coord_func string Select the method of calculating the orbit Possible values are ell_orbit comet_orbit lt planet gt _special specific calculations for major bodies lighting boolean Turn on or off lighting effects Shows the phase of the moon and planets albedo float Specify the albedo of the body rot_periode float Specify the rotational period of the body in hours rot_obliquity float Angle between rotational axis and perpendicular to orbital plane in degrees rot_equator_ascending_nodg float Rotational parameter sidereal_period float Rotational period in days orbit_Period float Time for one full orbit in days orbit_SemiMajorAxis float Keplarian orbital element orbit_Eccentricity float Keplarian orbital element orbit_Inclination float Keplarian orbital element orbit_AscendingNode float Keplarian orbital element orbit_LongOfPericenter float Orbital element used in ell_orbit calculations orbit_MeanLongitude float Orbital element used in ell_orbit calculations ascending float Orbital element used in ell_orbit calculations hidden boolean Display planet as seen from other bodies or not orbit_TimeAtPericenter float Object parameter used in comet_orbit calculations orbit_PericenterDistance float Object parameter used in comet_orbit calcula
110. ight it s giving out and how far it is from the observer Astronomers separate these factors by using two measures absolute 96 14 PRECESSION APPENDIX I ASTRONOMICAL CONCEPTS Object m M The Sun 27 4 8 Vega 0 05 0 6 Betelgeuse 0 47 7 2 Sirius the brightest star 1 5 1 4 Venus at brightest 4 4 Full Moon at brightest 12 6 Table I 2 Magnitudes of well known objects magnitude M which is a measure of how much light is being given out by an object and apparent magnitude m which is how bright something appears to be in the sky For example consider two 100 watt lamps one which is a few meters away and one which is a kilometre away Both give out the same amount of light they have the same absolute magnitude However the nearby lamp seems much brighter it has a much greater apparent magnitude When astronomers talk about magnitude without specifying whether they mean apparent or absolute magnitude they are usually referring to apparent mag nitude The magnitude scale has its roots in antiquity The Greek astronomer Hipparchus defined the brightest stars in the sky to be first magnitude and the dimmest visible to the naked eye to be sixth magnitude In the 19th century British astronomer Norman Pogson quantified the scale more precisely defining it as a logarithmic scale where a magnitude 1 object is 100 times as bright as a magnitude 6 object a difference of five m
111. imuthal_color float all Sets the colour of the azimuthal grid in R G B RGB values where 1 is the maximum e g 1 0 1 0 1 0 for white gui_base_color float 0 10 1 These three numbers determine the R G B colour of the interface in RGB values where 1 is the maximum e g 1 0 1 0 1 0 for white gui_text_color float 0 10 1 These three numbers determine the R G B colour of the text in RGB values where is the maximum e g 1 0 1 0 1 0 for white equatorial_color float Sets the colour of the equatorial grid R G B on date in RGB values where is the maximum e g 1 0 1 0 1 0 for white 52 APPENDIX A CONFIGURATION FILE continued Section ID Version Description equatorial_J2000_color float 0 10 2 Sets the colour of the equatorial grid R G B 32000 in RGB values where 1 is the maximum e g 1 0 1 0 1 0 for whiteDescriptionDescription galactic_color float 0 10 4 Sets the colour of the galactic grid in R G B RGB values where 1 is the maximum e g 1 0 1 0 1 0 for white galactic_plane_color float 0 11 2 Sets the colour of the galactic plane R G B line in RGB values where 1 is the maximum e g 1 0 1 0 1 0 for white equator_color float all Sets the colour of the equatorial line in R G B RGB values where 1 is the maximum e g 1 0 1 0 1 0 for white ecliptic_color float 0 11 3 Sets the colour of the ecliptic line R G B J2000 in RGB values where 1 is the maximum e g 1
112. ined as the amount of time that it takes for the Sun to travel from the highest point in the sky at mid day to the next high point on the next day In astronomy this is called a solar day The apparent motion of the Sun is caused by the rotation of the Earth However in this time the Earth not only spins it also moves slightly round it s orbit Thus in one solar day the Earth does not spin exactly 360 on it s axis Another way to measure day length is to consider how long it takes for the Earth to rotate exactly 360 This is known as one sidereal day Figure T 3Jillustrates the motion of the Earth as seen looking down on the Earth orbiting the Sun The red triangle on the Earth represents the location of an observer The figure shows the Earth at four times 1 The Sun is directly overhead it is mid day 2 Twelve hours have passed since 1 The Earth has rotated round and the observer is on the opposite side of the Earth from the Sun It is mid night The Earth has also moved round in it s orbit a little 3 The Earth has rotated exactly 360 Exactly one sidereal day has passed since 1 4 It is mid day again exactly one solar day since 1 Note that the Earth has rotated more than 360 since 1 It should be noted that in figure L3 the sizes of the Sun and Earth and not to scale More importantly the distance the Earth moves around it s orbit is much exaggerated In one real solar day the Earth takes a year to travel round th
113. into the void between galaxies J 8 Nebulae Seen with the naked eye binoculars or a small telescope a nebula plural nebulae are fuzzy patches on the sky Historically the term referred to any extended object but the modern definition excludes some types of object such as galaxies Observationally nebulae are popular objects for amateur astronomers they exhibit complex structure spectacular colours and a wide variety of forms Many nebulae are bright enough to be seen using good binoculars or small to medium sized telescopes and are a very photogenic subject for astro photographers Nebulae are associated with a variety of phenomena some being clouds of interstellar dust and gas in the process of collapsing under gravity some being envelopes of gas thrown off during a supernova event so called supernova remnants yet others being the remnants of solar systems around dead stars planetary nebulae Examples of nebulae for which Stellarium has images include the Crab Nebula M1 which is a supernova remnant and the Dumbbell Nebula M27 which is a planetary nebula J 9 Meteoroids These objects are small pieces of space debris left over from the early days of the solar system that orbit the Sun They come in a variety of shapes sizes an compositions ranging 109 J 10 ECLIPSES APPENDIX J ASTRONOMICAL PHENOMENA from microscopic dust particles up to about ten meters across Sometimes these objects collide with the Earth T
114. ion host_name string 0 10 3 Name of host for proxy E g proxy org port integer 0 10 3 Port of proxy E g 8080 user string 0 10 3 Username for proxy E g michael_knight password string 0 10 3 Password for proxy E g xxxxx Section scripts Section ID Version Description flag_script_allow_ui bool 0 9 1 scripting _allow_write_files bool 0 9 1 Section search Section ID Version Description flag_search_online bool 0 11 2 If true Stellarium will be use SIMBAD for search simbad_server_url string 0 11 2 URL for SIMBAD mirror flag_start_words bool 0 11 3 If false Stellarium will be search phrase only from start of words Section spheric_mirror Section ID Version Description distorter_max_fov float all Set the maximum field of view for the spheric mirror distorter in degrees Typical value 180 flag_use_ext_framebuffer_object bool all Some video hardware incorrectly claims to support some GL extension GL_FRAMEBUFFER_EXTEXT If when using the spheric mirror distorter the frame rate drops to a very low value e g 0 1 FPS set this parameter to false to tell Stellarium ignore the claim of the video driver that it can use this extension flip_horz bool all Flip the projection horizontally flip_vert bool all Flip the projection vertically projector_gamma float all This parameter controls the properties of the spheric mirror projection mode projector_positi
115. ist e Details of the new script engine will be found in Appendix E under construction 5 6 Visual Effects 5 6 1 Light Pollution Stellarium can simulate light pollution which is controlled from the light pollution section of the Sky tab of the View window Light pollution levels are set using an numerical value between 1 and 9 which corresponds to the Bortle Dark Sky Scale 31 5 6 VISUAL EFFECTS CHAPTER 5 ADVANCED USE Level Title Colour Limiting magnitude eye Description Excellent dark sky site black 7 6 8 0 Zodiacal light gegenschein zodiacal band visible M33 direct vision naked eye object Scorpius and Sagittarius regions of the Milky Way cast obvious shadows on the ground Airglow is readily visible Jupiter and Venus affect dark adaptation surroundings basically invisible Typical truly dark site grey 7 1 7 5 Airglow weakly visible near horizon M33 easily seen with naked eye highly structured Summer Milky Way distinctly yellowish zodiacal light bright enough to cast shadows at dusk and dawn clouds only visible as dark holes surroundings still only barely visible silhouetted against the sky many Messier globular clusters still distinct naked eye objects Rural sky blue 6 6 7 0 Some light pollution evident at the horizon clouds illuminated near horizon dark overhead Milky Way still appears complex M15 M4 M5 M22 distinct naked eye objects M
116. k Cover Text may be added by or through arrangements made by any one entity If the Document already includes a cover text for the same cover previously added by you or by arrangement made by the same entity you are acting on behalf of you may not add another but you may replace the old one on explicit permission from the previous publisher that added the old one 120 APPENDIX M GNU FREE DOCUMENTATION LICENSE The author s and publisher s of the Document do not by this License give permission to use their names for publicity for or to assert or imply endorsement of any Modified Version 5 COMBINING DOCUMENTS You may combine the Document with other documents released under this License under the terms defined in section 4 above for modified versions provided that you include in the combination all of the Invariant Sections of all of the original documents unmodified and list them all as Invariant Sections of your combined work in its license notice and that you preserve all their Warranty Disclaimers The combined work need only contain one copy of this License and multiple identical Invariant Sections may be replaced with a single copy If there are multiple Invariant Sections with the same name but different contents make the title of each such section unique by adding at the end of it in parentheses the name of the original author or publisher of that section if known or else a unique number Make the same adjustment to the se
117. ky When the name of an object to find is typed in the object window and you are connected to the internet and the Extended search is ticked Stellarium will search the on line SIMBAD data bases for its coordinates you can and then click the go button or press return Stel larium will point you at that object in the sky even if there is no object displayed on the screen The SIMBAD server being used can be selrscted from the scroll window The List Search window provides a convenient way to locate particular types of objects in the sky At the moment the number of choices is governed by the loaded plug ins Simply scroll down the first window to select the type The name of an object can then be selected from the list Press enter and stelarium will go to that object 15 3 1 TOUR CHAPTER 3 INTERFACE GUIDE 3 1 7 Help Window Figure 3 7 The help window help The help window3 7 lists all Stellarium s key strokes Not that some features are only available as key strokes so it s a good idea to have a browse of the information in this window The help window About tab will show licensing information and a list of people who helped to produce the program lists The help window log lists the loading instructions carried out when stellarium runs It is useful to locate the files that stellarium writes to you computer It is the master of the copy log txt that you will find in your user area 3 1 8 Help Keys Table
118. larium s configuration is done using the configuration window and the view window To open the configuration window click the 4 button on the left side tool bar or press F2 To open the view window click the Y button if the left side tool bar or press F4 Some options may only be configured by editing the configuration file See section 4 for more details Date and Time 2008 10 16 14 46 56 Figure 4 1 Date amp Time window 4 1 Setting the Date and Time In addition to the time rate control buttons on the main tool bar you can use the date and time window to set the simulation time figure K T The values for year month day hour minutes and seconds may be modified by typing new values by clicking the up and down arrows above and below the values and by using the mouse wheel 4 2 Setting the time zone The time zone will default to the settings of your computer system This is not always the desired setting To get around this a plug in has been developed that now allows setting of the time zone independantly of your computer See the timezone plug ins 4 3 Setting Your Location The positions of the stars in the sky is dependent on your location on Earth or other planet as well as the time and date For Stellarium to show accurately what is or will be was in the sky you must tell it where you are You only need to do this once Stellarium can save your location so you won t need to set it again until you move
119. llarium s visual effects including constellation line and boundary drawing constellation art planet hints and atmospheric fogging around the bright Moon The controls main tool bar provides a mechanism for turning on and off the visual effects Figure 3 4 Screenshot showing off some of Stellarium s visual effects 3 1 5 Main Tool bar When the mouse if moved to the bottom left of the screen a second tool bar becomes visible All the buttons in this side tool bar open and close dialog boxes which contain controls for further configuration of the program Table 3 6 describes the operations of buttons on the main tool bar and the side tool bar and gives their keyboard shortcuts 13 3 1 TOUR CHAPTER 3 INTERFACE GUIDE Feature Tool bar button Key Description if Constellations c Draws the constellation lines 1A Constellation Names t v Draws the name of the constellations Y Constellation Art R r Superimposes artistic representations of the constellations over the stars Equatorial Grid 5 e Draws grid lines for the RA Dec coordinate Azimuth Grid Z Draws grid lines for the Alt Azi coordinate Toggle Ground sf g Toggles drawing of the ground Turn this off to see objects below the horizon Toggle Cardinal Points q Toggles marking of the North South East and West points on the horizon Toggle Atmosphere amp a Toggles atmospheric effects Notably mak
120. m starts up and settings such as the observer s location and display preferences are taken from it Ideally this mechanism should be totally transparent to the user anything that is configurable should be configured in the program GUI However at time of writing Stellarium isn t quite complete in this respect despite improvements in version 0 10 0 Some settings can only be changed by directly editing the configuration file This section describes some of the settings a user may wish to modify in this way and how to do it If the configuration file does not exist in the user directory when Stellarium is started e g the first time the user starts the program one will be created with default values for all settings refer to section 5 1 for the location of the user directory on your operating system The name of the configuration file is config in iP The configuration file is a regular text file so all you need to edit it is a text editor like Notepad wordpad on Windows Text Edit on the Mac or nano vi gedit etc on Linux The following sub sections contain details on how to make commonly used modifica tions to the configuration file A complete list of configuration file values may be found in appendix 3It is possible to specify a different name for the main configuration file using the config file com mand line option See section 5 3 for details 29 5 3 COMMAND LINE OPTIONS CHAPTER 5 ADVANCED USE
121. mission of the European Space Agency ESA dedicated to the measurement of stellar parallax and the proper motions of stars The project was named in honour of the Greek astronomer Hipparchus Ideas for such a mission dated from 1967 with the mission accepted by ESA in 1980 The satellite was launched by an Ariane 4 on 8 August 1989 The original goal was to place the satellite in a geostationary orbit above the earth however a booster rocket failure resulted in a highly elliptical orbit from 315 to 22 300 miles altitude Despite this difficulty all of the scientific goals were accomplished Communications were terminated on 15 August 1993 The program was divided in two parts the Hipparcos experiment whose goal was to measure the five astrometric parameters of some 120 000 stars to a precision of some 2 to 4 milli arc seconds and the Tycho experiment whose goal was the measurement of the astrometric and two colour photometric properties of some 400 000 additional stars to a somewhat lower precision The final Hipparcos Catalogue 120 000 stars with 1 milli arc second level astrometry and the final Tycho Catalogue more than one million stars with 20 30 milli arc second astrometry and two colour photometry were completed in August 1996 The catalogues were published by ESA in June 1997 The Hipparcos and Tycho data have been used to create the Millennium Star Atlas an all sky atlas of one million stars to visual magnitude 11 from the Hipparcos
122. n the advanced use in section 5 x x F 0 11 The Skycultures Folder Firstly your primary folder will need a name that represents your culture and can be called from the configuration file This folder can contain All of the drawings textures in png format that you wish to display An ASCII file star_names fab It contains the chosen culture names for significant stars An ASCII file constellation_names eng fab It contains the constellation names in Eng lish An ASCII file constellationsboundaries dat Contains the corner coordinates of con stellation An ASCII file constellationart fab Contains coordinates for three significant stars in the texture An ASCII file constellationship fab Contains the cordinate stars for constellation lines An ASCII file info ini Contains the base name Any number of description xx utf8 files containing specific languages information for display If the proposed file does not have any specific information to the culture it need not be present When developing a new culture for display it will help if you look at one of the existing cultures eg western and just change the entries specific to your new culture If you use a line in the file as a comment precede that line with and it will be ignored for the display 81 APPENDIX F CREATING NEW SKY CULTURES IN STELLARIUM F 0 11 1 Writing Your Own Sky Culture Files F 0 11 2 Figurename png Each texure is a square of sides 128x128 256x256 512x5
123. n fields are used so the actual resolution on the sky isn t significantly worse for the type 1 and 2 records in practice 71 D 2 STAR CATALOGUE FILE FORMAT APPENDIX D STAR CATALOGUE Name Offset Type Size Description Magic 0 int The magic number which identifies the file as a star catalogue Oxde0955a3 Data Type 4 int This describes the type of the file which defines the size and structure of the Star Data record for the file Major Version 8 int The file format major version number Minor Version 12 int The file format minor version number Level 16 int Sets the level of sub division of the geodesic sphere used to create the zones O means an icosahedron 20 sizes subsequent levels of sub division lead to numbers of Magnitude Minimum 20 int zones as described in section D 1 1 The low bound of the magnitude scale for values in this file Note that this is still an integer in Stellarium s own internal representation Magnitude Range 24 int The range of magnitudes expressed in this file Magnitude Steps 28 int The number of steps used to describes values in the range Table D 6 Header Record Name Offset Type Size Description num stars in zone 0 0 int 4 The number of records in this file which are in zone 0 num stars in zone 1 4 int 4 The number of records is this file wh
124. n the programs mentioned or similar programs on the preferred system A most important part of Stellarium has been the ability to make and run presentations of astronomical events using the display power of Stellarium The original script engine that was part of the early versions was very limited in what it could do Commencing with verion 0 10 2 a new script engine has been under development that is very powerful and can be expanded as necessary After five years of development the new script engine has reached a stage where it can cater fror almost every requirement However it can now have new commands implemented as necessary using the basic Stellarium core G 0 12 The Script A script is a text file that can be prepared with any text editor and read by Stellarium to display an astronomical event such as a past or future eclipse or a display of features of Stellarium with sound and video The possibilities are extensive and only limited by what commands are available in the Stellarium core code Here is an example of a simple script that displays a lunar eclpse from 2006 Note that each command ends with It has been modfied from the original to return the screen to the starting state when finished Name Partial Lunar Eclispe License Public Domain Author Matthew Gates Modified B Gerdes 09 02 2009 Description Attempt to re implement simple script from the old scripting engine Each old style command is shown
125. name of the directory should be unique to your landscape and is the landscape ID The convention is to use a single descriptive word in lowercase text for example gueriens Place your pictures your new directory 5 In your new landscape directory create a new file called Landscape ini file I used wordpad Add a line for the landscape section It s probably easiest to copy the landscape ini file for the Gueriens landscape and edit it Edit the name Guereins in every instance to the name you have given your landscape Don t forget to make the number of t ex entries agree with the number of your pictures If you haven t made a groundtex picture use one of the existing ones from the file or make a square blank picture of your own idea Because I took my pictures from the roof of the house I used an edited picture of the roof of my house from Google Earth It was pretty cruddy low resolution but served the purpose 6 Next you need to orientate your picture North with true North This is done roughly by making the arrangement of sidel to siden suit your site as close as possible Now you need to edit the value of decor_angle_rotatez to move your land scape in azimuth Edit decor_alt_angle to move you landscape in altitude to align your visible horizon angle Edit ground_angle_rotatez to align your ground with the rest of the landscape Leave the other entries they are suitable as is After re starting Stellarium your landscape will appear in
126. nd A similar thing happens due to the Earth s motion around the Sun Nearby stars appear to move against more distant background stars as illustrated in figure L6 The movement of nearby stars against the background is called stellar parallax or annual parallax Since we know the distance the radius of the Earth s orbit around the Sun from other methods we can use simple geometry to calculate the distance of the nearby star if we measure annual parallax In figure L6 the annual parallax p is half the angular distance between the apparent positions of the nearby star The distance of the nearby object is d Astronomers use a unit of distance called the parsec which is defined as the distance at which a nearby star has p 1 Even the nearest stars exhibit very small movement due to parallax The closest star to the Earth other than the Sun is Proxima Centuri It has an annual parallax of 0 77199 corresponding to a distance of 1 295 parsecs 4 22 light years 98 L5 PARALLAX APPENDIX I ASTRONOMICAL CONCEPTS Polaris an ecliptic xo a South pole Figure 1 5 Precession fathom aay d View from Earth in January View from Earth in July Figure I 6 Apparent motion due to parallax 99 L6 PROPER MOTION APPENDIX I ASTRONOMICAL CONCEPTS Even with the most sensitive instruments for measuring the positions of the stars it is only possible to use parallax to determine the distance of s
127. nse does not apply to the other works in the aggregate which are not themselves derivative works of the Document If the Cover Text requirement of section 3 is applicable to these copies of the Document then if the Document is less than one half of the entire aggregate the Document s Cover Texts may be placed on covers that bracket the Document within the aggregate or the electronic equivalent of covers if the Document is in electronic form Otherwise they must appear on printed covers that bracket the whole aggregate 8 TRANSLATION Translation is considered a kind of modification so you may distribute translations of the Document under the terms of section 4 Replacing Invariant Sections with translations requires special permission from their copyright holders but you may include translations of some or all Invariant Sections in addition to the original versions of these Invariant Sections You may include a translation of this License and all the license notices in the Document and any Warranty Disclaimers provided that you also include the original English version of this License and the original versions of those notices and disclaimers In case of a disagreement between the translation and the original version of this License or a notice or disclaimer the original version will prevail If a section in the Document is Entitled Acknowledgements Dedications or History the requirement section 4 to Preserve its Title section 1 will
128. nsider taking a deck chair and take a flask of hot drink Dark adaptation The true majesty of the night sky only becomes apparent when the eye has had time to become accustomed to the dark This process known as dark adapt ation can take up to half and hour and as soon as the observer sees a bright light they must start the process over Red light doesn t compromise dark adaptation as much as white light so use a red torch if possible and one that is as dim as you can manage with A single red LED light is ideal The Moon Unless you re particularly interested in observing the Moon on a given night it can be a nuisance it can be so bright as to make observation of dimmer objects such as nebulae impossible When planning what you want to observe take the phase and position of the Moon into account Of course Stellarium is the ideal tool for finding this out Averted vision A curious fact about the eye is that it is more sensitive to dim light towards the edge of the field of view If an object is slightly too dim to see directly looking slightly off to the side but concentrating on the object s location can often reveal it Angular distance Learn how to estimate angular distances Learn the angular distances described in section If you have a pair of binoculars find out the angular distance across the field of view 5 and use this as a standard measure J 13 Handy Angles Being able to estimate angular distance can be very u
129. nternet Observability This shows times and availabilty of objects you may wish to see and SolarSystemEditor This can be used to find and include orbital data on Solar System objects and added to the ssystem ini file Solar System objects setungs Configuration file lar S Figure 5 10 Observability and Solar system editor 47 5 13 PLUG INS CHAPTER 5 ADVANCED USE SuperNova A list of Super Novas that can be displayed from an editable data base SN 1604A Kepler s Supernova 1604A Figure 5 11 Historical Supernova display When Historical SuperNova is active follow the instructions from the plugin screen to display the supernova To see the representation will require resetting the date to the listed date as these phenomena fade within months of the explosion and the object will disappear leaving a faint expanding planetary nebula Telescope Control he A simple interface to control a telescope from the Stellarium screen Figure 5 12 Telescope control Stellarium has a simple control mechanism for motorised telescope mounts The user selects an object i e by clicking on something a planet a star etc and presses the telescope go to key see section and the telescope will be guided to the object The control interface uses the Meade or the Celestron protocol and most telescopes use either one or the other so many different brands of telescopes can be controlled There is a third party Telescope control
130. nu screen or by a text editor 45 5 13 PLUG INS CHAPTER 5 ADVANCED USE Pulsars A list of Pulsars that can be displayed from an editable data base Figure 5 6 Pulsar locations When active this plug in reads the associated pulsars json file and places in blue around the pulsar with a name 050 Quasars A list of Quasars that can be displayed from an editable data base Figure 5 7 Quasar locations When active this plug in reads the associated pulsars json file and places in red around the pulsar with a name RendererStatistics VA list of statisics from the operation of the program Figure 5 8 Renderer statistics When activated displays statistics about the renderer 46 5 13 PLUG INS CHAPTER 5 ADVANCED USE Satellites This displays a number of earth orbiting satellies automatically updated every 72 hours from the internet Figure 5 9 Satellite locations This plug in reads information on a selected range of near earth orbiting satellites from a file satellites json that is updated every 72 hoursand displays y with a name The file 1s editable with a text editor to change the colour and visibility when required If you are not connected to the internet the satellites json file will not get updated This can cause odd effects on the screen if the satellite has crashed back to Earth When this happens it is necessary to have the stellites json file updated automatically by a connection to the i
131. on_x float all projector_position_y float all projector_position_z float all mirror_position_x float all mirror_position_y float all mirror_position_z float all mirror_radius float all dome_radius float all zenith_y float all scaling_factor float all 61 APPENDIX A CONFIGURATION FILE Section stars Section ID Version Description relative_scale float all Changes the relative size of bright and faint stars Higher values mean that bright stars are comparitively larger when rendered Typical value 1 0 absolute_scale float all Changes how large stars are rendered larger value lead to larger depiction Typical value 1 0 star_twinkle_amount float all Sets the amount of twinkling Typical value 0 3 flag_star_twinkle bool all Set to false to turn star twinkling off true to allow twinkling flag_point_star bool all Set to false to draw stars at a size that corresponds to their brightness When set to true all stars are drawn at single pixel size mag_converter_max_fov float all Sets the maximum field of view for which the magnitude conversion routine is used Typical value 90 0 mag_converter_min_fov float all Sets the minimum field of view for which the magnitude conversion routine is used Typical value 0 001 labels_amount float all Sets the amount of labels Typical value 3 0 init_bortle_scale integer all Sets
132. one of the first tasks for an amateur observer is learning the constellations the process of becoming familiar with the relative positions of the constellations at what time of year a constellation is visible and in which constellations observationally interesting objects reside Internationally astronomers have adopted the Western Greek Roman con stellations as a common system for segmenting the sky As such some formalisation has been adopted each constellation having a proper name which is in Latin and a three letter abbreviation of that name For example Ursa Major has the abbreviation UMa I Contributions of artwork for these sky cultures would be very welcome post in the forums if you can help 102 J 2 STARS APPENDIX J ASTRONOMICAL PHENOMENA Fomalhaut a PsA HP 113368 Magnitude 1 15 B V 0 13 J2000 RA DE 22h57m39 0s 29 37 20 2 Equ of date RA DE 22h58m5s 29 34 45 Az Alt 308 29 40 63 59 24 Parallax 0 13008 Distance 25 07 Light Years Spectral Type A3V Figure J 2 Stellarium displaying information about a star J 2 4 Star Names Stars can have many names The brighter stars often have common names relating to myth ical characters from the various traditions For example the brightest star in the sky Sirius is also known as The Dog Star the name Canis Major the constellation Sirius is found in is Latin for The Great Dog There are several more formal naming conventions th
133. ool 0 10 2 Set to true if you want to see the equatorial grid J2000 on start up flag_ecliptic_J2000_grid bool 0 11 3 Set to true if you want to see the galactic plane line on start up flag_galactic_grid bool 0 10 4 Set to true if you want to see the galactic grid on start up flag_galactic_plane_line bool 0 11 2 Set to true if you want to see the galactic plane line on start up flag_equator_line bool all Set to true if you want to see the equator line on start up flag_ecliptic_line bool all Set to true if you want to see the ecliptic line J2000 on start up flag_meridian_line bool 0 8 0 Set to true if you want to see the meridian line on start up 63 APPENDIX A CONFIGURATION FILE continued Section ID Version Description flag_cardinal_points bool all Set to false if you don t want to see the cardinal points flag_gravity_labels bool all Set to true if you want labels to undergo gravity top side of text points toward zenithzenith Useful with dome projection flag_init_moon_scaled bool 0 6 2 Change to false if you want to see the real moon size on start up viewing _mode string 0 6 2 flag_moon_scaled bool 0 7 1 Change to false if you want to see the real moon size on start up moon_scale float all Sets the moon scale factor to correlate to our perception of the moon s size Typical value 4 constellation_art_intensity float all This number multiplies th
134. or this landscape Note that the name of the section in this case moon must be the landscape ID i e the same as the name of the directory where the Landscape ini file exists 5 7 3 Multiple Image Method The multiple image method works by having a360 panorama of the horizon split into a number of smaller side textures and a separate ground texture This has the advantage over the single image method that the detail level of the horizon can be increased further without ending up with a single very large image file The ground texture can be a lower resolution than the panorama images Memory usage may be more efficient because there are no unused texture parts like the corners of the texture file in the fish eye method On the negative side it is more difficult to create this type of landscape merging the ground texture with the side textures can prove tricky The contents of the landscape ini file for this landscape type is also somewhat more complicated than for other landscape types Here is the landscape ini file which describes the Guereins landscape landscape name Guereins type old_style nbsidetex 8 tex0 guereins4 png texl guereins5 png tex2 guereins6 png tex3 guereins7 png tex4 guereins8 png tex5 guereinsl png tex6 guereins2 png tex7 guereins3 png nbside 8 SideO tex0 0 0 005 1 1 Sidel tex1 0 0 005 1 1 Side2 tex2 0 0 005 1 1 Side3 tex3 0 0 005 1 1 side4 tex4 0
135. orm the ground This last requirement is only really possible if this area is relatively featureless as the problem of knitting a complex base is well nigh impossible e Patience Maybe a soundproof room so that the swearing wont be heard when you press the wrong key and lose an hours work E 0 5 The Camera Digital cameras are easy and cheaply available these days so whatever you have should do One mega pixel resolution is quite sufficient The camera needs to be mounted on a tripod so that reasonably orientated pictures can be taken Select a time of day that is quite bright with a neutral cloudy sky so there will be 75 APPENDIX E CREATING A PERSONALISED LANDSCAPE FOR STELLARIUM no shadows and a sky of the same overall texture This will make it easier to remove later The pictures were all saved in the JPG format which was used as the common format for all processes up to the removal of the background With a camera that takes 4 3 ratio pictures I found 14 evenly spaced pictures gave the best 360 panorama in the program I used to produce it E 0 6 Processing into a Panorama This is the most complicated part of the process of generating the panorama I used two separate programs to do this Firstly I used The Gimp to resize the pictures to 1024x768 pixels and so make them easier to handle in the panorama program When I had my 14 processed pictures I inserted them into the panorama program I used a program called the Panoram
136. ound the celestial sphere that is half way between the celestial poles just as the Earth s equator is the line half way between the Earth s poles 12 Coordinate Systems 12 1 Altitude Azimuth Coordinates The Altitude Azimuth coordinate system can be used to describe a direction of view the azimuth angle and a height in the sky the altitude angle The azimuth angle is measured 93 12 COORDINATE SYSTEMS APPENDIX I ASTRONOMICAL CONCEPTS North pole South pole nadir Figure 1 2 Right Ascension amp Declination clockwise round from due North Hence North itself is East 90 Southwest is 135 and so on The altitude angle is measured up from the horizon Looking directly up at the zenith would be 90 half way between the zenith and the horizon is 45 and so on The point opposite the zenith is called the nadir The Altitude Azimuth coordinate system is attractive in that it is intuitive most people are familiar with azimuth angles from bearings in the context of navigation and the altitude angle is something most people can visualise pretty easily However the altitude azimuth coordinate system is not suitable for describing the gen eral position of stars and other objects in the sky the altitude and azimuth values for an object in the sky change with time and the location of the observer Stellarium can draw grid lines for altitude azimuth coordinates Use the button on the main tool bar to activate
137. oundaries and control the brightness of the constellation artwork Projection Selecting items in this list changes the projection method which Stellarium uses to draw the sky Options are cylinder The full name of this projection mode is cylindrical equidistant projection The maximum field of view in this mode is 233 equal area The full name of this projection method is Lambert azimuthal equal area projection The maximum field of view is 360 fisheye Stellarium draws the sky using azimuthal equidistant projection In fish eye projection straight lines become curves when they appear a large angular distance from the centre of the field of view like the distortions seen with very wide angle camera lenses This is more pronounced as the user zooms out The maximum field of view in this mode is 180 Hammer Aitoff The Hammer projection is an equal area map projection described by Ernst Hammer in 1892 and directly inspired by the Aitoff projection The maximum field of view in this mode is 360 mercator Mercator projection preserves the angles between objects and the scale around an object the same in all directions The maximum field of view in this mode is 233 orthographic Orthographic projection is related to perspective projection but the point of perspective is set to an infinite distance The maximum field of view is 180 perspective Perspective projection keeps the horizon a straight line The maximum field of vie
138. r Eclipse Find a Solar Eclipse using Stellarium amp take a screenshot of it 118 Appendix M GNU Free Documentation License Version 1 2 November 2002 Copyright C 2000 2001 2002 Free Software Foundation Inc 51 Franklin St Fifth Floor Boston MA 02110 1301 USA Everyone is permitted to copy and distribute verbatim copies of this license document but changing it is not allowed 0 PREAMBLE The purpose of this License is to make a manual textbook or other functional and useful document free in the sense of freedom to assure everyone the effective freedom to copy and redistribute it with or without modifying it either commercially or noncommercially Secondarily this License preserves for the author and publisher a way to get credit for their work while not being considered responsible for modifications made by others This License is a kind of copyleft which means that derivative works of the document must themselves be free in the same sense It complements the GNU General Public License which is a copyleft license designed for free software We have designed this License in order to use it for manuals for free software because free software needs free documentation a free program should come with manuals providing the same freedoms that the software does But this License is not limited to software manuals it can be used for any textual work regardless of subject matter or whether it is published as a printed book We r
139. r details of the file format A new method of displaying textures using the json cataloguing system was adopted after 0 10 x that does not need this file for displaying textures At the same time the Simbad online catalogue was added to the search feature making it largely redundant and used now only as a first search point or if there is no internet connection If the object has a name not just a catalogue number you should add one or more records to the nebulae default ngc2000names dat file See section 5 8 2 for details of the file format If you wish to associate a texture image with the object you must now add a record to the nebulae default textures json file See section 5 8 3 for details of the file format Nebula images should have dimensions which are integer powers of two i e 1 2 4 8 16 32 64 128 256 512 1024 pixels along each side If this requirement is not met your textures may not be visible or graphics performance may be seriously impacted PNG or JPG formats are both supported 5 8 1 Modifying ngc2000 dat Each deep sky image has one line inthengc2000 dat file in the nebulae default directory where is either the installation directory or the user directory The file is a is now a compressed ASCII file and cannot edited with a normal text editor However it is no longer necessary to edit it for any reason Each line contains one record each record consisting of the following
140. r float all Sets the colour of the cardinal points in R G B RGB values where 1 is the maximum e g 1 0 1 0 1 0 for white 53 APPENDIX A CONFIGURATION FILE continued Section ID Version Description planet_names_color float all Sets the colour of the planet names in R G B RGB values where 1 is the maximum e g 1 0 1 0 1 0 for white Description planet_orbits_color float all Sets the colour of the orbits in RGB R G B values where 1 is the maximum e g 1 0 1 0 1 0 for white object_trails_color float all Sets the colour of the planet trails in R G B RGB values where 1 is the maximum e g 1 0 1 0 1 0 for white chart_color float 0 8 0 Sets the colour of the chart in RGB R G B 0 8 2 values where 1 is the maximum e g 1 0 1 0 1 0 for white telescope_circle_color float all Sets the colour of the telescope R G B location indicator RGB values where 1 is the maximum e g 1 0 1 0 1 0 for white telescope_label_color float all Sets the colour of the telescope R G B location label RGB values where 1 is the maximum e g 1 0 1 0 1 0 for white script_console_keyword_color float 0 10 5 Sets the colour of the keywords in the R G B script console RGB values where 1 is the maximum e g 1 0 1 0 1 0 for white script_console_module_color float 0 10 5 Sets the colour of the modules in the R G B script console RGB values where 1 is the maximum e g 1 0 1 0 1 0 for white
141. r setFlagFog Boolean True or false SolarSystem setFlagOrbits Boolean True or false SolarSystem setFlagPlanets Boolean True or false SolarSystem setLabelsAmount 20 StarMgr setLabelsAmount sl Table G 4 Table of scripting Commands 86 APPENDIX G CREATING SCRIPTS FOR STELLARIUM Command Description StelMovementMgr autozoomIn x Zooms in to the object in x number of seconds StelMovementMgr autozoomOut x Zooms back to previous view in x number of seconds StelMovementMgr zoom x y Zooms to a specific FOV where 6699 x is the FOV in degrees and y the number of seconds StelMovementMer zoomTo x y StelMovementMgr setFlagTracking boolean True or false StelSkyDrawer setFlagLuminanceAdaptation True or false Boolean StelSkyImageMgr showImage image Image name boolean True or false Table G 6 Table of scripting Commands G 0 14 Progam Architecture Program Architecture The code of Stellarium is split into several main blocks The main loop and main widget classes StelMainWindow StelMainGraphics View and StelAppGraphics Widget Those classes have a single instance created at startup by the main function They perform tasks such as creating of the main window and renderer creating the stellarium core creating the GUI After initialization they manage user s input event propagation
142. ram Syntax is extremely important Look at the file with a text editor to see the format Items in lt gt are user provided strings and values to suit the texture and source Line imageCredits short lt name of source gt infoUrl http lt web address gt Line 2 imageUrl lt location and name of image gt Line 3 worldCoords lt decimal numerical values of the J2000 coordinates of the corners of the texture gt These values displayed to 4 decimal places in the format of the texture coordinates Line 4 textureCoords 0 0 1 0 1 1 0 1 Where 0 0 is South Left 1 0 the South Right 1 1 North Right 0 1 North Left corners of texture Format RA in degrees Dec in degrees Line 5 MinResolution lt a numerical value that displays the texture gt Line 6 maxBrightness lt a numerical vale representing the absolute brightness for the display gt Calculating of the coords of the corners of the images plate solving is a time consuming project and needs to be fine tuned from the screen display As most images will be two dimensional display on a spherical display will limit the size to about 1 degree before distortion becomes evident Larger displays can be sectioned into a mosaic of smaller textures for a more accurate display The textures json file which ships with Stellarium is actually a simplified version of the file format It is possible for a subTile to itself
143. rectory in the nebulae directory stars contains Stellarium s star catalogues In future Stellarium will be able to support multiple star catalogues and switch between them at runtime This feature is not implemented for version 0 10 0 although the directory structure is in place each star catalogue has it s own sub directory in the stars directory scripts contains any miscellaneous scripts that you wish to preserve in the scripts directory This is a good place to store any of your old sts scripts that may still work when the read stratoscripts feature is enabled at compile time data contains miscellaneous data files including fonts solar system data city locations etc textures contains miscellaneous texture files such as the graphics for the toolbar buttons planet texture maps etc If any file exists in both the installation directory and user directory the version in the user directory will be used Thus it is possible to override settings which are part of the main Stellarium installation by copying the relevant file to the user area and modifying it there It is also possible to add new landscapes by creating the relevant files and directories within the user directory leaving the installation directory unchanged In this manner dif ferent users on a multi user system can customise Stellarium without affecting the other users 5 2 The Main Configuration File The main configuration file is read each time Stellariu
144. referece a json file which contains multiple images The more general file format also includes some extra structures allowing for more meta data 5 8 4 Editing Image Files Images files should be copied to the nebulae lt set gt directory where lt set gt 1s the name of the nebula texture set to be modified which is usually default Images should be in PNG or JPEG format Images should have an aspect ratio of 1 i e it should be square and should have a width amp height of 2 pixels where n is a positive integer i e 2 4 8 16 32 64 128 256 512 and so on Black is interpretted as being 100 transparent Ensure that the background of the image is totally black i e has RGB values 0 0 0 and not just nearly black since this can cause an ugly square around the object There is a lot of software which may be used to create modify PNG and JPEG images The author recommends the GNU Image Manipulation Program TheGimp GIMP since it is more than up to the job and is free software in the same spirit as Stellarium itself 5 9 Sky Cultures Sky cultures are defined in the skycultures directory which may be found in the installation directory and or user directory Inside is one sub directory per sky culture each of these containing settings and image files as described in table 5 6 Section names should be unique within the ssystem ini file File Purpose 39 5 10 ADDING PLANETARY BODIES CHA
145. rendered directly in the graphics window User actions trigger signals connected to core and StelModules slots The script engine StelScriptMgr allows scripts to calls slots from the core and StelM odule slots 87 APPENDIX G CREATING SCRIPTS FOR STELLARIUM rastas and it E main StelMainWindow amp StelMainGraphicsView Creates and int O s Ta StelScriptMgr z ES src scripting f StelAppGraphicsWidget TA Jews and int StelGui StelApp i dizs a Core Services i Core Modules Plugins Modules StelCore CompassMarks StelRenderer StarMgr VirGO StelFileMgr NebulaMgr StelLocaleMgr SolarSystem fi StelAudioMgr ConstellationMgr i Ipiugins StelSkyLayerMgr MeteorMgr t StelModuleMgr TelescopeMgr StelSkyCultureMgr LandscapeMgr StelObjectMgr GridLinesMgr StelDownloadMgr his MilkyWay StelLocationMgr ow e src core modules Figure G 1 Script Architexture G 0 15 Scripting Engine The details of the scripting engine for developing can be found in the API documentation and is beyond the scope of the User manual See the full API documentation at http stellarium org doc head and go to the section on Scripting This section is under contruction 88 Appendix H Adding Extra Deep Sky Photos tor Stellarium by Barry Gerdes 01 03 2014 This document describes how to add photos to Stellaruium H 0 16 Preparing a photo for inclusion
146. riant Sections are certain Secondary Sections whose titles are designated as being those of Invariant Sections in the notice that says that the Document is released under this License If a section does not fit the above definition of Secondary then it is not allowed to be designated as Invariant The Document may contain zero Invariant Sections If the Document does not identify any Invariant Sections then there are none The Cover Texts are certain short passages of text that are listed as Front Cover Texts or Back Cover Texts in the notice that says that the Document is released under this License A Front Cover Text may be at most 5 words and a Back Cover Text may be at most 25 words A Transparent copy of the Document means a machine readable copy represented in a format whose specification is available to the general public that is suitable for revising the document straightforwardly with generic text editors or for images composed of pixels generic paint programs or for drawings some widely available drawing editor and that is suitable for input to text formatters or for automatic translation to a variety of formats suitable for input to text formatters A copy made in an otherwise Transparent file format whose markup or absence of markup has been arranged to thwart or discourage subsequent modification by readers is not Transparent An image format is not Transparent if used for any substantial amount of text A copy that is not Tr
147. rium simulates light pollution and is calibrated to the Bortle Dark Sky Scale where I means a good dark sky and 9 is a very badly light polluted sky See section 5 6 I for more information Planets and satellites this group of options lets you turn on and off various features related to the planets Simulation of light speed will give more precise positions for planetary bodies which move rapidly against backround stars e g the moons of Jupiter The Scale Moon option will increase the apparent size of the moon in the sky which can be nice for wide field of view shots Labels and markers you can independantly change the amount of labels displayed for planets stars and nebuulae The further to the right the sliders are set the more labels you will see Note that more labels will also appear as you zoom in Shooting stars Stellarium has a simple meteor simulation option This setting controls how many shooting stars will be shown Note that shooting stars are only visible 24 4 5 THE VIEW SETTINGS WINDOW CHAPTER 4 CONFIGURATION when the time rate is 1 and might not be visiable at some times of day Meteor showers are not currently simulated 4 5 2 Marking Tab The Markings tab of the View window 4 6 controls the following features Celestial sphere this group of options makes it possible to plot various grids and lines in the main view Constellations these controls let you turn on and off constellation lines names art and b
148. round Another method of moving is to select some object in the sky left click on the object and press the Space key to centre the view on that object Similarly selecting an object and pressing the forward slash key will centre on the object and zoom right in on it 3 1 3 Zooming in and out The forward slash and backslash keys auto zoom in an out to different levels depending on what is selected Figure 3 2 If the object selected is a planet or moon in a sub system with a lot of moons e g Jupiter the initial zoom in will go to an intermediate level where the whole sub system should be visible Figure 3 2 Screenshot showing Stellarium zoomed out A second zoom will go to the full zoom level on the selected object Figure 3 3 Sim ilarly if you are fully zoomed in on a moon of Jupiter the first auto zoom out will go to the sub system zoom level Subsequent auto zoom out will fully zoom out and return the initial direction of view For objects that are not part of a sub system the initial auto zoom in will zoom right in on the selected object the exact field of view depending on the size type of the selected object and the initial auto zoom out will return to the initial FOV and direction of view 12 3 1 TOUR CHAPTER 3 INTERFACE GUIDE Figure 3 3 Screenshot showing Stellarium zoomed in 3 1 4 Display of other Features Stellarium can do a whole lot more than just draw the stars Figure 3 4 shows some of Ste
149. rs Ejnar Hertzs prung and Henry Norris Russell who devised it A slight variation of this is see in figure 104 J 2 STARS APPENDIX J ASTRONOMICAL PHENOMENA Spectral Class 10 100 000 Supergiants 10 000 Ib 5 j Il Bright 1 000 Giants Ill Giants gt Qn 100 0 Jo cc a po 10 Si IV Subgiants 23 wn oll c 1 5 a su a V Main Sequence 0 1 0 01 10 0 001 0 0001 15 White Dwarfs 0 00001 0 0 0 5 1 0 1 5 2 0 Colour B V Figure J 3 Plot of star colour vs magnitude 105 J 3 OUR MOON APPENDIX J ASTRONOMICAL PHENOMENA J 3 which is technically a colour magnitude plot J 2 6 Variables Most stars are of nearly constant luminosity The Sun is a good example of one which goes through relatively little variation in brightness usually about 0 1 over an 11 year solar cycle Many stars however undergo significant variations in luminosity and these are known as variable stars There are many types of variable stars falling into two categories intrinsic and extrinsic Intrinsic variables are stars which have intrinsic variations in brightness that is the star itself gets brighter and dimmer There are several types of intrinsic variables probably the best known and more important of which is the Cepheid variable whose luminosity is related to the period with which it s brightness varies Since the luminosity and therefore absolute magnitude can be calculated Cepheid variables may be used to
150. rsion of the panorama and use in Stellarium as your landscape Drag the screen around so it produces a centralised picture on the Stellarium screen at the highest resolution possible such that a circular portion will cover just cover the lowest part of the main panorama and take a screen shot This screen shot can be then processed into a quite effective ground texture that can be adjusted to match the rest of the panorama Figure E 6 Sphrerical Panorama ground panel 1 Make a new directory etc for the landscape 2 You can make it fit using the variable in the landscape ini file decor_alt_angle xx decor_angle_shift xx and decor_angle_rotatez xx Then the ground can be matched with ground_angle_shift xx and ground_angle_rotatez xx 3 Make sure the draw_ground_first 1 to ensure that the main panorama overplays the ground After re starting Stellarium your landscape will appear in the landscape tab of the config uration window and can be selected as required APPENDIX E CREATING A PERSONALISED LANDSCAPE FOR STELLARIUM E 0 10 Making a Fisheye Panorama This sort of panorama needs a very expensive fisheye lens on your camera It is really only practical for a planetarium display to give a simple more or less silouette landscape where the ground is completely obscured It can normally only be used with quite small pictures of no more than 1024 x 1024 pixels Once you have your fisheye texture it must still be processed in TheGimp to r
151. s corrections Mac platform specifics Windows platform specifics Large parts of Appendix J Customisation of fab files Making a custom landscape Appendix E 0 4 and much work in updating the 2009 version to 2013 Japanese translation many corrections Colour magnitude diagram Many spelling corrections The rest of the Stellarium developer team Matthew Gates lt matthew porpoisehead net gt Paul Robinson Andras Mohari Rudy Gobits Dirk Schwarzhans Barry Gerdes Sigma The diagram is a modification of a diagram by Richard Powell who kindly granted permission for it to be distributed under the FDL John Twin You know who you are Additional material has been incorporated into the guide from sources that are pub lished under the GNU FDL including material from Wikipedia and the Astronomy book at Wikibooks 122 Bibliography 1 Douglas Adams The Hitchhiker s Guide to the Galaxy Pan Macmillan 1979 2 L H Aller I Appenzeller B Baschek H W Duerbeck T Herczeg E Lamla E Meyer Hofmeister T Schmidt Kaler M Scholz W Seggewiss W C Seitter and V Weidemann Landolt B rnstein Numerical Data and Functional Relationships in Science and Technology New Series 1989 3 Mark R Chartrand and Wil Tirion charts National Audubon Society Field Guide of the Night Sky Alfred A Knopf Inc 1991 4 Robert Dinwiddie lan Ridpath Pam Spence Giles Sparrow Carole Stott David Hughes Ke
152. s around the horizon Figure 5 3 Compass Marks When active this places a 360 degree scale around the horizon There is a tool bar button for toggling the compass markings or you can press control C Note that when you first enable compass marks the cardinal points will be turned off You can have both active at once but there is a small bug which means you have to press Q two times to re enable cardinal points after enabling the compass markings 5 13 PLUG INS CHAPTER 5 ADVANCED USE 0 Exoplanets A list of stars with planets around that can be displayed from an edit able data base exoplanets json Figure 5 4 Exoplanet locations When active this plug in reads the associated stars with exoplanets json file and places n the item with a name Exoplanets data is derived from The Extrasolar Planets Encyclopaedia Oculars This places a window on the screen that corresponds to the view through a telescope or on a camera It reads from an editable data base Antares a Sco 21 Sco HIP 80763 pulsatin Figure 5 5 Ocular window When this plug in is active a window will appear around the selected object depicting what would be seen by the viewing object On the top right hand side of the screen a menu will appear that can be used to select the viewing device eg Camera Eyepiece This menu is filled with items from the ocular ini file in the modules oculars folder This file can be edited from the Plugins me
153. seful when trying to find objects from star maps in the sky One way to do this with a device called a crossbow Crossbows are a nice way get an idea of angular distances but carrying one about is a little cumbersome A more convenient alternative is to hold up an object such as a pencil at arm s length If you know the length of the pencil d and the distance of it from your eye D you can calculate it s angular size O using this formula 7 An astronomical crossbow is essentially a stick with a ruler attached to the end The non ruler end of the stick is held up to the face and the user sights along the stick towards the object that is being observed The length of the stick is such that the markings on the ruler are a known angular distance apart e g 1 The markings on the ruler are often marked with luminescent paint for night time use has a nice illustration of the design and use of a crossbow The ruler is held in a curve by a piece of string giving a better indication of the reason for the name The curve is there to make all parts of the ruler perpendicular to the line of sight which improves the accuracy of the device 112 J 13 HANDY ANGLES APPENDIX J ASTRONOMICAL PHENOMENA d 0 2 arctan arctan 55 Another more handy ahem method is to use the size of your hand at arm s length Tip of little finger About 1 Middle three fingers About 4 Across the knuckles of the fist About 10 Open
154. splayed when an object is selected Navigation Figure 4 4 The Navigation and Tools tabs of the Configuration window The Navigation tab4 4 allows for enabling disabling of keyboard shortcuts for panning and zooming the main view and also how to specify what simulation time should be used when the program starts e When Syetem date and time is selected Stellarium will start with the simulation time equal to the operating system clock e When System date at is selected Stellarium will start with the same date as the operating system clock but the time will be fixed at the specified value This is a useful setting for those people who use Stellarium during the day to plan observing sessions for the upcoming evening e When Other is selected some fixed time can be chosen which will be used every time Stellarium starts 22 4 4 THE CONFIGURATION WINDOW CHAPTER 4 CONFIGURATION The Tools tab of the configuration window4 5 contains miscellaneous utility features Show flip buttons When enabled two buttons will be added to the main tool bar which allow the main view to be mirrored in the vertical and horizontal directions This is useful when observing through telecopes which may cause the image to be mirrored Spheric mirror distortion This option pre warps the main view such that it may be pro jected onto a spherical mirror using a projector The resulting image will be refected up from the spherical mirror
155. st was compiled by astronomers in the Northern Hemisphere it contains only objects from the north celestial pole to a celestial latitude of about 35 Many impressive Southern objects such as the Large and Small Magellanic Clouds are excluded from the list Because all of the Messier objects are visible with binoculars or small telescopes under favourable conditions they are popular viewing objects for ama teur astronomers In early spring astronomers sometimes gather for Messier Marathons when all of the objects can be viewed over a single night Stellarium includes images of many Messier objects 111 J 12 OBSERVING HINTS APPENDIX J ASTRONOMICAL PHENOMENA J 12 Observing Hints When star gazing there s a few little things which make a lot of difference and are worth taking into account Dark skies For many people getting away from light pollution isn t an easy thing At best it means a drive away from the towns and for many the only chance to see a sky without significant glow from street lighting is on vacation If you can t get away from the cities easily make the most of it when you are away Wrap up warm The best observing conditions are the same conditions that make for cold nights even in the summer time Observing is not a strenuous physical activity so you will feel the cold a lot more than if you were walking around Wear a lot of warm clothing don t sit lie on the floor at least use a camping mat co
156. system going under the name of ASCOM They provide an interface to stellarium and then translate the control into many other forms Multiple telescopes may be controlled simultaneously WARNING Stellarium will not prevent your telescope from being pointed at the Sun It is up to you to ensure proper filtering and safety measures are applied 48 5 13 PLUG INS CHAPTER 5 ADVANCED USE TextUserInterface TUI A way to change many parameters from the Stellarium Pro gram Figure 5 13 Text User Interface The text user interface is basically for the use in planetariums When the plug in is loaded it can be opened and closed with m This will pace the entry point on the lower left of the screen which may be obscured by the landscape To use it you scroll through the options with the arrow keys and press enter when the desired function is listed TimeZoneConfiguration Used to manipulate the time zone of the display Time zone Time zone Figure 5 14 Time Zone configuration screen This plugin is accessed from the plugins tab of the configuration menu The displayed time zone will default to the users time zone as stored in you computer s date tiime location settings This is not always suitable for displaying views from your home site The dis played timezone can be manipulated from the configure button 49 Appendix A Configuration file Section astro
157. t mouse wheel move_speed float all Sets the speed of movement zoom_speed float all Sets the zoom speed viewing _mode string all If set to horizon the viewing mode simulate an alt azi mount if set to equator the viewing mode simulates an equatorial mount flag_manual_zoom bool all Set to true if you want to auto zoom in incrementally auto_zoom_out_resets_direction bool all Set to true if you want to auto zoom restoring direction time_correction_algorithm strting all Algorithm of DeltaT correction Section plugins_load_at_startup Section ID Version Description AngleMeasure bool 0 10 3 If true Stellarium will be load Angle Measure plugin at startup Bright Novae bool 0 12 3 Tf true Stellarium will be load Bright Novae plugin at startup 59 APPENDIX A CONFIGURATION FILE continued Section ID Version Description CompassMarks bool 0 10 3 If true Stellarium will be load Compass Marks plugin at startup Exoplanets bool 0 11 4 If true Stellarium will be load Exoplanets plugin at startup Observability bool 0 11 4 Tf true Stellarium will be load Observability Analysis plugin at startup Oculars bool 0 10 3 If true Stellarium will be load Oculars plugin at startup Pulsars bool 0 11 2 If true Stellarium will be load
158. tars up to about 1 600 light years from the Earth after which the annual parallax is so small it cannot be measured accurately enough I 6 Proper Motion Proper motion is the change in the position of a star over time as a result of it s motion through space relative to the Sun It does not include the apparent shift in position of star due to annular parallax The star exhibiting the greatest proper motion is Barnard s Star which moves more then ten seconds of arc per year 100 Appendix J Astronomical Phenomena This chapter focuses on the observational side of astronomy what we see when we look at the sky J 1 The Sun Without a doubt the most prominent object in the sky is the Sun The Sun is so bright that when it is in the sky it s light is scattered by the atmosphere to such an extent that almost all other objects in the sky are rendered invisible The Sun is a star like many others but it is much closer to the Earth at approximately 150 million kilometres The next nearest star Proxima Centuri is approximately 260 000 times further away from us than the Sun The Sun is also known as Sol it s Latin name Over the course of a year the Sun appears to move round the celestial sphere in a great circle known as the ecliptic Stellarium can draw the ecliptic on the sky To toggle drawing of the ecliptic press the 4 or key WARNING Looking at the Sun can permanently damage the eye Never look at the Sun without using
159. the photo and place it on the clipboard Run TheSky and centre on the object centre Look in the Tools menu for the image link and select setup Tick show image frame to put a frame around the image Paste the clipboard image on the display and use the zoom and position controls to get it as close to the size and position as possible by visually matching stars Go to the menu again and click on link wizard If you have been successful the window will show the number of stars matched and the option to accept or continue Accept and you will now see all the matched stars have overlaid the picture You can now read off the corner coordinates from the status bar starting at the bottom south left and continuing counter clockwise to the top north left H 0 18 Processing into a Textures json Insert Place your image in the png format in the nebula default folder Ensure that the name matches the textures json entry 90 APPENDIX H ADDING EXTRA DEEP SKY PHOTOS TOR STELLARIUM Once you have the corner coordinates of your photo you can add them to the decimal converter program and it will write an insert nebula json as a text file that you can paste directly into the textures json file that is in the nebula default folder Save the textures json file with the new insert and run Stellarium Select the object in the Object selection window and slew to it Your image should be there and with a bit of luck it will nicely overlay the stars in the
160. the initial value of the bortle scale Typical value 3 Section tui Section ID Version Description flag_enable_tui_menu bool pre 0 9 1 Enables or disables the TUI menu 0 10 3 flag_show_gravity_ui bool pre 0 9 1 Enables or disables gravity mode for UI 0 10 3 flag_show_tui_datetime bool pre 0 9 1 Set to true if you want to see a date and 0 10 3 time label suited for dome projections flag_show_tui_short_obj_info bool pre 0 9 1 set to true if you want to see object info 0 10 3 suited for dome projections Section Video Section ID Version Description fullscreen Bool all If true Stellarium will start up in full screen mode If false Stellarium will start in windowed mode screen_w integer all Sets the display width in pixels when in Windowed mode Default 1024 screen_h integer all Sets the display height in pixels when in Windowed mode Default 768 screen_x integer all value in pixels deffault 0 horizontal_offset integer all value in pixels deffault 0 vertical _offset integer all value in pixels deffault 0 62 APPENDIX A CONFIGURATION FILE continued Section ID Version Description distorter string 0 8 0 This is used when the spheric mirror display 0 10 2 mode is activated Values include none and fisheye_to_spheric_mirror viewport_effect string 0 10 3 This is used when the spheric mirror display mode is activated
161. this grid or press the z key 1 2 2 Right Ascension Declination Coordinates Like the Altitude Azimuth system the Right Ascension Declination RA Dec coordinate system uses two angles to describe positions in the sky These angles are measured from standard points on the celestial sphere Right ascension and declination are to the celestial sphere what longitude and latitude are to terrestrial map makers The Northern celestial pole has a declination of 90 the celestial equator has a declin ation of and the Southern celestial pole has a declination of 90 Right ascension is measured as an angle round from a point in the sky known as the first point of Aries in the same way that longitude is measured around the Earth from Greenwich Figure T 2 illustrates RA Dec coordinates Unlike Altitude Azimuth coordinates RA Dec coordinates of a star do not change if the observer changes latitude and do not change over the course of the day due to the rotation of the Earth the story is complicated a little by precession and parallax see sections 1 4 and L 5 respectively for details RA Dec coordinates are frequently used in star catalogues such as the Hipparcos catalogue 94 1 3 UNITS APPENDIX I ASTRONOMICAL CONCEPTS Figure 1 3 Solar and Sidereal days Stellarium can draw grid lines for RA Dec coordinates Use the button on the main tool bar to activate this grid or press the e key 13 Units 13 1 Distance As Douglas
162. tion for some bodies widely regarded as being planets but which didn t seem to fit with the others In 2006 the International Astronomical Union defined a planet as a celestial body that within the Solar System a is in orbit around the Sun b has sufficient mass for its self gravity to overcome rigid body forces so that it assumes a hydrostatic equilibrium nearly round shape and Thousands of years ago Sirius was reported in many account to have a red tinge to it a good explanation for this has yet to be found 3A common aide to memory for the letters used in spectral types is the mnemonic Oh Be A Fine Girl Kiss Me 106 J 4 THE MAJOR PLANETS APPENDIX J ASTRONOMICAL PHENOMENA The moon s disc is fully in shadow or there New Moon is just a slither of illuminated surface on the edge Less than half the disc is illuminated but more is illuminated each night Approximately half the disc is illuminated and increasing each night More than half of the disc is illuminated and still increasing each night Full Moon The whole disc of the moon is illuminated More than half of the disc is illuminated but the amount gets smaller each night Approximately half the disc is illuminated but this gets less each night Less than half the disc of the moon is illu minated and this gets less each night Waxing Crescent First Quarter Waxing Gibbous Waning Gibbous Last Quarter
163. tion art 5 4 Constellation Boundaries Changes the colour of the constellation boundary lines 5 5 Cardinal Points Changes the colour of the cardinal point markers 5 6 Planet Names Changes the colour of the labels for planets 57 Planet Orbits Changes the colour of the orbital guide lines for plan ets 5 8 Planet Trails Changes the colour of the planet trail lines 5 9 Meridian Line Changes the colour of the meridian line 5 10 Azimuthal Grid Changes the colour of the lines and labels for the azi muthal grid 5 11 Equatorial Grid Changes the colour of the lines and labels for the equatorial grid 5 12 Equator Line Changes the colour of the equator line 5 13 Ecliptic Line Changes the colour of the ecliptic line 5 14 Nebula Names Changes the colour of the labels for nebulae 5 15 Nebula Circles Changes the colour of the circles used to denote the positions of nebulae only when enabled int he con figuration file note this feature is off by default 6 Effects menu group 6 1 Light Pollution Luminance Changes the intensity of the light pollution simulation 6 2 Landscape Used to select the landscape which Stellarium draws when ground drawing is enabled 6 3 Manual zoom Changes the behaviour of the and keys When set to No these keys zoom all the way to a level defined by object type auto zoom mode When set to Yes these keys zoom in and out a smaller amount and multiple presses are required 6 4 Object Sizing Rule When set
164. tion is valid from 1885 A D 2099 A D Earth s Moon ELP2000 82B Unsure about interval of validity or precision at time of writing Possibly valid from 1828 A D to 2047 A D Galilean satellites L2 Valid from 500 A D 3500 A D 65 Appendix C TUI Commands 1 Set Location menu group 1 1 Latitude Set the latitude of the observer in degrees 1 2 Longitude Set the longitude of the observer in degrees 1 3 Altitude m Set the altitude of the observer in meters 1 4 Solar System Body Select the solar system body on which the observer is 2 Set Time menu group 2 1 Sky Time Set the time and date for which Stellarium will gener ate the view 2 2 Set Time Zone Set the time zone Zones are split into continent or region and then by city or province 2 3 Days keys The setting Calendar makes the and keys change the date value by calendar days multiples of 24 hours The setting Sidereal changes these keys to change the date by sidereal days 2 4 Preset Sky Time Select the time which Stellarium starts with if the Sky Time At Start up setting is Preset Time 2 5 Sky Time At Start up The setting Actual Time sets Stellarium s time to the computer clock when Stellarium runs The setting Preset Time selects a time set in menu item Preset Sky Time 2 6 Time Display Format Change how Stellarium formats
165. tions orbit_MeanAnomoly float Object parameter used in comet_orbit calculations orbit_ArgOf Pericenter float Object parameter used in comet_orbit calculations Table 5 9 ssystem ini file format 41 5 11 OTHER CONFIGURATION FILES CHAPTER 5 ADVANCED USE An example entry might look like this ceres name Ceres parent Sun radius 470 oblateness 0 0 albedo 0 113 halo true color 1 0 1 0 1 0 tex_halo starl6x16 png coord_func comet_orbit orbit_TimeAtPericenter 2453194 01564059 orbit_PericenterDistance 2 54413510097202 orbit_Epoch 2453800 5 orbit_MeanAnomaly 129 98342 orbit_SemiMajorAxis 2 7653949 orbit_Eccentricity 0 0800102 orbit_ArgOfPericenter 73 23162 orbit_AscendingNode 80 40970 orbit_Inclination 10 58687 lighting true sidereal_period 1680 15 5 11 Other Configuration Files In addition to the files discussed in the previous sections Stellarium uses various other data files Many of these files may be edited easily to change Stellarium s behaviour See table 5 11 4Not all files in the to want to modify 42 data directory are listed here only the ones which the advanced user is most likely 5 12 TAKING SCREENSHOTS CHAPTER 5 ADVANCED USE File Purpose data base_locations txt Each line is one record which describes a location which will appear on the map in the location dialog A charact
166. tis 1 amp 2 Double Star 5 02 5 02 Follow a line from Seginus to Nekkar and then continue for the same distance again to arrive at this double star This pair are of different spectral type and 52 Bootis at approximately 800 light years is twice as far away as 53 116 Appendix L Exercises L 1 Find M31 in Binoculars M31 the Andromeda Galaxy is the most distant object visible to the naked eye Finding it in binoculars is a rewarding experience for new comers to observing L 1 1 Simulation 1 Set the location to a mid Northern latitude if necessary M31 isn t always visible for Southern hemisphere observers The UK is ideal 2 Find M31 and set the time so that the sky is dark enough to see it The best time of year for this at Northern latitudes is Autumn Winter although there should be a chance to see it at some time of night throughout the year 3 Set the field of view to 6 or the field of view of your binoculars if they re different 6 is typical for 7x50 bins 4 Practise finding M31 from the bright stars in Cassiopeia and the constellation of Andromeda L 1 2 For Real This part is not going to be possible for many people First you need a good night and a dark sky In urban areas with a lot of light pollution it s going to be very hard to see Andromeda L 2 Handy Angles As described in section J 13 your hand at arm s length provides a few useful estimates for
167. titude float 0 6 2 Observer s altitude above mean sea level 0 9 1 in meters e g 53 landscape_name string all sets the landscape you see Other options are garching guereins trees moon ocean hurricane hogerielen time_zone string 0 6 2 Sets the time zonetime zone Valid 0 9 1 values system_default or some region location combination e g Pacific Marquesas time_display_format string 0 6 2 Set the time display formattime display 0 9 1 format mode can be system_default 24h or 12h date_display_format string 0 6 2 Set the date display format mode can be 0 9 1 system_default mddyyyy ddmmyyyy or yyyymmdd ISO8601 home_planet string 0 6 2 Name of solar system body on which to 0 9 1 start stellarium This may be set at runtime from the TUI menu location string 0 10 1 Name of location on which to start stell 57 APPENDIX A CONFIGURATION FILE Section landscape Section ID Version Description flag_landscape bool all Set to false if you don t want to see the landscape at all flag_fog bool all Set to false if you don t want to see fog on start up flag_atmosphere bool all Set to false if you don t want to see fog on start up flag_landscape_sets_location bool all Set to true if you want Stellarium to modify the observer location when a new landscape is selected changes planet and longitude latitude altitude if that
168. to 3 4 and back W of Cassiopeia within a matter of hours The reason for this change is that Algol has a dimmer gi ant companion star with an orbital period of about 2 8 days that causes a regular par tial eclipse Although Algol s fluctuations in magnitude have been known since at least the 17th century it was the first to be proved to be due to an eclipsing compan ion it is therefore the prototype Eclipsing Variable Sirius Alpha Canis Majoris Star 1 47 Sirius is easily found by following Sirius is a white dwarf star at a comparat the line of three stars in Orion s belt ively close 8 6 light years This proximity southwards and it s high innate luminance makes it the brightest star in our sky Sirius is a double star it s companion is much dimmer but very hot and is believed to be smaller than the earth M44 The Beehive Open Cluster 37 Cancer lies about halfway between There are probably 350 or so stars in this Praesepe the twins Castor amp Pollux in cluster although it appears to the naked eye Gemini and Regulus the brightest simply as a misty patch It contains a mix star in Leo The Beehive can be ture of stars from red giants to white dwarf found between Asellus Borealis and and is estimated to be some 700 million Asellus Australis years old 27 Cephei Delta Cephei Variable Star 4 0 Avg Locate the four stars that form the Delta Cephei gives it s name to a whole square of Cepheus One corner of t
169. to the Sun the heat evaporates the ices causing a gaseous release This gas and loose material which comes away from the body of the comet is swept away from the Sun by the Solar wind forming the tail Comets whose orbit brings them close to the Sun more frequently than every 200 years are considered to be short period comets the most famous of which is probably Comet Halley named after the British astronomer Edmund Halley which has an orbital period of roughly 76 years J 6 Galaxies Stars it seems are gregarious they like to live together in groups These groups are called galaxies The number of stars in a typical galaxy is literally astronomical many billions sometimes ever hundreds of billions of stars 108 J 7 THE MILKY WAY APPENDIX J ASTRONOMICAL PHENOMENA Our own star the sun is part of a galaxy When we look up at the night sky all the stars we can see are in the same galaxy We call our own galaxy the Milky Way or sometimes simply the Galaxy Other galaxies appear in the sky as dim fuzzy blobs Only four are normally visible to the naked eye The Andromeda galaxy M31 visible in the Northern hemisphere the two Magellanic clouds visible in the Southern hemisphere and the home galaxy Milky Way visible in parts from north and south under dark skies There are thought to be billions of galaxies in the universe comprised of an unimagin ably large number of stars The vast majority of galaxies are so
170. use cursor over the buttons a short description of the button s purpose and keyboard shortcut will appear Button Shortcut key Description j Decrease the rate at which time passes k Make time pass as normal Increase the rate at which time passes 4 72 8 Return to the current time amp date Table 3 2 Time control tool bar buttons OK so lets go see the future Click the mouse once on the increase time speed button Not a whole lot seems to happen However take a look at the clock in the status bar You should see the time going by faster than a normal clock Click the button a second time Now the time is going by faster than before If it s night time you might also notice that the stars have started to move slightly across the sky If it s daytime you might be able to see the sun moving but it s less apparent than the movement of the stars Increase the rate at which time passes again by clicking on the button a third time Now time is really flying Let time move on at this fast speed for a little while Notice how the stars move across the sky If you wait a little while you ll see the Sun rising and setting It s a bit like a time lapse movie Stellarium not only allows for moving forward through time you can go backwards too Click on the real time speed button The stars and or the Sun should stop scooting across the sky Now press the decrease time speed button
171. ves down towards the horizon At the Earth s equator the North celestial pole appears to be on the Northern horizon 92 12 COORDINATE SYSTEMS APPENDIX I ASTRONOMICAL CONCEPTS zenith altitude nadir Figure I 1 Altitude amp Azimuth Similarly observers in the Southern hemisphere see the Southern celestial pole at the zenith when they are at the South pole and it moves to the horizon as the observer travels towards the equator 1 Leave time moving on nice and fast and open the configuration window Go to the location tab and click on the map right at the top i e set your location to the North pole See how the stars rotate around a point right at the top of the screen With the field of view set to 90 and the horizon at the bottom of the screen the top of the screen is the zenith 2 Now click on the map again this time a little further South You should see the positions of the stars jump and the centre of rotation has moved a little further down the screen 3 Click on the map even further towards and equator You should see the centre of rotation have moved down again To help with the visualisation of the celestial sphere turn on the equatorial grid by clicking the button on the main tool bar or pressing the on the e key Now you can see grid lines drawn on the sky These lines are like lines of longitude and latitude on the Earth but drawn for the celestial sphere The Celestial Equator is the line ar
172. vin Tildsley Philip Eales and Iain Nicolson Universe Dorling Kindersley 2005 5 Various Wikibooks Astronomy Wikimedia Foundation 123 Index Algol variables 101 cluster 87 Altitude comet altitude Comet Halley 108 altitude angle common name es Eg common names angles 96 config ini 29 annual parallax 98 configuration file apparent magnitude 67 103 constellation 13 arc minutes Andromeda 117 arc second Aquarius arc seconds 96 Canis Major asterism Cassiopeia asteroid diagram 102 asteroids 108 Orion 103 astro photography Ursa Major astrometry 101 constellation art astronomical unit constellation lines 67 atmospheric effects constellations fog coordinate system AU 95 crossbow 112 auto zoom 67 customising auto zoom landscapes axis of rotation cylinder projection azimuth cylindrical equidistant projection angle azimuth PES date azimuthal equidistant projection Dec 94 azimuthal grid declination dwarf planet Barnard s Star 100 dwarf stars Bayer Johan 103 binaries TOT Earth 65 96 98 107 binoculars orbit boundary lines rotation brightness 96 rotation of 92 brown dwarfs 104 Earth Moon barycenter 65 eccentric 108 cardinal points eclipse 6 catalogue 69 eclipsing binaries celestial equator ecliptic celestial pole 92 92 94 ecliptic line celestial sphere 69 elliptical
173. w is 150 The mathematical name for this projection method is gnomonic projection stereographic This mode is similar to fish eye projection mode The maximum field of view in this mode is 235 4 5 3 Landscape Tab The Landscape tal 4 7 of the View window controls the landscape graphics ground To change the landscape graphics select a landscape from the list on the left side of the win dow A description of the ladscape will be shown on the right Note that while landscape can include information about where the landscape graphics were taken planet longitude latitude and altitude this location does not have to be the same as the location selected in the Location window although you can set up Stellarium such that selection of a new landscape will alter the location for you The controls at the bottom right of the window operate as follows 25 4 5 THE VIEW SETTINGS WINDOW CHAPTER 4 CONFIGURATION Figure 4 7 The Landscape tab of the View window Show ground This turns on and off landscape rendering same as the button in the main tool bar Show_fog This turns on and off rendering of a band of fog haze along the horizon Use associated planet and position When enabled selecting a new landscape will auto matically update the observer location Use this landscape as default Selecting this option will save the landscape into the pro gram configuration file so that the current landscape will be the one used when
174. with information about the server imageCredits a structure containing the same parts as a serverCredits structure but referring to the image data itself shortName an identifier for the set of images to be used inside Stellarium minResolution minimum resolution applies to all images in the set unless otherwise specified at the image level maxBrightness the maximum brightness of an image applies to all images in the set unless otherwise specified at the image level subTiles a list of structures describing indiviual image tiles or referring to an other json file Each subTile may contain minResolution maxBrightness worldCoords subTiles imageCredits imageUrl textureCoords shortName name for the whole set of images e g Nebulae miniResolution applies to all images in set alphaBlend applies to all images in set subTiles list of images Each image record has the following properties imageCredits itself a list of key pairs imageUrl e g file name worldCoords a list of four pairs of coordinates representing the corners of the image 38 5 9 SKY CULTURES CHAPTER 5 ADVANCED USE Table 5 6 Sky culture configuration files textureCoords a list of four pairs of corner descriptions i e which is top left of image etc minResolution over rides file level setting maxBrightness Items enclosed in Quotation marks are strings for use in the prog
175. y gt landscapes or lt installation directory gt landscapes The name of the sub directory is called the landscape ID The sub directory must contain a file called landscape ini which describes the landscape type texture filenames and other data Texture files for a landscape should by put in the same directory as the landscape ini file although if they are not found there they will be searched for in the textures directory allowing shared files for common textures such as the fog texture For example the Moon landscape that is provided with Stellarium has the following files gt landscapes moon landscape ini landscapes moon apollol7 png as The landscsape ini file must contain a section called landscape which con tains the details necessary to render the landscape which vary depending on the type of the landscape There is also an optional location section which is used to tell Stellarium where the landscape is in the solar system If the location section exists Stellarium can automatically adjust the location of the observer to match the landscape 5 7 1 Single Fish eye Method The Trees landscape that is provided with Stellarium is an example of the single fish eye method and provides a good illustration The centre of the image is the spot directly above the observer the zenith The point below the observer the nadir becomes a circle that just touches the edges of the image The remaining areas of the ima

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