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2 Installing Guide 2: 2 Getting Help 3: 3 What Guide is

1. type sc3 f6 32 0 32 0 16 26 16 26 16 26 16 26 c2 E0 0 15 c14 The three triangles are drawn as one six point fill that s the f6 part Then the color is set to 2 orange and a dot is drawn Finally the color is reset to 14 light gray for the label The align keyword is the sum of a number for the horizontal alignment 0 for left 1 for center 2 for right and a number for the vertical alignment 0 for top 16 for center 32 for bottom By default the alignment is zero and text is shown to the upper left of an object 20b Providing limits in RA and declination By default Guide will assume that your dataset covers the entire sky and will always examine it to see if any objects fall on the screen But if the dataset covers only part of the sky and Guide is aware of that fact it can sometimes avoid drawing the dataset at all This can produce a substantial improvement in speed For example if you look at RADIO TDF you ll see that the 6C Radio Sources II dataset has the following fields in it declimit 30 51 This catalog extends from N 30 to N 51 ralimit 8 5 17 5 This catalog extends from 8h30m to 17h30m in RA It just so happens that this particular dataset covers a particular 69 rectangle in RA dec Since Guide knows this it can often compare that rectangle to the one on the screen find that there is no overlap and deduce that there is no point in even considering this data
2. Guide can show several planets and natural satellites using different maps For the Moon one of these maps bitmap 3 in the Planet Display dialog is only available from the second Guide CD It was created from Clementine imagery and has a resolution of a little better than a kilometer making it far more detailed than any other available image If you ve set Guide up to access the second Guide CD then the bitmap 3 option in the Planet Display dialog for the Moon will no longer by grayed out Select it and Guide will switch to that bitmap Zoom in on the Moon and you will see far more detail than was previously the case The only downside here is that the imagery was taken at local noon Features at middle to high latitudes look quite good but those at central latitudes tend to look washed out Also provided on the second disk are Extra asteroid elements The first disk contains elements that allow Guide to show asteroids with good accuracy over the years 1996 to 2004 Add in the extra elements from the first disk and this grows to 1960 to 2023 Some additional user added datasets such asthe CCDM Catalogue of Components of Double amp Multiple Stars the LEDA catalog of over one million galaxies _far_ more galaxies than are generally going to be visible to anyone you may choose to stick to Guide s default galaxy display additional star information from the Michigan Henry Draper catalogues shown when you cl
3. and if the currently selected camera has a guiding chip range rings will be added to the display to indicate the area the guiding chip could cover If you want to rotate the CCD to a particular point you can then right click on that part of either the inner or outer range ring You ll then see an option to Rotate CCD Click on that and the CCD will rotate to that point There is also a special way to move the frame to a new position put the cursor where you want the frame to be hold down the Ctrl key and click on the right mouse button This will turn the frame on if it s not already on and re draw it centered on the cursor Doing the same thing with the Shift key will rotate the frame so that it points toward the place where you clicked 7e The Legend Menu The Legend menu in the Display menu controls what is shown in the area at the lower left corner of the chart This legend is also shown on the printed chart You can reach the Legend menu either by clicking on the Legend item in the Display menu or by hitting Ctrl L It looks like this Show Legend Show Time Time Zone Lat Lon Caption RA Dec Field Size Object key Mag Key 24 Compass Sky Atlas 2000 Uranometria New Uranometria Millennium Alt Az Ecliptic coords Galactic coords Supergalactic coords Hour Angle Second Time Add to caption Clear Caption Layout Positron x Vertical x Bottom Horizontal Top x Left Right Center Opti
4. between where you clicked and where the mouse is When you release the right mouse button the distance and position angle between the two points will show up in a box in the center of the screen Click any mouse button or hit any key to get rid of the box The position angle is the angle formed by the line you drew and a line running straight north from the first point The term is commonly used to describe how a pair of double stars is oriented how the long axis of a galaxy is oriented and so forth The exact distance and position angle between two _objects_ may be obtained in a different way Right click on the first object the information box described inthepreceding chapter will appear Click OK and repeat the process with the second object Now hit Insert Guide will now compute exact data between the two objects and measuring errors are avoided In general just dragging aline between two points will work well enough but there are cases where you may want atruly precise value 6b Quick Info For some general purpose information one wants easy access The Quick Info option in the Help menu lists much of this sort of data like planetary positions times of lunar phases current local and Greenwich sidereal times comets brighter than magnitude 15 asteroids 15 brighter than magnitude 11 the current equation of time and the currently set date in various calendars Hebrew Islamic French Revolutionary and so forth I
5. options are extensions of the data shown in Quick Info Quick Info always shows currently visible asteroids down to magnitude 11 and comets to mag 15 In the Tables Menu you can set a different limiting magnitude and get a little more control over how much data you receive List Planet Features will result in a list of all features on whichever planet s are currently in the field of view and which are also large enough to show disks at the current zoom level In these respects the list will resemble that seen for the Go to Planet Feature option see page 7 List Satellite passes can be used to get a table of visible passes for a given satellite or a table for many or all satellites It brings up a dialog box in which you can specify a satellite name Enter for example ISS and passes of the International Space Station would be found Enter and it is interpreted as a wild card passes of _all_ satellites will be tabulated Between these extremes you could enter Landsat to get passes of all the Landsat related satellites You then can specify the number of days to be covered starting from the currently set time in Guide and there s a check box to tell Guide to show only visible passes that is ones in which the satellite gets brighter than a certain magnitude gets higher than a certain altitude above the horizon and does so with the sun at least a certain altitude below the horizon You can set those certai
6. production of the Guide Star Catalog are described in Volume 99 pp 2019 2154 ofthe Astronomical Journal and intext files on the CD ROM version of the GSC from which data contained herein were extracted Those text files are also on this CD in the TABLES subdirectory The PGC Principal Galaxy Catalog was obtained from the Universite de Lyon Itwas compiled byG Paturel and L Bottinelli of the Observatoire de Paris and forms the basis for displaying galaxies at detailed levels The RC3 Third Revised Catalog of Galaxies was obtained from Dr 74 Harold Corwin at the California Institute of Technology It was compiled by G and A de Vaucouleurs H G Corwin R J Buta G Paturel and P Fouque With the PGC itis largely responsible for the great improvements in the accuracy and quantity of data provided for galaxies The primary source for data on NGC and IC objects comes from Wolfgang Steinicke s list onthe NGC IC Project Web site www ngcic org used by permission here Comments on many NGC and IC objects were supplied by Steve Coe who kindly gave permission for extracts from his observing notes to be shown in more info Additional NGC andICdatacomes from the Saguaro Astronomy Club The members ofthis club did anenormous amount of work incleaning up many errors inthe RNGC and NGC2000 catalogs inthe course of producing this work and I am very happy to be able to make use of the results Nebula catalogs have long been a
7. symbols To do this you need to alter the type line in a TDF An example is type scl5 e0 0 32 cl1 E 20 20 12 3 10 5 10 5 0 10 c2 m 45 0 145 0 c14 The s stands for symbol and tells Guide you aren t using the usual pre defined symbol types Following are commands separated by semicolons 68 eLo means set color 15 white e0 0 32 means draw a 32 unit circle centered at 0 0 Gils means set color 1 green E 20 20 12 means draw a 12 unit _filled_ circle at 20 20 3 10 15 30 15 20 30 means draw a 3 point _filled_ object a triangle connecting 10 15 to 30 15 to 20 30 C2 means set color 2 brown m 45 0 means move to 45 0 145 0 means draw a line connecting to 45 0 c14 means set color 14 light gray The symbols are scaled just like the standard predefined types large objects are drawn with scaled up symbols just as large for example globular clusters are drawn with larger circles The unit of measurement in the above commands is 1 32 of an object radius For example the 32 unit circle drawn above would exactly match the size of the object By setting the color to light gray at the end we make sure that the label for this object is in light gray Here s amore practical example Suppose you want to show a catalog of gamma ray burst events with radiation symbols three triangles in light blue with orange dots in the center
8. 10 71h 41 41 24 104236 0 414124 all refer to the same position in the sky and all will be correctly understood by Guide You can leave out minutes or seconds put spaces between fields use in place of N S and use decimal amounts If Guide can t figure out what you meant it will tell you so with an error message and will give you a chance to try again You can also indicate if the RA dec you are entering is in the J2000 B1950 mean apparent or other epoch Most of the time you will probably be entering J2000 coordinates Some older data is given in B1950 and in rare cases you may need to enter coordinates in one of the other epochs The concept of an epoch is explained in the Appendices page 76 Note that this allows you to set the epoch of the coordinates you re entering but doesn t change the epoch used for RA dec coordinates displayed by Guide If it s the latter you want to change you should use the Formats dialog described on page 31 6 GETTING INFORMATION ABOUT OBJECTS What Guide shows you on the chart is a fraction of what it knows about the objects in the chart Since Guide can t show everything at once you get extra data about most objects by clicking on them with the right mouse button This gives you a quick summary of important data about the object its name catalog number s rise set times and so forth You can then ask for more info about the object including everything Guide kn
9. OK Cancel The Full Precision and Label by Name options are identical to those accessed through the Data Shown dialog and are discussed on page 21 They affect all planets But the remaining options will affect only the currently selected planet Mars in the above example For Mars and some other planets along list of features craters volcanoes markings is available Set the Show Features option and they will be marked add Label features and they will be named You can select colors both for the features themselves and their labels and set the density of features a larger number causes more features to appear When features are shown you can right click on them to get information about them This isespecially useful with the Moon which has thousands of named craters You can also add a lat lon grid of specified spacing and color In the case of Mars you can select among three bitmaps Two are based on visual observations one is based on Viking data Few objects have three bitmaps Venus has two one shows it as a 22 cloud covered planet the other as it appeared to the radar mapping Magellan probe If your viewing location is not on the earth you can look back at the earth and see it with any of three different bitmaps Most planets have one bitmap or none The Moon has an extremely detailed bitmap Unfortunately it is about 90 MBytes and had to be put on the second CD ROM For details on how t
10. appears in both Tycho Hipparcos and in the GSC it will have data from both catalogs Sometimes this is useful which is why the second line is not removed but in most cases one will want to pay attention to the Tycho data and ignore the GSC data Ifa GSC star appears on more than one plate in the GSC it will appear more than once inthe list Multiple appearances are common since the plates overlap quite a bit The Miscellaneous Tables option originally just listed a few tables of interesting but not easily categorized events Clicking on it now brings up a long list of tables of events such as planetary occultations transits of Mercury and Venus dates of meteor showers and more If text appears red in the table it refers to an event that occurs below your horizon If the text is yellow the event is less than ten degrees above the horizon visible but not by much If it s in green the event is more than ten degrees above the horizon You can click on any such colored text to cause Guide to recenter on the object event in question 17 THE EXTRAS MENU The Extras menu offers the following options DSS RealSky Images 52 Get Star Catalog data Asteroid options Fixed levels Toggle user datasets Make PostScript file Make BMP File Find conjunction Show eclipse Install to hard drive The DSS RealSky Images option leads to a dialog box in which images from the Digital Sky Survey and RealSky dataset
11. at the center of the screen as you pan around instead of staying fixed relative to the sky Changing the Angle value lets you set the tilt of the frame to any desired angle The Spin Left and Spin Right options each cause the frame to rotate a few degrees and may be more helpful You can then select the focal length of your telescope and the identity of your CCD camera A few points you can switch between 23 a focal length in millimeters and one in inches by using the Units section of the Format dialog box described on page 31 Certain film format sizes including the ever popular 35mm frame are given in the list As you change these parameters Guide will update data on the angular dimensions of the frame and pixels If you choose an SBIG or similar camera with a guiding chip then the guider chip will be shown at the proper scale and position If your camera doesn t appear in the list shown by Guide you should first check the Project Pluto Web site for updates to the software If the camera is still not listed please contact Project Pluto it does happen that new cameras escape our notice until someone mentions that they aren t listed Set the show pixels check box and the grid of pixels will be shown overlaid on the CCD frame Ifthe binning option is set to something other than 1x1 then the binned pixels will be shown that is the grid will be made sparser Set the guider range check box
12. be adifficult undertaking e g the GSC Tycho and PPM data The compression really is not intended to frustrate people But a quick check will show you that the CD ROMs are almost completely full unless many larger datasets were highly compressed something would havebeen omitted Because of the concern about fitting everything on the CDs a lot of effort went into compressing the larger datasets Little was usually done to smaller datasets since compressing them would not have helped very much anyway Full details on accessing the datasets are available at http www projectpluto com access htm This is updated from time to time some datasets are currently undocumented simply because no one asked about them If you have a particular dataset you d like to access please contact Project Pluto 24 ACKNOWLEDGMENTS Much of the data for this CD came through the Centre des Donnees Astronomiques de Strasbourg http cdsweb u strasbg fr The Hipparcos and Tycho data were created by the European Space Agency and are used here by permission The source for faint stars is the Hubble Guide Star Catalog distributed by the Space Telescope Science Institute This dataset was originally intended to support precise pointing of the Hubble Space Telescope The Guide Star Catalog GSC is copyrighted by the Association of Universities for Research in Astronomy AURA and is reproduced here by permission The scientific efforts leading to the
13. click on those coordinates and Guide will prompt you to enter new coordinates For example if the RA dec is shown in the legend you can click on it and Guide will ask for a new RA dec If the altitude azimuth is shown you can click on that and Guide will ask for an alt az position and so on for the other coordinate systems Also you can select any of these coordinate systems from the Coordinates menu under the Go To menu The Coordinates menu 12 also has an Opposition Point option to find the point directly opposite the sun When entering an alt az position you will be asked to enter the altitude first This can range from 90 straight down the nadir to zero a point on the horizon to 90 straight up the zenith Next you will be asked to enter an azimuth or bearing This can range from zero due north to 90 due east to 180 south to 270 west to 360 north again Guide will then recenter on the position given A description of alt az is given in the Appendices on page 78 If the coordinates aren t being shown in the legend or if you want other coordinates such as ecliptic or galactic to appear in the legend you can toggle them on quite easily This is described on page 24 A comment on entering RA dec positions Guide is quite willing to accept the many forms of RA dec coordinates for example 10h42m36 00s N41 69 10h 42m 36s N41 41 24 10 42 36 41 41 24 10h 42 6m N41 41 6
14. distorted This isn t such a big deal for charts of the earth where people are not too concerned about the poles But people look at the celestial poles all the time The Mercator projection preserves shapes But areas are greatly magnified near the poles The Peters projection has the reverse problem areas are preserved accurately but shapes are compressed or stretched The Miller projection and simple projections arecompromises neither preserving shape or area but not distorting area as badly as Mercator or shape as badly as Peters The Toolbar dialog shows a list of all functions that can appear on the toolbar You can highlight arange of them using the mouse and then select On or Off to turn all highlighted items on or off You can also just double click an option to toggle it You can use the Show Toolbar checkbox to suppress display of the toolbar and you can click OK to confirm your changes or Cancel to reject them By default Guide shows a reasonable sample of functions on the toolbar Buttons are provided for the most commonly used zoom levels 1 4 7 and 10 Buttons are provided to print to go to a planet to find a point on the horizon to go into the Time Menu to go toa full horizon view 180 degrees wide centered at the zenith to use the data shown dialog page 19 and to use the Animation dialog page 46 Probably almost everyone will have a different set of most commonly used functions and therefor
15. essential If you ve provided line size and nlines _and_ the data is sorted in order of increasing RA then it s a good idea to add the sort 1 keyword If Guide knows the dataset is already sorted it can skip over large amounts of data and draw your dataset _much_ faster Fortunately many datasets are provided in this order and or are small enough to make this improvement less important Also you ll need to provide a type keyword to tell Guide how to display the object The pre defined values for type are radiation symbol for X ray or gamma ray sources radio dish already used for all catalogs in RADIO TDF 0 open clus 1 globular 2 diffuse neb 3 planetary nebula 4 galaxy 5 OC amp neb 6 star 7 circle ellipse 8 9 For all types except 6 star the symbol size will be scaled by the sizs or sizm or sizd data Stars are sized by the mag data For type 7 if a siz2 field is supplied it specifies one usually minor axis of an ellipse with the size field supplying the other usually major axis If no siz2 is supplied you just get a circle of the specified size If both a siz2 and a pa position angle field are given then the ellipse is tilted at that angle Take alook atthe UCAS Galaxies inCD_DATA2 TDF for anexample of how this works 20a Defining your own custom TDF symbols Using a pre defined type is easy But you can also create your own
16. has generated a precise value and that any difference must be due to errors in Guide It may be flatly stated that properly used Guide will indeed generate data to the precisions listed in the next section APPENDIX E NOTES ON ACCURACY The subject of the accuracy of any astronomy software is a very complex one The accuracy of positions shown by Guide varies from about a thousandth of an arcsecond for stars in the Hipparcos catalog to being as poor as several degrees for some asteroids whose orbits have not been thoroughly studied or artificial satellites that have maneuvered or haven t been updated recently For moving objects the accuracy is also a function of time that of positions of planets within a century of the year 2000 is of the order of milliarcseconds but probably no better than arcminutes for very 79 distant dates There is a very thorough description of accuracy in the files TEXTACCURACY HTM HTML version TEXTACCURACY TXT text version http www projectpluto com accuracy htm These describe what level of accuracy can be expected for various data in Guide how that level was determined and what factors can affect that level of accuracy If your sole need is to be able to find objects visually or telescopically then the accuracy given by Guide will always be far more than sufficient APPENDIX F ADDING NEW COMETS Guide is shipped with a fairly complete list of comets and with a set of over 158 000 a
17. long In 1984 the International Astronomical Union decided to switch to the start of Julian years which are exactly 365 25 days long The actual difference in the sky is always well under 1 second of arc and you can usually ignore these prefixes with very little harm With the exception of Hipparcos and Tycho stars and of planets and natural satellites in full precision mode no object in Guide can claim positional precision of 1 second or better APPENDIX C ALTITUDE AND AZIMUTH EXPLAINED You will note that all objects when clicked on show times of rising and setting plus their alt and azim This refers to the object s altitude and azimuth which tell you where in the sky to look for an object Altitude and azimuth are not reckoned from either the Earth s poles or the celestial poles They are reckoned from the observer s position the point straight overhead has an altitude of 90 degrees that straight underneath an altitude of 90 degrees Points on the horizon have 0 degree altitudes An object halfway up in the sky has an altitude of 45 degrees Thus looking at altitude tells you immediately if the object is even visible A negative altitude means the object is below the horizon A positive altitude less than say 10 degrees may make the object so close to the horizon that trees or buildings or smog may make it invisible Altitude gives you the how far from the horizon you use azimuth to determine wh
18. only for alignment of JMI MG III Tangent Instrument compatible systems and will be discussed in the next chapter For all other systems Guide just relies on the internal alignment of the telescope so be sure your scope is properly aligned in the manner described in its user manual The hardware issues in connecting a telescope to a computer are quite varied you should check the instruction manual for your telescope for details You should determine to which COM port the telescope is attached and pick the corresponding port in the dialog box If you don t know which port is used it s okay to guess The worst that will happen is that when you try to control the scope Guide will pause for about fifteen seconds then report its failure In general you can just pick the sort of telescope you re using select the right COM port and you ll be all set Most telescopes will either be in the above list or will use the Meade LX 200 command language so you can just tell Guide to use that system ASCOM is a system that allows a wide range of telescopes to be controlled including those in the above list plus many others If you select ASCOM you ll be asked to select your telescope from a different much larger list of 39 possibilities Once you have used the Telescope dialog to tell Guide what sort of telescope you have and which serial port it uses a Scope Pad item will be added to the main menu Clicking on Scope Pad
19. options to change levels as well as described on page 4 The Language submenu lists at present twelve languages English French German Spanish Italian Dutch Japanese Czech Russian Chinese Hungarian and Polish Click on one and Guide will switch to that language In some cases the translation is not yet complete Much text has been translated but some remains You may find updated versions and additional languages on the Web site from time to time The software allows for the easy addition of further languages If you re interested in adding your own language please let me know The Margins menu is described on page 43 Clicking on the Formats option brings up a dialog box that provides almost complete control over how coordinates and certain other data are shown in Guide Choose among hours degrees decimal minutes or decimal seconds for RA dec decide if leading zeroes should be 31 shown in positions and if declinations should begin with or N S Also you select the epoch in which positions are to be shown In this Format dialog one also controls how latitude longitude values are shown and switches between metric and traditional units inches miles etc There s also an option to reset the time date format so that you can have dates displayed year first or with two digit years or in Julian Day format and soon The choices you make here will be used throughout Guide The TLE option l
20. or IC 433 or Neptune It can also locate stars such as gam Per 61 Cyg Z Cam SAO 123456 or Betelgeuse asteroids such as Vesta or 1992 QBI1 and artificial satellites such as ISS or WIRE and many object names not specified here If in doubt about an object name just try entering it At worst Guide will respond with Object not found Unfortunately it can t decipher all possible object designations and some are ambiguous for example Io is both a satellite and an asteroid Mu Cep refers to two different stars depending on if Mu is aGreek letter or the variable star designation MU and so on So the following options are very useful To find a Messier NGC or IC object click on one of these three menu items and enter the catalog number Guide will recenter on that object The Horizon Menu brings up asmall dialog box listing eight compass points on the horizon plus the zenith point directly overhead and nadir point directly below you Click on one of these ten buttons and Guide will center the chart on that point The Satellite option will prompt you to enter the name of an artificial satellite Do so and Guide will recenter on that satellite 6 See page 32 for some important warnings about which satellites Guide knows about and how accurate its information is You can find a planet or the Sun or Moon or other natural satellite with the Planet option This gives a list of all plan
21. point in the sky to its alignment database After you have added at least two alignment stars you can actually getsome pointing feedback from thetelescope Click on Slew Telescope Guide will read the encoders atone second intervals putting ared circle on the screen to indicate where the scope is pointed If the scope is pointed off screen Guide will force aredraw and then put the red circle on the screen This is useful in aiming the telescope you set a wide field of view click Slew Telescope and push the telescope until the indicator circles the target Once you re done with this clicking on Slew Telescope again will shut off the red circle updates Alternatively clicking on Slew Guide will cause it to read the encoders once resulting in the chart being redrawn at the current telescope position Adding still more alignment stars can improve pointing accuracy considerably If you find that the accuracy is poor in a given part of the sky it s advisable to find a nearby bright star and to add it as another alignment star This gives Guide an idea as to the amount of error in that part of the sky it can then compensate accordingly At present there is no command to delete the alignment data and this is something you ll want to do if you move the scope or shut down the encoders Toclear alignment data delete the file ALIGN DAT inthe Guide directory 12 PRINTER SETUP AND PRINTING The Printer Setup menu isin the Fil
22. the acknowledgments and used in a short story Transit of Earth by Arthur C Clarke Had you been on Mars with a filtered telescope you would have seen a small black disk crossing the sun with a disk a quarter that size the Moon trailing behind It does illustrate how big the Sun really is The Jul 91 Mexico eclipse shows the total solar eclipse of July 11 1991 asseen from Mexico City The May 94 annular eclipse shows the less dramatic annular doughnut shaped solar eclipse that was visible from Project Pluto s corporate headquarters In this case the moon wasn t large enough to block out the sun and aring of sun was visible around the moon The Initial position mark file is used when the program starts up and ensures that you resume where you were when you last ran Guide with whatever settings you had at the time If you happen to get your settings thoroughly confused you can select this mark file to restore things to the way they were when you started the program If this does not restore things properly you can use the Factory default settings mark which puts everything back the way it was when Guide was installed You can save amark by hitting Save a Mark You will be asked to type amark name which must be less than 20 letters You can also delete an existing mark file with the Delete Mark option This option will bring up a list of mark files select one and you ll be asked to confirm that you wish
23. they be total or annular as well This makes determining the next total eclipse visible from a given point quite easy to do Finally when done you can go back into the Extras menu and click on Show Eclipse again and Guide will return to charting stars 19 SAVING AND GOING TO MARKS At any time you can save your present view as a mark file and recall it at any future time You do this via the Save a Mark and Go to Mark options in the File menu When you ran INSTALL or SETUP itcopied afew sample mark files to your hard drive Click on Go to Mark and take a look at them The sample marks point to interesting astronomical events and times Gervase occ in 1170 shows Mars crossing in front of Jupiter This sort of planet crossing a planet event occurs about once a 64 century the next time one will occur is in 2065 The most recent was in 1818 The one shown here was recorded by amonk known asGervase of Canterbury in 1170 and also by the Chinese Imperial Observatory Another mark file Earth transit from Mars shows the Earth silhouetted against the Sun as seen from Mars This sort of event is called a transit from time to time we on Earth see Venus and Mercury cross the Sun s disk Such events do not occur frequently for example transits of Venus as seen from Earth occurred in 1874 and 1882 and the next transits will occur in 2004 2012 and 2117 The particular event shown here was calculated by Jean Meeus see
24. to delete that mark file 20 USER ADDED TDF DATASETS As delivered Guide displays an extremely wide variety of datasets covering many kinds of celestial objects However some people will have the need or desire to add objects from completely separate datasets previously unknown to Guide The user added dataset capability lets you do this It also allows you to display and get information from a long list of datasets already created by others such as quasars pulsars double stars and more In fact people usually use the datasets already added by others only occasionally getting around to adding their own We ll describe first how to use these datasets before explaining how to add new ones 65 The Toggle User Datasets option in the Extras menu controls the display of these pre defined datasets When you first use this only the pre defined datasets will be shown in the list box and you can turn them on or off select colors and tell Guide at what fields of view and to what magnitude they should be shown Once displayed you can right click on the objects and get more info data just as with any other dataset As with many other types of objects shown on Guide s charts you can also right click on them and then on display then turn them on or off etc You can also find objects in these datasets using the Go to TDF Object option described on page 8 And now for adiscussion of how to add your own datasets The ba
25. to leave automatic spacing on at first If you would like to override Guide s judgment click on the spacing desired in each column and automatic spacing will be turned off After having adjusted the spacing to what you think it should be you can click Automatic Spacing on again and Guide will follow your judgment when you change levels Similarly by default the marking will be shown in the J2000 0 epoch Click on the Epoch line however and you will be prompted to enter the new epoch for this marking The fact that different markings can use different epochs allows you to for example use a J2000 0 grid with B1950 0 ticks Also by default all markings are in equatorial coordinates that is they define spacings in RA dec But you do have the option of selecting ecliptic alt az horizon or galactic coordinate markings instead Finally you ll notice a box to select the color of the marking in question The remaining seven items each bring up fairly simple submenus in which only the color selection and on off radio buttons are available The only exception isthe Aperture option This option lets you specify the size of a circle to be drawn superimposed at the center of the chart In this case the submenu lets you enter the size of this circle This is usually used to show the apparent angular field of view of a telescope For example if your telescope has with a particular eyepiece a 74 degree field of view you c
26. toggles display of a little floating dialog box loosely modelled on the LX 200 control pad The next step is alignment For this purpose systems fall into two categories the JMI MG III encoder based systems and everything else JMI MG III is used as a shorthand to refer to a huge range of devices the JMI NGC Max series the MicroGuider III Ouranos Lumicon Advanced AstroMaster Orion Sky Wizard B Box and a few others Despite the variety of labels all of these are actually made by Tangent Instruments and are also referred to as Tangent Instrument boxes JMI MG III type systems are also called dumb boxes because all they return to the PC is the position of the encoders The PC is expected to provide the brains needed to convert encoder readouts to RA dec data All the other devices such as the LX 200 and Ultima 2000 have built in alignment systems Once you have aligned them typically by pointing them at one or more known reference stars Guide is ready to communicate with them But for JMI MG III type systems the alignment has to be done using Guide The process is described in the next chapter As with the LX 200 control pad the Scope Pad provides four buttons to allow motion north south east and west plus a central stop moving button and there are four rates of motion provided Obviously none of these work with encoder based systems Such systems don t have motors with which to move the telescope The
27. used in printed charts When Color Stars is turned on stars are colored by spectral type red for cool class M stars blue for hot type O stars yellow for class G stars such as the Sun and so forth Color Stars on only has effect for stars for which spectral information is available this usually means stars brighter than about magnitude 10 The Mag Range and Star Size items let you adjust the size of the circles used to display stars The brightest star visible in Guide Sirius is about five million times brighter than the dimmest star visible This range can t be shown on the monitor A range of 10 magnitudes a factor of 10000 is the default but the Mag Range may be set differently Also you can set limits as to how large or small a star can be with Min Star Size and Max Star Size Combined these three options give you complete control over the relationship between magnitude and dot size The next nine items all control the display of labels for stars They cycle from Auto to On then to Off then to Auto again a three way switch When a marking is on On or Off Guide will ignore its own judgment and either always show or always not show the marking When it is on Auto Guide uses a predetermined set of rules designed to minimize clutter Mag Labels labels all stars down to the indicated brightness level by magnitude You might have achart showing stars down to magnitude 15 but you wouldn t want all of th
28. very interested in finding positions to within a fraction of an arcsecond and succeeded in this goal but good magnitude measurement wasn t apriority The documentation for Al 0 states bluntly that the photometry is as bad as it can be while still being able to claim that the numbers mean something The USNO B1 0 catalog was the successor to A2 0 It contains about a billion objects with slightly better accuracy in both positions and magnitudes In this case up to five plates were scanned for each part of the sky GSC 2 3 is the successor to the GSC 1 1 and GSC ACT catalogs It resembles B1 0 but was assembled by the Space Telescope Science Institute STScI in some cases from different sources and using different methods So it may catch some objects missed by B1 0 while missing a few that B1 0 includes The UCAC 2 catalog is the second version of what will probably become the standard catalog of choice for stars down to about mag 15 or 16 Its positional accuracy is unmatched Unfortunately it includes only stars south of declination 45 or so the actual northern limit varies with declination The release of the final version covering the entire sky should happen soon CMC 14 goes about a magnitude deeper than UCAC 2 with slightly greater astrometric and photometric accuracy But it 58 only covers most of a band between declinations 30 and 50 and has no proper motion data 17c INSTALLING TO THE HARD DRIVE By de
29. with the right mouse button on the time shown in the legend area Clicking on any of the twelve month keys resets the time to the same date in that month Outside the Time Box hit Alt 0 to reset the time to midnight UT If you want to reset the date time by typing in something like 2008 Jan 17 or 11 Dec 4 42 or 13 26 use the Enter Time feature in the Settings menu page 30 or left click on the time zone shown in the legend 15 PLANETARY ANIMATION AND EPHEMERIS CREATION Using the Animation Menu you can watch planets asteroids satellites comets and stars move in time lapse animation This menu may also be used to record the tracks left by an object over time or to list ephemerides in a file For reasons that will become apparent animation ephemerides and tracks are linked concepts in Guide From the main menu use the Animation option The Animation Menu looks like this Animation Dialog Add a Trail 46 Make Ephemeris Make an AVI By default the Add a Trail and Make Ephemeris options are grayed out until you have specified a moving object one within the solar system by right clicking on it To use animation turn on the Animation Dialog and zoom and pan the chart area to show the solar system object s you want to see animated Set the animation rate in the dialog to the desired value You may set step sizes from one second to over ahundred years either directly by clicking on the button showing th
30. 5 Slew LX 200 to Guide posn p 40 Slew Guide to LX 200 posn p 40 Toggle Chart mode p 28 Move CCD frame to cursor loc p 24 Enter a date and time p 30 RA dec format dialog p 31 Set line of variation p 62 Extract objects from MPC file p 62 85 INDEX Al 0 A2 0 Abell galaxy clusters Finding amp definition Turning on or off labelling Abell nebulae Accuracy Altitude Azimuth defined Entering an alt az For grids ticks etc Altitude above sea level Angular distances Animation Aperture ring display Arp galaxy catalog Artificial satellites Asteroids Accuracy of positions Adding new ones by elements Adding from MPC data Asteroid Options dialog Currently bright Displaying amp Labelling Finding AVI movie making Azimuth See Altitude Barnard nebulae Bayer Greek letters Definition Finding by Turning on and off BMP Windows Bitmap files Border Bright Star Catalog Displaying numbers Calendars Camera frame Caption CGCG galaxy catalog Chart mode Color printouts Comets Adding new ones by elements Adding from MPC data Accuracy of positions Currently bright Displaying Finding Common star names finding by Constellations Boundaries lines labels Finding 86 12 Turning on and off Coordinates menu Data Shown menu Declination definition Format Deep Sky Object images Direct to Screen Double stars Finding Durchmusterung Eclipses Ecliptic co
31. 7 lines in this dataset sort 1 The dataset is sorted in increasing RA type 4 The dataset is shown with symbol 4 galaxy type scl5 e0 0 32 c1 H20 20 12 E 20 20 12 c2 m 45 0 145 0 c14 type sc4 f3 10 5 10 5 0 10 c2 Above two lines are user created symbols align 32 The text labels are aligned at the bottom left The first line tells Guide that magnitudes are stored in columns 40 44 of each record This will be used in for example determining the size at which stars are drawn Along with the sizs size in decimal seconds one can use a sizm size in minutes or sizd size in degrees resize is useful for converting a diameter to a radius as shown above or for converting from arbitrary size units The text line tells Guide what data to use in labelling objects if any some datasets don t have any designation to add to the object If the dataset doesn t start right at the beginning of the file you 67 will have to add the offset keyword to tell Guide how many bytes to skip This will always be needed with FITS files In general if you are dealing with simple text files you can ignore the line size nlines and sort keywords But if every record is exactly the same length as happens in many text files and in all FITS files it can improve speed if you provide these fields If the dataset has no carriage return or line feed at the end of each line they are absolutely
32. CONTENTS 1 2 Installing Guide 2 2 Getting Help 3 3 What Guide is showing you 4 4 Panning and zooming 5 5 Finding objects 5a 8 Finding stars 5b 10 Finding galaxies 5c 12 Finding nebulae 5d 12 Entering coordinates 6 13 Getting information about objects 6a 15 Measuring angular distances on the screen 6b 15 Quick info 7 16 The Display menu 7a 17 The Star Display menu 7b 19 The Data Shown menu 7c 21 Planet display 7d 23 The Camera Frame menu 7e 24 The Legend Menu 7f 26 Measurement markings grids ticks etc 7g 28 Backgrounds dialog 8 29 Changing settings 8a 34 Location dialog 8b 35 Inversion dialog 9 36 Overlays menu 10 38 User Object menu 11 38 Telescope control 12 42 DOS Printer setup and printing 13 43 PostScript charts 14 44 The time menu 15 46 Planetary animation and ephemeris generation 16 50 Tables menu 17 52 Extras menu 17a 54 DSS RealSky Images 17b 56 Downloading star data from the Internet 17c 59 Installing to the hard drive 17d 60 Asteroid options 18 62 Eclipses occultations transits 19 64 Saving and going to marks 20 65 User added TDF datasets 20a 68 Defining your own custom TDF symbols 20b 69 Providing TDF limits in RA and declination 20c 70 Adding More Info and click data for TDFs 20d 71 Adding note files for TDF datasets 21 71 Adding your own notes for objects 22 72 About Guide s data 23 74 Accessing Guide s data fro
33. Display menu Strasbourg nebulae Supergalactic coordinates Entering supergalactic coords Shown in legend Tables menu TDF Text Definition File Telescope control Ticks Time menu Direct entry of time Time zone TLE definition Toolbar Trail generation Transits of Mercury Venus Twilight times Tycho Catalog Uppsala galaxy catalog UGC Uranometria page number display User added datasets Adding notes for Custom symbols Description Finding objects in Turning on and off User Object menu van den Bergh nebulae Variable Stars finding Displaying amp Labelling Variation line of VSOP Yale Catalog See Bright Star Zooming in and out Zwicky galaxy clusters Finding definition Turning on or off labelling 90 died 20
34. File menu Go To menu p 5 Help menu p 2 Inversion menu p 35 Go to comet p 7 Toolbar dialog p 33 Full horizon view Overlays menu p 36 84 Alt period Alt Shift F1 Shift F4 Shift F6 Shift F12 Ctrl A Ctrl B Ctrl D Ctrl E Ctrl F Ctrl G Ctrl H Ctrl K Ctrl L Ctrl N Ctrl R Ctrl T Ctrl V Ctrl X Ctrl Y Ctrl Z Ctrl F1 Ctrl F2 Ctrl F3 Ctrl F8 Ctrl F9 Ctrl F10 Ctrl F11 Ctrl F12 Create PostScript chart p 43 Quick Info p 15 Toggle between red screens and normal colors p 28 Settings menu p 29 Time menu p 44 Find opposition point p 12 Horizon dialog p 6 Extras menu p 52 Toggle north zenith up p 36 Increase planet feature details p 22 Decrease planet feature details p 22 Toggle to Japanese Quit Guide Extract RealSky DSS image p 54 Toggle user datasets p 53 Clear all RealSky DSS images p 54 RA dec format dialog p 31 Table of satellite passes p 51 Toggle to Czech Toggle to Chinese Toggle animation on off p 47 Find a Bayer or Flamsteed star p 9 Data Shown p 19 Toggle scope pad p 40 Toggle camera frame p 53 Toggle fixed levels p 23 Select home planet p 34 Add a new comet or asteroid p 80 Toggle legend p 24 Find NSV star p 9 Switch to Russian Measurement markings menu p 26 Find a variable star p 9 Enter longitude p 34 Enter latitude p 34 Enter altitude p 3
35. Ifyou are interested in the mathematical methods of astronomy this book is a must Information on this and other books used in creating Guide is at http www projectpluto com books htm 75 Special thanks go to the translators for the various foreign language versions of Guide Eric Sven Vesting German Jean Noel Moreau French Alberto Romero Spanish Giuliano Pinto Italian Guus Gilein and Siebren Klein Dutch Masaki Kouda Japanese Alexander Anikeev Russian Jan Manek Czech David Wu Chinese Jozsef Lengyel Hungarian and Marcin Siekierko Polish These people are all native speaking astronomy enthusiasts exactly the right people to do this sort of technical translations These versions have been immensely helpful in making Guide easier for most of the world to use Most of the improvements incorporated since versions 1 0 through the present version were suggested by users on the response forms Thanks go to all who took the time to indicate what was useful what would be useful and what was really a bad idea APPENDIX A RIGHT ASCENSION AND DECLINATION Right ascension RA and declination are the celestial versions of longitude and latitude on the Earth The celestial versions of the poles are found by taking the Earth s axis of rotation which of course passes through the North and South poles and extending it into infinity The celestial equator is found by extending the Earth s equator into infinity
36. add to the legend area such as Occultation of P17 by Pluto or Area around M 49 You may wish to add multiple lines suppose for example that you want to make achart showing the asteroid 111 Ate passing through the galaxy M 104 and the chart is for use by the East Overshoe Astronomical Society You might want the following three line caption Asteroid 111 Ate 25 As seen in area of M 104 East Overshoe Astronomical Society To enter these three lines you would first clear any existing caption using Clear Caption Next you would click on Add to Caption and enter Asteroid 111 Ate You would then click the option twice more and enter the remaining two lines Make sure that the caption is turned on by clicking on Caption Off if necessary When you leave the menu the chart will redraw and the new caption will be shown You also can change the Layout of the legend A Vertical layout makes the legend much taller than it is wide a Horizontal is wide You can switch the legend between the bottom or top of the chart and move it to the left right or center By default Guide uses a vertical layout in the bottom left 7f Measurement Markings Ticks Grids etc The Measurement Markings menu controls the features to measure positions and sizes in Guide The menu looks something like this Ticks Grids Side Labels Hatches Ecliptic Horizon Gal Equator Telrad Aperture Central x hair Border The first four
37. aila 48 Clear Trails Cancel With the above settings you would be telling Guide to show the trail for an object at ten minute intervals for 100 such intervals At every twenty minutes there would be an index mark tick mark crossing the trail There would be labels showing times along the track at every sixth step that is for each hour By default the Round to nearest step box would be checked This would mean that if Guide s time was say 03 14 15 9 this would be rounded off to the nearest ten minutes and the starting point of the trail would be 03 10 00 0 Also provided in the Add A Trail dialog is a button showing the color in which the trail will be drawn you can click on that button to select a different color The Clear Trails button lets you erase all trails of moving objects However as with so many things in Guide you can click on a trail with the right mouse button then tell Guide what color you want for that trail or delete it Once this setup work is done you can click the Add Trail button and Guide will pause briefly tocompute and display the trail in question Guide will automatically save your trails when you exit the program and will bring them back up when you restart the program The trails are stored as an overlay which means you can control their display in the Overlay menu You can add text lines and circles to the trails select the fields of view where they can be shown and remove un
38. an be a little disconcerting for the rest of us While the Hipparcos Tycho Catalogs and GSC are used for display of stars when you click for More Info on a star you may get data from many other catalogs Guide will attempt to cross reference to the SAO Smithsonian Astrophysical Observatory HD Henry Draper Yale GCVS General Catalog of Variable Stars WDS Washington Double Star PPM Position and Proper Motion and NSV New Suspected Variable catalogs Each will either provide additional data or a cross check on the data you ve seen in other catalogs or both There are five galaxy catalogs on the Guide CD ROM The PGC Principal Galaxy Catalog 1996 of over 100 000 galaxies forms the basis for display of small fields Data is also shown from the RC3 Third Revised Catalog the Uppsala General Catalog UGC the Morphological Catalog of Galaxies MCG and the European Southern Observatory extension to the UGC ESO Uppsala As with any other problem you may find with Guide please let us know if you find any problems in the data At the very least error reports can be passed on to those maintaining the data 73 23 ACCESSING GUIDE S DATA Quite afew programmers have asked about accessing the data on the Guide CD ROM from their own programs In certain cases this can be easy to do some of the data for example all of the user datasets are in their original ASCII form and are well documented In others it can
39. are designated by double star catalog and number for instance ADS Aitken Double Star orStruve number When you select the Double Star option alist of over 130 double star catalogs all named after their discoverers is shown The Supernova option looks for supernovae that have occurred in other galaxies Over 1000 have been observed the first was in our neighboring galaxy M 31 in Andromeda Apart from that supernova and one in the Large Magellanic Cloud in 1987 no supernova outside our galaxy has been bright enough to be visible to the unaided eye Supernovae are designated by ayear and a letter e g 1993J or 1885A The Durchmusterung option provides a way to find stars in the four catalogs of the DM Catalog These are known as the Bonner Durchmusterung BD which covers stars in the northern half of the sky the Sudentliche Durchmusterung SD which covers stars between declinations 1 and 23 degrees the Cordoba Durchmusterung CD which covers declinations 22 to 90 and the Cape Photographic Durchmusterung CP which covers 18 to 90 You ll notice that these catalogs overlap in places The designation consists of the catalog abbreviation BD SD CD and CP followed by the zone number followed by the star number For example BD 32 724 CPs 67 T233 In the Hipparcos option enter an Hipparcos catalog number to recenter on that object 5b Finding galaxies The Galaxy option in the Go to menu provides wa
40. atically adjust the limiting magnitude as one zooms in or out in an attempt to maintain a constant density of objects This is always done for stars for example But in fixed mode you are essentially telling Guide that you want a class of object to be shown to a particular limiting magnitude and that the zoom level should be ignored If an object class is turned On or Off the magnitude limit is irrelevant and is therefore grayed out Next to these four radio buttons there is usually a labelling button and a button to select the color for that class of object For Gal Clusters the panel shows an extra three way switch between Zwicky On Abell On and Abell Zwicky On The Abell catalog of 20 clusters of galaxies covers the entire sky and contains over 5 000 objects The Zwicky catalog only covers the northern half of the sky but it has over 9 000 objects Some objects are found in both catalogs Depending on where you are in the sky you may wish to see the Abell clusters the Zwicky clusters or both All three are possible and a check mark is placed in the menu beside the current selection The Asteroids submenu also shows some extra options controlling the labelling of asteroids asteroids labelled by number asteroids labelled by number if available provisional designation otherwise asteroids labelled by name provisional designation otherwise By default asteroids are labelled with their number Unnumbered aste
41. cal Observatory catalog lists more 258 997 stars but has less information per star than the Bright Star Catalog Astronomy magazines will often define astar byitsSAO number The more recent PPM Position and Proper Motion catalog lists slightly more stars than the SAO catalog It was intended as a more accurate replacement for the SAO The HD Henry Draper catalog compiled early in the 1900s lists over 359 000 stars The Guide Star option lets you find a star by Hubble Guide Star Catalog number The GSC lists over 15 million objects and forms the basis of the more detailed layers of Guide s data but only provides a star s location and brightness or astronomical magnitude See page 81 AGSC designation consists of azone number between 1 and 9537 anda star number within that zone usually but not always less than 10000 Many variables are designated by one or two letters and aconstellation like RCoronae Borealis R CrB or UV Ceti UV Cet The rules used for these designations allow 334 designations of this type per constellation further variables are given anumber following aV Thus V335 Ori is the first variable found in Orion after letter designations were exhausted The NSV New Catalog of Suspected Variables is mostly of interest to variable star observers It lists over 14 000 stars that someone has thought might beavariable but which haven t been studied well enough to be sure of the matter Double stars
42. cceeds in communicating with the scope it will move to the next step You ll see a small dialog box asking if you have an equatorial reading hour angle an alt az an alt az scope on an equatorial platform or an equatorial reading RA The alt az options are straightforward enough but the equatorial options require some explanation It seems that encoders on equatorial scopes are about evenly divided between two mounting methods Some people use one encoder to measure the hour angle at which a telescope 4 is pointed with the drive motor on this encoder reads a changing value as the scope moves Other people though will use one encoder to measure the RA at which the telescope is pointed In such a case the drive motor doesn t force the encoder to move Unfortunately Guide has no way to determine which system you re using So when you add the first alignment star it will ask you for this information Click on the Scope Pad option and you ll get asmall dialog box with assorted scope control commands The next step is to add at least two alignment stars To add an alignment star you first find it in Guide by panning or using Go To commands or whatever you wish and clicking on it with the right mouse button When you get the short dialog box describing the star click OK Next point the telescope at this alignment star Once you have it centered click Add Alignment Star in the scope pad Guide will add that
43. cked on say an asteroid and then clicked Display you would getasomewhat different setofcontrols including options specific to asteroid display Clicking on More Info leads logically to more information The amount and type of information will depend on the object For some objects Guide may be able to find information in a half dozen catalogs for obscure objects perhaps only one On Acubens More Info is about 150 lines of data First data from the Hipparcos catalog is provided giving such details as position magnitude and proper motion Many terms are in light blue you can click on them to get information about them In fact the remarks data is an extension of the help system so you can get added information about the remarks in the same way Again you can save the data to a file or print it After the raw data from Hipparcos some information such as distance and luminosity derived from that data is shown Then Guide gives information from the Tycho GSC PPM SAO WDS HD and Yale Bright Star catalogs This serves several purposes Some of the other catalogs just give data backing up the information from previous catalogs A few provide unique information for example the WDS Washington Double Star catalog tells us that this is a double star with magnitudes 4 25 and 11 8 A catalog such as the GCVS will tell you what type of variable star this is how much it varies by and its period of variation 14 This amo
44. ct fainter objects and the current Tycho 2 catalog has about 2 5 million stars Tycho attempts to be complete down to the limit of what the instrument in the satellite could observe about magnitude 12 and measured the same things as Hipparcos But its precision is considerably less than that of Hipparcos The magnitudes and positions are still better than those from any other catalog The Hubble Guide Star Catalog GSC version 1 3 is used for dimmer stars down to about magnitude 14 or 15 This version is also known as GSC ACT Originally it was created for use in fine tuning the aim of the Hubble Space Telescope It is the most detailed star catalog widely available with about 15 million stars However it does have some oddities It was generated by scanning in survey plates from two telescopes the Palomar Schmidt camera in California and the U K telescope in Australia As with the SAO the main intent was to get enough stars to be confident of having some guide stars in a given field of view In dense areas such as Sagittarius they could get away with a magnitude 13 limit and would have the required density In vacant areas like Virgo it was necessary to go to mag 15 or 16 That s why the limiting 72 magnitude of the GSC and of Guide varies as you move in the sky Objects were automatically collected and classified as stars or non stars with varying degrees of accuracy thus the switch to turn off Non Stars inthe S
45. d no questions asked We would naturally like to know any thoughts you might have that could contribute to a better product and if you re willing to volunteer your reasons please do so it will be appreciated The above is governed by the laws of the State of Maine The Nebula Databank and isophote data are copyrighted by Eric Sven Vesting and are used in Guide by permission This software makes use of a subset of the JPL DE 406 ephemerides These ephemerides were created by the Jet Propulsion Laboratory http www jpl nasa gov The complete versions of these ephemerides as well as for DE 200 are available on a CD ROM distributed by Willmann Bell http www willbell com The subset provided with this software is distributed by permission of Willmann Bell APPENDIX I LIST OF PROGRAM WIDE HOTKEYS The following hotkeys can be used at any point in Guide You can get this list by hitting the key Be aware that almost all of these hotkeys have corresponding menu options All of them plus some functions deemed too minor to merit hotkeys of their own can be accessed via the toolbar see page 33 Some people are keyboard oriented and like having all functions just a keystroke away And if you find that you need to enter a few dozen ecliptic coordinates it may be easier to hit Alt Comma_ than to navigate the menus each time But in most cases you will find it easier to use the menu options than the hotkeys Hotk
46. de is bright enough to realize that conjunctions occur at roughly 27 day intervals you can click on Find Conjunction repeatedly to show subsequent conjunctions Alternatively or in addition you can click on Show Eclipse Guide will clear the screen and switch from drawing charts of stars to drawing charts of the earth you ll get a world map and the path of the event in question will be shown Depending on your computer speed this may take a few seconds it is a very math intensive task The eclipse path will usually be in light gray shading to blue in regions where the sun is above or near the horizon Also regions where an eclipse is partial will be shown in various shades Keeping in mind that for occultations of stars there is no such thing as a partial eclipse Of course it s always possible that Guide won t find an eclipse because one didn t happen that time If the moon is one of the two objects you clicked on Guide will again be bright enough to check for eclipses in subsequent months until it finds one It can apply a similar search for transits of Mercury and Venus In all other 63 cases you ll get an Eclipse not found message if the event isn t visible from Earth Many of the techniques used in drawing sky charts have been recycled for the earth eclipse charts You can zoom in or out print charts set display levels and so forth much as you did before If you right click on the chart you ca
47. e a different toolbar The Toolbar dialog also provides a Max menu length option This defaults to 99 but if you set it to for example 3 then the menu options on the top line will be abbreviated to three letters in length Settings will become Set for example The main advantage of this is that it can allow you to fit more toolbar buttons onto the top line If too many buttons are selected the excess simply forms a second or third row of toolbar buttons But such extra rows cut into the chart area Finally you can select a Use Large Buttons check box The large buttons are about twice the size of the standard buttons Large buttons are not available for all options in such cases 33 the small buttons are used instead 8a Location dialog The Location dialog controls your point of view on the earth or on other planets and satellites The dialog looks like this Earth Longitude W 69 900 Latitude N 44 010 Altitude 100m Enter location name Use geocentric position Include refraction Humidity 20 Temperature 20 C Pressure 760 mm Hg The very first item tells you from where you are looking at the sky If you click on it you will get a long list of Solar System objects You can select one and after that all planets moons and so on will be drawn from that planet or satellite You can see what Jupiter and its moons look like from one of Jupiter s moons or what the Earth looks like from the M
48. e 2 and so on down to magnitude 6 This was based strictly on looking at the star and guessing how bright it was The invention of the telescope revealed objects fainter than mag 6 81 so the scale was extended to higher numbers It was eventually decided that five magnitudes should represent a change in brightness of a hundred fold that is a mag 2 star should be 100 times brighter than a mag 7 star This also means that each magnitude represents a 2 512 fold change in brightness This is asomewhat unwieldy number but we re stuck with it now This system means that one can measure fractions of a magnitude Polaris for example is a mag 2 02 star and that really bright objects can have negative magnitudes Sirius is mag 1 58 Venus can be as bright as mag 4 4 the Sun is magnitude 26 It is still true however that most humans cannot see an object fainter than mag 6 though this limit varies among humans APPENDIX H COPYRIGHT AND LIABILITY NOTICES Charts you create using Guide are NOT copyrighted by Project Pluto You can freely copy and distribute charts and graphics files that you have generated as long as mention is made of the fact that Guide was used to create the chart or graphic This program its data this manual and the use of the names Guide and Project Pluto are copyrighted 1993 2008 by Project Pluto and its licensor All rights reserved It is illegal to copy the aforementioned items without written permiss
49. e a tilde plus name system since tilde plus number would not be very helpful The system can even be extended to cover datasets you have added to Guide with the user added dataset system see page 71 for details 22 ABOUT GUIDE S DATA As has been mentioned Guide draws its data from a number of sources It can be helpful to know something about these sources their limits purposes and uses This chapter will discuss these issues For stars brighter than about mag 11 Guide uses the Hipparcos and Tycho 2 Catalogs These catalogs were both generated by the European Space Agency ESA Hipparcos satellite and are often spoken of as if they were essentially identical They are not and in some cases the differences can be very significant The Hipparcos catalog contains 118 218 stars that were primary targets for observation Most are bright stars but afew dimmer stars that were of special interest were included mostly nearby stars and some variables The satellite gathered positions to a precision of about 001 arcsecond and highly precise proper motions parallax distance data and magnitudes in visual and blue systems for these stars Some were more precise some less so the specific data for each star is listed when you ask for More Info about it The Tycho catalog contains a total of over 2 5 million stars Tycho has been released in two versions Tycho 1 had about 1 million stars but the data was reprocessed to dete
50. e animation rate in the dialog or by using the Faster and Slower buttons in the dialog Once you have set the desired rate you can click on the double arrow animate forward button inthe Animation Dialogue and solar system objects will start to move You can then click on the central stop animation box when done The remaining arrows allow you to run the process backward or to take single steps in time forward or backward For your first few efforts you will probably do well to start with a small step size and work your way up You can also run animation in real time the objects move according to the actual time as provided by the computer s built in clock by clicking on Real Time When you do this Guide will ask you how often the display should be updated If you re following a rapidly moving artificial satellite it may be necessary to update its position once a second when in Real Time mode But when following a slower moving asteroid or planet an update rate of once a minute or even less may work nicely Clicking on Real Time again returns you to your previous rate of animation The animation dialog contains three extra very important buttons in the Locked On box Moving Object Horizon Stars In the default Locked on Stars mode the animation stays fixed relative to the stars You may still see stars move due to proper motion if the animation step size is large enough but they stay basicall
51. e charts instead of celestial north or ecliptic north or galactic north and in addition to that rotation you can add an arbitrary amount of rotation to the charts The Inversion option is discussed on page 35 The Ticks Grids Etc option page 26 provides 16 controls over all the markings used to illustrate measurements and coordinate systems grids ticks hatches the Telrad sight aperture circle and so on In the Screen Font or Printer Font options you may choose a new font for the device you selected Usually when Guide draws a chart on the screen everything is erased and then stars overlays text and objects in the window are drawn You see the whole process as it happens This is the default method where things are drawn directly to the screen The Direct to screen lets you turn this option off In that case Guide first draws the chart in memory and when it is ready displays it on the monitor On some video cards this may be faster than the default mode and itis almost essential in some animation modes Also some people just prefer not to see the process of the chart being created It may be best just to try it and draw your own conclusions In the Backgrounds option page 28 you may switch from the default white stars on black to black stars on white to a red mode for use at the telescope and control the display of objects ground trees houses mountains on the horizon Guide shows the Mil
52. e menu A standard printer setup 42 menu is shown In Portrait mode the chart will make the top be the short edge in Landscape mode it will be on the longer edge By default there are half inch margins on all sides The Margins menu found under Settings lets you reset these values For example in making the cover for this manual the back cover was printed with the right hand margin set to 5 8 inches The front cover was printed with the left hand margin set to 5 8 inches and the top margin set to 3 inches to make room for the title All other margins were left at default values The Margins menu also provides check boxes to determine which sides get RA dec labels You may decide for example that the top and left sides should get RA dec labels or all four sides or all except the left side each possibility is used by at least one standard printed star atlas Keep in mind that this is only used if side labels are turned on in the first place see page 26 One subtlety in how printing is done shows up in the Backgrounds dialog see page 28 When in normal mode all printing is in black and white even on color printers Only in chart mode where the chart on screen has a white background are charts printed in color If stars come out at sizes other than those you would want you should check the Min Size Max Size and Mag Range options in the Star Display dialog see page 17 It often happens that the
53. e of these files is in the Guide directory the Use MPCORB option will no longer be grayed out Toggling it on will cause Guide to use the elements in MPCORB while ignoring the asteroid data built into the Guide disk Switching to MPCORB has advantages and disadvantages and it s important to understand both The data on the Guide disk includes alot of pre computed information regarding where each asteroid will be over a given time and how bright it will get this allows Guide to display asteroids almost immediately as long as your location is on Earth Elements are provided covering a range of several decades so perturbations are modelled with good accuracy over that entire range But of course the built in asteroid data can t be rewritten You re stuck with the data as it appears on the CD ROM and newly discovered asteroids and orbits updated based on new data will not be included This is where MPCORB has a great advantage the MPC updates it almost daily People engaged in asteroid discovery and astrometry measurement of positions will sometimes find MPCORB to be useful or even essential and will accept the fact that it slows Guide down immensely Such people are also usually concerned only with current information so the fact that perturbations are ignored when MPCORB is in use will not matter much to them Most people though will instead stick with the built in asteroid data in Guide And when dealing with da
54. em labelled by magnitude it would be too crowded So you would set alimit of perhaps magnitude 11 here If you set a proper motion vector length of for example 1000 years each star will appear with a short line indicating the direction and amount of its motion over 1000 years By increasing this value you can get the motions of slower stars to be apparent A value of 18 1000 years is used in the charts of the Millennium Star Atlas and seems to work well in most Guide charts as well Some people find these vectors to be distracting therefore the default length is O years that is no vector at all Non Stars toggles the display of objects labelled as non stars inthe Hubble Guide Star catalog The GSC was automatically generated and a computer classified non starlike objects on the photographic plates scratches asteroids galaxies nebulae and some stars that confused the computer as non stars Most are really misclassified stars so Guide displays them by default in green If you don t want to see them shut them off with this switch By default Guide shows bright stars using their visual magnitudes on the Johnson photometric system called Vj This is true for stars from the USNO A2 0 catalogues described on page 58 or the Tycho catalogue described on page 72 Click on the Vj box and you get achoice of alternative photometric systems Select one and Guide will switch to use of that system Please be awa
55. er letters page 3 refer to stars with a Greek letter followed by a constellation for example Alpha Centauri Gamma Cygni or Mu Cephei Flamsteed numbers 8 also refer to slightly dimmer stars they consist of a number followed by a constellation such as 40 Eridani or 61 Cygni Click on this option and you get a list of the 88 constellations Select one and you will get a list of Bayer and Flamsteed objects in that constellation Bayer objects have aFlamsteed number as well Click on the star you want to recenter on it The brighter stars have names sometimes handed down from ancient civilizations Betelgeuse Sirius Capella Antares and so on Clicking on the Common Name option brings up a list of over 290 common names for stars When you find the star you want click on it and Guide will redraw the chart centered on that star A number of catalogs are described below For each of these catalogs click on the catalog name and enter the designation and Guide will recenter on the star The Nearby Star option will bring up a list of nearby stars Many of these have odd names such as Proxima Centauri Barnard s Star or Kruger 60 that won t appear in any of the standard catalogs This function can be especially useful in such cases The Yale Bright Star Catalog or HR catalog lists 9 096 stars The information in it is mostly of interest to professionals and gung ho amateurs The SAO Smithsonian Astronomi
56. ets and their satellites Click on one and Guide will recenter on it Incidentally there is an extremely useful shortcut hitting for example Ctrl O recenters on the Sun Ctrl 1 on Mercury Ctrl 2 on Venus and so on up to Ctrl 9 on Pluto Use Ctrl Control Minus to recenter on the Moon One goes to planets so often that having them a keystroke away can be really helpful Ctrl 3 will recenter on the earth Unless you ve set Guide to show you the universe from a different planet an option discussed on page 34 that means it will show you the nadir the point directly underneath you By default Guide will show the names of the planets and satellites in red yellow or green Red indicates the object is below the horizon yellow less than ten degrees above the horizon green more than ten degrees above the horizon This color coding also used for lists of comets asteroids and constellations is very helpful in giving you an immediate idea of what is currently visible The next option lets you center Guide on a given planetary feature usually a lunar crater but features are also available on other planets To use it you must first center Guide on the planet in question and zoom in until that planet shows a disk Then use the Planet Feature option and Guide will list planetary features currently in view Select one and Guide will center on that feature Three comments are important First a feature on the
57. ets you select a new file of orbital elements for artificial satellites Artificial satellite elements are almost always provided in files called Two Line Elements or TLEs these files usually have a TLE extension You will need to get updated files quite often Satellite motion is not entirely predictable satellites maneuver using thruster rockets new satellites are launched and the way in which atmospheric drag works can t be predicted very far in advance The model used for satellite motion was provided by the US Government and is mediocre the really good motion models are classified In fact the TLEs provided with Guide will already be somewhat out of date by the time you get this CD You might be able to get say an approximate time at which ISS will pass overhead But getting current data is a good idea When you click on the TLE _ option you ll see some information about sites where you can get satellite elements with links provided In most cases you can simply click on an option to download data for all satellites or for a specific group of satellites The Projections submenu offers a long list of chart projections stereographic the default orthographic gnomonic Mercator and more Each serves a different purpose Stereographic projection preserves the shapes of objects quite well no matter how large an area is being shown At Level 1 180 degree field of view the other projections will show very dis
58. evels are mostly useful in examining surface details on planets and their satellites At Level 20 one arcsecond a Satellite such as Io just about fills the view You can go directly to a particular level in four different ways To go to a level from 1 to 9 hit a key from 1 to 9 using the numbers above the letters on the keyboard To go to level 10 hit the 0 key To go to levels 11 to 19 hit Alt 1 to Alt 9 You can also move the mouse over the line in the legend showing the current zoom level A box will appear around the zoom level text in the legend Click there and a dialogue box will appear listing all twenty levels Click on one and Guide will go to that level The effect is the same as the 1 9 and Alt 1 through Alt 9 keys but you need not hit the keyboard Since this method avoids any use of the keyboard it is the easiest to use in the dark If the zoom level isn t shown just hit this will bring up the dialogue box By default the toolbar will show buttons for level 1 field 180 degrees afull hemisphere 4 20 degrees 7 2 degrees and 10 1 4 degree These levels are provided by default on the toolbar you can select other levels to be shown there using the Toolbar option in the Settings menu see page 33 Finally if you press and hold the left mouse button at the point on the chart you want to move to and move the mouse you ll drag open a rectangle centered on that point Let go and you ll zoom into
59. ewed on screen then saved to a file or printed Many of the tables include items highlighted in red green or yellow clicking on these generally causes Guide to switch to the time and location of the event or object in question so you can see it on screen The meaning of the colors is discussed below Most of the items generate a list of events during a particular 50 time span For these you set Guide s date and time to the start of the time span click on the menu option and tell Guide for how long a span you want data Suppose you want lunar rise set and libration data for October 1997 You would enter the Time Menu and set the date and time to 1 Oct 1997 Now enter the Tables Menu select the top option and tell Guide you want data for 31 days A window will come up with data for that time span The window includes Save to File and Print options The Jupiter events option will make a list of Jupiter s satellite events the occultations shadows eclipses and transits that are visible with small telescopes It is the sort of list Guide shows in More Info for Jupiter page 15 but you can set the time span instead of settling for a fixed seven days The GRS transits option will make lists of times when the Great Red Spot transits is best placed for viewing If you just want to find out when it will next transit just right click on Jupiter and ask for More Info The Current asteroids and current comets
60. ey Function lt enter gt Force a redraw lt space bar gt Stop a redraw lt esc gt Stop a redraw lt tab gt Toggle full screen mode DOS Zoom in one level Zoom out one level 1 9 Zoom to levels 1 9 0 Zoom to level 10 Alt 1 9 Zoom to levels 11 19 Ctr1 0 Center on Sun 83 Ctrl 1 9 Ctrl Alt 0 V II esn Yee KH HD MUFH Mo gt Center on Mercury Pluto Center on the Moon Set time to midnight UT Increase star sizes Decrease star sizes Increase animation step Decrease animation step Show this list Enter glossary p 2 Find an asteroid p 7 Find a planet p 7 Find a constellation p 8 Shortcut to find solar eclipses p 63 Toggle coloring by spectral type Star display menu p 17 Toggle outlining of stars p 18 Enter an alt az position p 13 Toggle overlays menu p 37 Load a mark file p 64 Save a mark file p 65 Delete a mark file p 65 Select new level Find a variable star p 9 Margins menu Switch to German Switch to Spanish Switch to Italian Switch to French Find IC object Find Messier object Find NGC object Enter help system Print Reset to current time Scope control menu p 38 User Object menu p 38 Reset level size p 31 List all stars on screen p 52 Slew telescope to Guide posn p 40 Slew Guide to telescope posn p 40 Planet animation menu p 46 Tables menu Data Shown p 19 Enter RA and declination p 13
61. f for example Edit Overlay will provide a list of overlays plus a Create new overlay option If you select this create option Guide will ask you to supply the new overlay with aname Certain overlays including constellation lines and boundaries can t be edited They are therefore omitted from the list When you tell Guide that you want to edit an overlay a small floating dialog box appears Its main feature is a set of four radio buttons Normal Mode Add Lines Add Text and Add Circles Each causes the mouse to assume a different function In the Normal Mode the mouse behaves normally right clicking selects objects in the chart and left clicking pans In Add Lines mode the mouse behaves normally except that clicking and dragging the mouse with the right button causes Guide to add that line to the overlay You can then add another line segment with another right click and so on to build up a polygon When in Add Lines mode you can still click on objects to get information about them But instead of just right clicking on them you have to hold the Shift key and right click on them This can be useful if you decide you want to delete a line or two from the overlay you can Shift right click on that segment then on Delete and then pick up from where you left off In Add Circles mode the mouse behaves normally except that clicking and dragging the mouse with the right button causes Guide
62. f recent comets plus new comet and new asteroid entries You can select an existing object to alter it useful for element updates or either class of new object Next you ll get a menu allowing you to adjust and save all the elements labeled above Because orbital data tends to confuse the uninitiated and at times the initiated there is a paragraph or two provided on the screen to clue you in to what the variable in question means After entering all the elements you can save the results and Guide will add that comet or asteroid to its list Keep in mind that the new object obeys the same rules as any comet if you have comets turned off in the Data Shown dialog or if the comet is not brighter a the limiting magnitude for comets it will not show up on the chart Be aware that a particular set of elements is good for a limited time only usually afew months around the epoch Over time gravitational effects of other planets will change the elements and therefore the object position After afew months if the object doesn t come too close to a planet errors of afew arcseconds will accumulate over a few years the errors will grow to a few arcminutes APPENDIX G ASTRONOMICAL MAGNITUDES The creator of the first star catalog Hipparchos was also the creator of the system used to measure the brightness of stars He assigned a magnitude to each star the brightest were magnitude 1 stars those slightly fainter magnitud
63. far side of that object won t be listed Second if you zoom in so far that only part of the planet is shown only those features in the view will be listed So you can for example zoom in on Tycho and get a list of lunar features in the Tycho area For details on how to display these features in Guide see page 22 Third the coloring scheme is slightly different here red means the object is on the night side of the planet yellow within ten degrees of the terminator green n full sunlight In the Comet option Guide will list the comets that are currently visible according to the limits set in the Data Shown dialog p 19 Click on one of them and Guide will recenter on it In the Asteroid option you can specify an asteroid in any of three ways name number or provisional designation The first asteroid to be discovered Ceres may be found by typing in its full name or the number 1 A provisional designation is given when an asteroid is first found This is usually a year followed by one or two letters and zero to three digits such as 1989 AC or 1997 XF11 7 Later when the object has been observed often enough that its orbit is well determined itis given its number and usually aname Enter the provisional designation and Guide will also recenter on that asteroid Bright open clusters have usually been given Messier NGC or IC numbers Others appear in catalogs like Collinder Tombaugh or Berkeley For a
64. fault Guide only installs a few megabytes of essential data to the hard drive and the remainder of the data it needs is read from the CD ROM onan as needed basis This is fine for many uses but there are several possibilities for installing more data or the entire first CD ROM or both Guide CD ROMs or bits and pieces of both CDs to the hard drive To see this click on Extras Install to Hard Drive Guide will give a list of assorted items that can be installed from the hard drive If you just checked the first item Minimum Hard Drive Install Guide would copy over afew more megabytes that would be enough to let you run the program without needing the CD ROM Butit would be a very minimal installation you would see no stars past magnitude 7 0 many datasets would not beincluded and many functions would be unavailable Checking subsequent items soaks up added hard drive space but gives you those added functions Check all the items and Guide will copy over everything from the CD consuming about 660 MBytes Of course you can return later and un check some or all of these items to reclaim the hard drive space Guide will still check the CD ROM drive at startup just to see what data is available If you ve installed only a few items but Guide realizes the first Guide CD ROM is in the drive it will get what it can from the hard drive and access remaining functions and data from the CD ROM If you ve installed some or al
65. g Dipper which seems to be right side up when it s close to the northern horizon looks upside down when you see it high in the sky You would usually turn a paper star chart until it looks correct Also if you have the show ground or horizon objects options set in the Background dialog these may appear tilted If you select alt az zenith up the chart will rotate to show the zenith point directly overhead at the top of the chart If you ve entered your latitude and longitude correctly and if the clock is set to the right time and time zone the chart will now appear right side up and will match what you see in the sky If you have the horizon turned on and it happens to be in the field of view it will now be drawn straight across the screen instead of at an angle Since Guide is still centered on the same point in the sky the effect will be to take the chart and rotate it possibly until it is upside down Having the zenith at the top of the chart is particularly useful if you have an altitude azimuth type of telescope mounting such as a Dobsonian It is also useful for making charts showing a large part of the sky Le low level numbers for naked eye observing The last two radio buttons Ecliptic north up and Galactic north up are not nearly as useful But sometimes people do want charts aligned with these systems 9 OVERLAYS MENU The Overlay menu lets you create and edit your own overlays showing
66. galaxies listed by Halton Arp Many of these objects make for interesting observing with small telescopes Their numbers run from 1 to 338 5c Finding nebulae When you click on the Nebula option in the Go to menu you will get the following menu Sharpless Lynd s Bright Neb PK Strasbourg Van den Bergh Barnard Dark Neb Common Name Abell Planetary To find an object by its Sharpless Lynd s Bright Nebula Abell van den Bergh or Barnard number click on the option and type in the catalog number Guide will recenter on that object By the way don t confuse the Abell catalog of planetary nebulae with the Abell catalog of clusters of galaxies p The PK Perek Kohoutek or Strasbourg catalog of nebulae requires a pair of numbers These numbers actually form a coordinate for the object For this option you enter both numbers as in 249 5 1 or 215 11 1 The numbers will be separated by either a plus or minus sign Most nebulae are known by their common names such as the Eskimo nebula or the Trifid nebula The Common Name menu provides alist of these names from which to choose 5d Entering coordinates Guide has provisions for entering coordinates in five different systems equatorial RA dec ecliptic galactic supergalactic and alt az Entering coordinates is a fairly common task so in Guide you can do it in several ways If coordinates in any of these systems are shown in the Legend you can just
67. gquasarsablel dat title Quasars The stands for the CD ROM drive letter it probably will be of little use to you since your datasets will come from someplace else These lines of course simply tell Guide where to find the data and what to call the dataset when it s listed in dialog boxes Each dataset ends with the 66 shown 0 end commands or shown l end if the dataset is turned on The lines in between however will vary widely between datasets All datasets will have adescription of the format of coordinates For example RA H 20 2 RAM 23 2 RA S 26 4 de d 30 3 de m 34 2 de s 37 2 tells Guide that in this dataset the RA hours of an object is stored in columns 20 21 ofeach line the RA minutes in columns 23 24 and the RA seconds in columns 26 29 Quite afew datasets will omit the RA S de s and or de m fields because they use decimal degrees or minutes this is not a problem for Guide The following lines may also appear in a dataset description mag 40 5 Magnitude is in columns 40 to 44 sizs 33 5 Size in decimal seconds in columns 33 to 37 resize 5 Multiply size by 5 to convert diameter to radius text 2 17 Text for labelling this object in columns 2 18 epoch 1950 This dataset provides B1950 0 coordinates offset 23040 The actual data starts 23 040 bytes into the file line size 102 Each line in this dataset is 102 characters nlines 7437 There are 743
68. he CGCG Catalog of Galaxies and Clusters of Galaxies is commonly used for labelling northern galaxies In both of these catalogs galaxies are designated by two numbers again separated by a space or dash as in ESO 34 12 or CGCG 17 41 Again as with the MCG a letter is sometimes added to this Again you can use either a space or dash to separate the two numbers The Markarian catalog lists around 1 400 galaxies active galaxies such as Seyfert galaxies and quasars galaxies that emit prodigious amounts of energy The Zwicky and Abell catalogs list clusters of galaxies These objects are not very easy to find unless you have access to an unusually large telescope These catalogs were assembled because if you study enough of them itis possible to determine information about the size and age of the universe The Zwicky catalog lists 9 134 clusters in the northern sky The Abell catalog lists over 5 000 clusters in all parts of the sky Don t confuse the Abell catalog of clusters of galaxies with the Abell catalog of planetary nebulae p 12 One can also find a galaxy by its Hickson designation The Hickson catalog lists 100 compact clusters of galaxies similar to Copeland s Septet and other close groupings The Hickson designation consists of a number from 1 to 100 followed by a letter for example 11 Hickson 42E would be the fifth galaxy found in cluster 42 The Arp catalog contains peculiar galaxies and groups of
69. ich direction around the sky An azimuth of zero degrees puts the object in the North An azimuth of 90 degrees puts the object in the East An azimuth of 180 degrees puts the object in the South and one of 270 degrees puts the object in the west Thus if Guide tells you that an object is at altitude 30 degrees azimuth 80 degrees look a little North of due East about a third of the way from the horizon to the zenith The fact that altitude and azimuth are referred to things you can actually see the horizon and the zenith makes them very useful Remember that Guide needs acorrect time and lat lon to provide correct alt az values The star you see straight overhead might not even be visible thousands of kilometers away if you don t have the right lat lon Guide may well believe itis being run in Bowdoinham Maine and has never left Project Pluto It is quite simple to find a position by alt az coordinates the process is described on page 13 APPENDIX D TROUBLESHOOTING POSITIONS At some point in the use of Guide you will not find an object at 78 its expected position This should not be too surprising Guide has a huge array of settings and if one or more is set incorrectly positions will not be as expected Check the following items EPOCH The current epoch is shown inthe RA dec Format dialog and usually in the legend By default it is set to J2000 0 the current system of choice Most galaxy catalogs and a few other
70. ick for more info on a star Several files that are not of immediate use but which may be used in updated software for Guide If so those updates will be made available on the Project Pluto Web site This includes some tide table data a list of two million place names around the world and a JPL ephemeris file covering the years 1800 to 2200 17d ASTEROID OPTIONS The Asteroid Options dialog provides some extra controls over how asteroids are shown You can access it through the Extras Asteroid Options menu item or by right clicking on an asteroid then on Display then on Options The options listed are Asteroid Labels 60 Label by number Label by number prov Label by name prov Use MPCORB Add MPC Comets Asteroids Edit Comet Data Trail length in days Line of variation in days The labelling options allow you to have asteroids labelled only bynumber bynumber or provisional designation such as 1997 XF11 the sort of designation used for asteroids that haven t been numbered yet or by name or provisional designation The Use MPCORB option is grayed out by default It allows you to switch between Guide s built in asteroid data or data from the MPCORB dataset The MPCORB file is available at ftp cfa ftp harvard edu pub MPCORB The file is available in two forms _MPCORB DAT and MPCORBCR DAT One is intended for DOS Windows the other for Unix but Guide will use either If on
71. ide while this is going on Once it s done though the chart will refresh and the image will appear If you have a dial up connection you should find that if you aren t connected at the time you click on DSS from Internet the standard Windows connection dialog should appear and dial into your ISP Insome cases this fails to happen If so you will have to make sure that you re connected to the Internet before selecting this function By default the download will be from the DSS 1 the original DSS based mostly on photographs made in the 1950s More recently STScI has been creating the DSS 2 from more recent data Both R red sensitive and B blue sensitive plates have been scanned in and you can select the sort you prefer or stick with the original DSS 1 DSS 2 was scanned at slightly higher resolution be warned that this means larger downloads Also DSS 2 is not available for the entire sky in particular asking for DSS 2 B will frequently result in an image not found message It can be interesting to first download say a POSS red image then change the Normal drop down box to read Blue overlay and then download a POSS blue image The result isn t quite a true color one and adjusting the contrast of the two images to match passably well can be difficult But it does cause strongly colored objects to become apparent 17b DOWNLOADING STAR DATA FROM THE INTERNET In recent years several new la
72. ing three days Fast moving objects will have long tails slow moving ones will have short tails This can cause objects with unusual orbits close to us highly eccentric or steeply inclined to our own orbit to stand out from the crowd of normal main belt asteroids The Line of Variation function is a very specialized option added for use by people trying to recover comets and asteroids with poorly determined orbits In most such cases the object won t be recovered exactly at the predicted position instead it will be found on a line passing through the predicted position called the line of variation LOV To show this click on the Line of Variation checkbox and set the length of the line in days a starting value of one day is usually a good idea This corresponds to a guess that the object may be one day ahead of prediction or behind prediction Guide will display a one day LOV for all asteroids and comets on the screen indicating the set of points where they would most probably be found 18 ECLIPSES OCCULTATIONS TRANSITS One of the most powerful features in Guide is the ability to make charts showing the paths on the earth cast during events where one celestial object blocks out part or all of a second object This includes events such as solar eclipses lunar occultations of 62 stars and planets occultations of stars by planets and asteroids transits of Mercury and Venus in front of the Sun and the extre
73. ion from Project Pluto The program data documentation and other items and services hereafter referred to as products provided with Guide are provided on an as is basis PROJECT PLUTO AND ITS LICENSOR MAKE NO WARRANTIES EXPRESS OR IMPLIED INCLUDING WITHOUT LIMITATION THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE REGARDING THIS PRODUCT AND THE GSC OR ITS USE AND OPERATION FOR ANY PURPOSE THE EXCLUSION OF IMPLIED WARRANTIES IS NOT PERMITTED IN SOME JURISDICTIONS THE ABOVE EXCLUSION MAY NOT APPLY TO YOU IN NO EVENT WILL PROJECT PLUTO ITS LICENSOR OR THEIR OFFICERS EMPLOYEES OR AGENTS COLLECTIVELY PROJECT PLUTO AND ITS LICENSOR BE LIABLE TO YOU FOR ANY CONSEQUENTIAL INCIDENTAL OR INDIRECT DAMAGES ARISING OUT OF OR IN CONNECTION WITH THE USE OF THIS PROGRAM AND THE GSC EVEN IF PROJECT PLUTO OR ITS LICENSOR HAVE BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES BECAUSE SOME JURISDICTIONS DO NOT ALLOW THE EXCLUSION OR LIMITATION OF LIABILITY FOR CONSEQUENTIAL DAMAGES THE ABOVE LIMITATIONS MAY NOT APPLY TO YOU 82 The liability of Project Pluto or its licensor to you for actual damages from any cause whatsoever and regardless of the form of the action whether in contract tort including negligence product liability or otherwise will be limited to 50 Project Pluto does offer a 30 day money back guarantee Return the CD and manual to Project Pluto and your money will be refunde
74. items are called mensuration measuring marks All four provide measurement of right ascension and declination just as grids on terrestrial maps provide measurement of latitude and longitude All four toggle to ON or OFF Ticks form cross like symbols chart showing where lines of RA and declination cross They basically perform the same function as a real grid but aren t nearly as intrusive Hatches are small marks on the side of the chart indicating RA dec intervals side labels are similar except that they label the mark with the RA or dec of that position A little use of all four markings will quickly make their natures apparent Select any of these four and you will see a Spacing Menu for that option This menu will look like this L Ticks on Automatic spacing declin right asc T 2s 26 xo DT 5s 57 10s 10 30s 20 7 Im 30 2m 1 5m 2 10m 5 30m 10 lh 30 2h Epoch J2000 0 Equ Ecl Alt Gal First acheck box is provided to let you turn the marking in question on or off The currently set spacings in declination and right ascension will have check marks beside them This menu lets you adjust the spacing and epoch of the marking By default the menu will show Automatic Spacing checked This means that Guide will judge the ideal spacing for the amount of area covered by a given chart using a small spacing for small fields of view and a larger spacing for large fields You will probably be content
75. ky Way in shades of gray at wide fields of view and switches to showing individual nebulae at narrower fields of view If these objects annoy you toggle Isophotes to turn them off 7a The Star Display menu The Star Display menu controls how stars are labelled and displayed You can reach it from the Display menu or by clicking on the magnitude key in the legend area the part showing what star size corresponds to which magnitude In all cases the dialog will contain these options Limiting magnitude Color Stars Outline Stars Mag Range 10 Min Star Size 0 5 Max Star Size 30 Common Names Off Bayer Auto Flamsteed Auto SAO Numbers Off PPM Numbers Off GSC Numbers Off HD Numbers Off HIP Numbers Off Yale Numbers Off Mag Labels Off 17 Proper Motion vector Non Stars On Vj Photometric band star saturation Blurring The first option is nearly self explanatory it provides a way to set the limit Guide goes to in drawing stars at the current level Some caution is necessary here If you tell Guide to draw to say magnitude 14 at a 180 degree field of view level 1 it will attempt to do so But since about 5 million stars will be drawn it will take a long time and look very messy The next two options affect how stars are drawn on the screen They are best understood by trying them When Outline Stars is turned on dim stars on top of bright stars are bordered in black making them visible This is the method usually
76. l of the items from the first Guide CD and Guide detects that the second Guide CD is in the drive it will access items from that CD The second Guide CD contains a variety of goodies that are not absolutely essential to Guide s operation but can be very helpful If Guide detects that the second Guide CD is in the drive clicking on Extras Install to Hard Drive will bring up a very different list from the one you got for the first Guide CD However as before you can select and de select items from that list right up to the point of installing all 660 MBytes or so of data from the second Guide CD Do this for both CDs and you ll add about 1 3 GBytes to your hard drive The two major items supplied by the second disk are images of deep sky objects and a detailed lunar image Some lesser items from the disk will be discussed after these By default the DSO images appear whenever you center on adeep sky object at a field of view smaller than 1 6 degrees They are displayed much asif they were RealSky or DSS images and are controlled through 59 the Extras DSS RealSky Images dialog described on page 54 Be warned that there are tens of thousands of images provided if you attempt to show all images covering say a 20 degree field of view it will take along time for Guide to show them all This is the main reason that the images are by default only shown up toa1 6 degree field of view As was discussed on page 21
77. l recenter on that object Save to Sky Comm will remain grayed out until you have entered the Telescope Control menu page 38 told Guide that you have a Sky Commander and on which port it is installed When this has been done if you click on Save to Sky Comm Guide will take the list of objects you have created and provide their locations to the Sky Commander You can then take the Sky Commander into the field and find those objects It can be useful to have a list of the objects complete with the numbers that the Sky Commander has assigned tothem To get one you can click on Output to File Windows will let you choose a file name You can store the list in an ASCII file for further use 11 TELESCOPE CONTROL MENU hotkey F4 Those with an LX 200 or Celestron telescope or a Sky Commander 38 or other encoder system connected to their computer or certain other telescope control systems can control the telescope from Guide using the Scope Control menu item inside the Settings menu Those with encoder based systems other than the Sky Commander will have to perform an alignment step and should consult the next chapter When you first enter the Telescope menu it will look like this SOMA COM2 COM3 COM4 No scope available LX 200 Sky Commander Dob Driver AltAz JMI MG III ASCOM Scope Compustar Magellan I NexStar Astro Physics Compustar Also controls over encoder resolution will be provided These are required
78. leave time unch 143718 Cor 43 43 43 minutes 18 seconds hour unchanged JD 2451 545 1 JAN 2000 12 00 32451545 same as above 2451545 same as above mjd 51000 MJD 51000 JD 2451000 5 6 Jul 2008 2008 03 14T15 26 53 5 FITS style time 2008 Mar 14 15 26 5 2008 50 or 50 2008 50th day of 2008 2008 Feb 19 50 2008 3 14 S79 same as above but sets time to 3 14 50 75 2008 50th day of 2008 18 00 050 75 50th day of current year 18 00 2008 o or Octob 2008 1 OCT 2008 00 00 00 y1952 34 decimal year near April 1952 1952 34 same as above It s best to enter the year month and day in the order you selected in the Time Format dialog Guide can always tell that 25 Oct 1987 means aday month and year in that order and will understand it even if the currently selected time format is something else But to understand 10 11 12 it has to rely on the Time Format dialog setting Months days years can be separated by or space Hours minutes and seconds can be separated by only 30 If you ve checked the two digit years box in the Time Format dialog then you can enter a year between 1940 and 2039 with just the last two digits Be warned that in this case it becomes more important that the year month and day be in the order selected in the Time Format dialog So it s probably best to continue entering all four digits of the year and to enter month names as text with that format there can be no confusion no mat
79. lection box 8 SETTINGS MENU The Settings menu lets you set such details as your position on the earth latitude longitude and altitude epoch printer and so forth The Settings menu looks like this Location Time Menu Enter Time Level 3 45 degrees Scope control Level Language Margins menu Formats TLE bright tle Projection Toolbar 29 In the Location dialog page 34 you can select your observing viewpoint so you can get data based on your actual position on the earth In the Time menu page 44 you reset the time which Guide uses for calculating planet positions rise set times and altitude and azimuth of stars In the Enter Time option hotkey Ctrl F9 you may set the time directly with the keyboard Guide is not very picky about how you enter dates and times and allows for some unusual inputs Here are some examples 1997 May 6 12 30 23 3348 6 MAY 1997 12 30 23 3348 19970506 12 30 23 3348 same as above 970506 12 30 23 3348 same as above 6 18 2004 18 Jun 2004 00 00 00 6 18 2004 same as above St LAS 59 reset time to 3 14 159 leave date a Las reset time to 13 00 00 leave date al 1172 or 117 or 1L EE 11 Feb 00 00 00 no change of year 11 2 or 11 2 or 11 2 same as above LI go 2 Same as above but 6 00 00 6d advance six days from current time 1344n subtract 13 4 hours from current time Ap April of current year tel Zo 7th of current month at 3 00 Tet 7th of current month
80. lines circles and text on top of the charts It also provides a few example overlays showing constellation borders names and outlines plus the pages in the AAVSO atlas and the plates in the Palomar Sky Survey For example you can use your own overlays to show areas you want to view in an observing session or to label some objects or points of interest or to add comparison magnitudes to achart or for any other use When you enter the Overlay menu it will look like this Edit Overlay 36 Toggle overlay on off User Object Menu When you select Toggle overlay on off Guide will list the existing overlays You can select one and Guide will provide asmall dialog box offering controls turning that overlay on or off setting its color and specifying the fields of view at which that overlay is shown For example constellation lines are by default shown in green and at fields from 9 to 91 degrees across When you re looking at a larger field such as a full hemisphere the constellation lines get crowded and in the way Below 9 degrees they cease to tell you much of anything If the overlay in question is already appearing on screen then it is usually easier just to right click on it then click Display Try this with a constellation line and you ll see that it is a much more intuitive method The only problem with it is that the overlay you want tochange will sometimes not appear onscreen perhaps because it is turned of
81. list of these catalogs click on the Open Cluster menu item Select a catalog type the number of the desired cluster in that catalog and Guide will recenter on that object Globular clusters are huge collections of up to millions of stars packed into dense balls They form a loose halo around our galaxy and around most other galaxies and contain some of the oldest stars in the universe Examples are Messier 13 Omega Centauri and 47 Tucanae Most have Messier NGC or IC numbers you can find the rest such as Palomar and Terzan objects in the Go To Globular Cluster menu The Constellation option lists the 88 recognized constellations Click on one and Guide will recenter on it You can also reach this using the gt hotkey or by clicking onthe constellation abbreviation shown in the legend area Go to TDF is used to find objects in user added datasets See page 65 Click on this option and Guide lists currently installed user datasets Click on one and enter the name of an object in that dataset If Guide can find that object it will recenter the chart on it 5a Finding stars The Star option in the Go to menu puts you in the following menu Bayer Flamsteed Yale Bright Star SAO PPM HD Guide Star Catalog Common Name Variable Star NSV Double Star Supernova DM Durchmusterung Hipparcos Nearby star In the Bayer Flamsteed option you specify a star by its Bayer letter or Flamsteed number Bay
82. lite and the field of view is so large that the object would appear as only a few dozen pixels that object is shown as a small cross mark labelled with a symbol You can change its color from the Data Shown dialog and you can click the Label planets by name option in that dialog to cause Guide to use names in place of symbols The real capabilities in how Guide shows planets only become apparent when you zoom in far enough for the object to show a disk For many objects a bitmapped surface is provided Zoom inon for example the Moon or Venus or Mars and you get a fairly realistic rendition of its surface The correct side is oriented to you phase effects are 21 shown Zoom in on Jupiter and any shadows cast on it by its moons will be apparent Right click on a planet or natural satellite and select Display and you ll get the usual controls over color labelling on off and magnitude limits for planets But when you click on the Options button in that dialog you get some finer control over how that particular object is shown Mars X X Full precision Label by name Mars X Show features Feature density 50T X Label features f Lat lon grid 30_ x __30_ degree Solid color Bitmap 1 Bitmap 2 Bitmap 3 PNN Ss ww WH Contrast Brightness Earthshine 50
83. m your own programs 24 74 Acknowledgments Appendices 76 RA and Declination Explained 77 Precession and Epochs Explained 78 Altitude and Azimuth Alt Az Explained 78 Troubleshooting Positions 79 Notes on Accuracy 80 Adding New Comets 81 Astronomical Magnitudes 82 Copyright and Liability Notices 83 List of Program Wide Hotkeys TOMO gt Index 86 TECHNICAL SUPPORT isavailable from 8AM to7PM Eastern time 13h to 24h UT 7 days a week Project Pluto 168 Ridge Road Bowdoinham ME 04008 Fax 207 666 3149 Tel 207 666 5750 Tel 800 777 5886 E mail pluto projectpluto com WWW http www projectpluto com 1 HOW TO INSTALL GUIDE To install Guide put Guide CD ROM 1 into the CD ROM drive and run SETUP from the disk You can specify the directory on your hard drive in which you want Guide to be installed You can also choose an installation language An icon indicating the shortcut to Guide will be provided and may be moved to your desktop This will usually take only a few seconds SETUP will just install a few megabytes to the hard drive enough to enable Guide torun if itcan access the Guide CD ROM You may decide that you would like to install more data from the CD or all of the CD or perhaps all of the second CD The benefits and drawbacks of doing this and how it is done are discussed on page 59 2 GETTING HELP To get help on a particular subject click on the Help option in the main menu a
84. major problem for Guide the Nebula Databank and isophotes created by Eric Sven Vesting have almost completely reversed this bad situation allowing Guide to provide accurate information and shapes for all major nebulae and most minor ones This tends to be very time consuming labor and a lot of hours were expended to check and cross reference catalogs and in extracting nebula isophotes from RealSky data The Nebula Databank and isophote data are copyrighted by Eric Sven Vesting and are used in Guide by permission The asteroid datacame from the Lowell Observatory ASTORB database computed by Dr Edward Bowell This represents a significant improvement over most past sources of asteroid data in particular the fact that it provides an indication of the precision of the orbit is most helpful The research and computing needed to generate these data was funded principally by NASA grant NAGW 1470 and in part by the Lowell Observatory endowment Thanks goto the Minor Planet Center especially to Gareth Williams for providing the MPCORB asteroid database see page 61 and the files used to patch in updated comet and asteroid elements see page 62 http cfa www harvard edu cfa ps mpc html Many of the mathematically intensive operations such as calculation of planetary and satellite positions and magnitudes precession and many related problems were solved using the methods in Jean Meeus Astronomical Algorithms Willman Bell 1991
85. mal seconds Guide will always accept input in any of these forms and will figure out which method you used and thereafter show all positions in that format 76 There is one twist on this situation If you find the latitude and longitude of a point on the Earth those values won t change significantly over time The North Pole stays under the Arctic icecap and Greenwich England doesn t move The situation is not so tidy for RA and declination as described in the following appendix APPENDIX B PRECESSION AND EPOCHS EXPLAINED If all you wish to do is to look at stars or possibly find out what that bright planet you see each night at dusk is you can probably skip this Appendix If you need fairly precise positions or wish to match a chart printed in Guide with one from another source you probably should know the following The positions of stars and planets are usually described in terms of right ascension RA and declination see the preceding appendix One difficulty with using this system is that RAs and declinations are in constant change over time The position of an object expressed in 1950 coordinates may be 7 degrees different from its 2000 coordinates The reason for this is that declination and RA are measured from the Earth and the Earth doesn t stand still The axis it rotates on slowly describes a circle in the sky completed once every 25 800 years This is why Polaris won t always be and hasn t always been
86. mely rare cases where one planet occults another In this chapter all events of this sort will be called eclipses to evade the phrase eclipses occultations and transits To show such charts there are a few steps you have to do first You need to set Guide s date and time to sometime not too long before the actual conjunction or eclipse For an example there have been numerous solar eclipses By setting the date and time you tell Guide in which event you are interested Some events of this sort are listed in Guide s Tables menu see page 50 If you just want to look at solar eclipses you can simply set the date time near that of the eclipse then hit the key But if you want to look at say an occultation of Antares by the Moon you need to right click on the Moon then on OK then right click on Antares and then click on OK By doing this you re telling Guide I m interested in seeing when _this_ object occults transits eclipses _that_ object Once you have done this the Find Conjunction and Show Eclipse options in the Extras menu will no longer be grayed out Click on Find Conjunction and Guide will pause briefly while finding the nearest or next conjunction of those two objects From Guide s point of view conjunction means closest apparent approach of the objects to each other It will reset the time and show you the conjunction of those objects If one of the objects is the moon Gui
87. n amounts in the dialog box Or if you turn off the visible passes checkbox all passes will be listed This can be helpful if for example you re considering events other than just visually looking at satellites radio communications 51 for example Create Star List is used to generate a list of stars down to a specific limiting magnitude that cover the area currently shown on the screen To use this option first find the area of interest and set the field size to cover it Select this menu option and enter a limiting magnitude If you enter say 20 you ll get all the stars in the area Guide will pause to gather data for stars in the area you ve requested that are brighter than the limiting magnitude you entered When it is done it will show you the list of stars on the screen For each star the GSC number RA dec and magnitude will be listed If the data comes from the Tycho or Hipparcos catalog numbers for that star from several catalogs may be shown the HD PPM Yale SAO and Hipparcos numbers can be listed If the data comes from the GSC then you get different data an object type code 0 for stars 3 for non stars and a plate identifier The format of the RA and dec is the currently selected one see pages 13 and 31 as is the epoch Once the list is generated you can save it to an ASCII file or print it much as you would any other help topic A few warnings about the list are in order If a star
88. n get contact times for the event as seen from that point The menus are heavily rearranged to cut out options such as star display that make sense for charts of the stars but which are meaningless for charts of the earth If the event is a lunar one or a transit of Mercury or Venus you can use the Next and Previous options at the top to search for the following or preceding event If you ve zoomed in beyond the world map level you can use Go To Country and Guide will give a list of countries Select one and the eclipse chart will recenter on that country Or you can use Go To City and Guide will list all cities in the current chart area So you might zoom in on say Australia and only then use this option to list cities in that country Select one and Guide will recenter the eclipse chart on that city Two options in the Extras menu are deserving of mention Suppose you want to know when the next eclipse visible in London is You would zoom in on that city putting it at the center of the chart and toggle the Local Events Only option in the Extras menu The Next and Previous options will then keep searching until they find an event visible from that point In the case of solar eclipses there may be a lot of partial events found in this manner So you could then toggle off the Partial Events option in the Extras menu Doing that would force Guide to insist not only on events visible from London but that
89. nd the sun and by 1582 a ten day error had accumulated 45 So in 1582 Pope Gregory declared that a new calendar would be put into effect October 4 would be followed by October 15 and certain leap days would be omitted in the future If you look at October 1582 in the Time Box you should see this odd state of affairs with ten days missing Most of the time when you see a pre 1582 date such as 10 Nov 1444 that date will be in the Julian calendar and a date such as 20 Jan 1812 will be in the Gregorian calendar By default Guide uses this Gregorian Julian system But exceptions occur Some countries notably Protestant ones didn t switch over until much later Britain and its colonies in 1752 Russia the USSR in 1918 So the Time Format dialog offers Julian and Gregorian options to force the use of one particular flavor of the calendar Dates can also be shown in several other calendars such as the Jewish Islamic and French Republican calendars It s not likely that you will wish to do that But at the end of Quick Info see page 15 Guide does give the current date as expressed in each of these calendars And if for some reason you do wish to have all dates shown using say the Persian calendar you can do so Clicking on Current Time causes Guide to look at your computer s clock and to use its date and time You can get the same effect at any point in the program by hitting the F3 key or by clicking
90. nd select Glossary The Help system is a hypertext system you can click on any term shown in blue to get the definition 2 for that term To print the help information save it to a file go back to the glossary or go back to the previous item just click the appropriate help menu item In most places in Guide you can hit Fl to get a few paragraphs describing the dialog or control you are currently using Many dialogs have a button that gets the same information 3 WHAT GUIDE IS SHOWING YOU The first time you start Guide a large area of the sky appears It shows roughly what you would see looking at the Big Dipper with the unaided eye The stars are of different sizes corresponding to how bright they appear to be from Earth There are also some lines which the sky does not show and a block of text For example a set of green lines connect the stars of the Big Dipper These constellation lines join together the major stars within a constellation They have noreal astronomical significance but help you toremember where stars and constellations are The constellations are separated by orange lines known as constellation boundaries The entire sky was officially subdivided into 88 constellations in 1930 The borders are like those of the Western United States they run the equivalent of east west and north south They provide a further frame of reference Each constellation has a three letter label shown in light blue s
91. nimating As the name suggests the horizon will now stay fixed while everything else moves stars rise above the northeast horizon In general the idea is that if you go to a particular altitude and azimuth in this case about 8 degrees above the horizon and at azimuth 45 degrees that point stays fixed while stars planets and so forth rotate by Next in the Animation menu are the Add a Trail and Make Ephemeris options The process for adding a trail may take some practice Let s take an example Suppose you would like to create a trail or an ephemeris describing the motion of Mars starting at 10 Nov 1993 and running for 100 days after that You need to make sure that the time in the Time Menu is set to 10 Nov 1993 and that your location is set correctly in the Location option in the Settings menu Then click on Mars with the RIGHT mouse button this will immediately result inthe usual brief summary of data concerning Mars When you click on a solar system object the Add A Trail and Make Ephemeris options are not gray any more you can make a trail or ephemeris for that object now If you click on a non solar system object you can t make a trail or ephemeris and these two options remain grayed out When you click on Add a Trail you ll see this dialog box Step size 10 min x Round to nearest step x Index marks Index freg 2 x Time labels on Time label freq 6 Number of steps 100 Add a Tr
92. nversion Dialog is used to adapt Guide s charts to the view seen through your telescope It can be reached by clicking on the compass symbol in the legend or through the Display menu It shows these options Chart uninverted Chart inverted Mirror image E W Mirror image N S Rotation 0 0 RA dec north at top Alt az zenith up Ecliptic north up Galactic north up The first four radio buttons let you flip the chart top to bottom left to right or both Chart uninverted says that the chart is oriented as you would see it without a telescope In your telescope however you might see something different Many telescopes use mirrors so you might see a mirror image Lenses often spin the image 180 degrees most refractors invert the image totally So do Cassegrain telescopes like the 35 popular SCT Schmidt Cassegrain telescopes Coude telescopes will invert only on one axis The next line states Rotation 0 you can use this to add any arbitrary rotation you want People with unusual telescopes might want to add a final spin of 20 degrees to their charts for example The next item tells you that North is up i e at the top of the screen So what Isn t North always up on achart Well not quite What Guide is telling you is that celestial North the direction to the North Pole is at the top of the chart Most star atlases are printed that way However as the earth turns the sky seems to turn Thus the Bi
93. o access data from the second CD ROM see page 59 Alternatively you can switch from the bitmapped views to a solid color mode where it is drawn as a shaded single colored sphere This option is considerably faster than the bitmapped options and for many smaller satellites that lack a bitmap it s the _only_ option Using the slider bars you can modify the brightness and contrast used for the planet bitmap Set Earthshine to 0 and parts of the Moon and other objects that are not in sunlight will appear black Set it to 100 and they ll appear as if fully illuminated and none will show phases You usually want something bright enough that you can make out features on the dark side but dark enough that you can tell which side is illuminated at a given time For some special project you may decide you want a very dark setting for realism or a100 setting for use in an atlas mode 7d The Camera Frame menu When you toggle the CCD Frame in the Display menu Guide puts a rectangle on the screen You can set the size position and tilt of the rectangle This may be used to show the area covered by a camera or CCD image A dialogue box will now appear with the items Show Frame Center Frame Angle Focal length Camera name Spin Left Spin Right Show Pixels Guider Range Banning The first item simply toggles between showing and not showing the frame The Center Frame check box causes the CCD frame to remain
94. o is almost always to just click on it with the right mouse button You will get a small dialog box describing that object and a Display button Clicking on this will lead you to the controls for that type of object For example right click on a 19 galaxy then on Display and you can adjust such things as the limiting magnitude for display of galaxies This is an immensely simple and powerful way to deal with objects that are being shown on the screen But if galaxies for example are currently turned off you re obviously unable to click on one in order to turn galaxies on In such cases you need to use the Data Shown dialog It s also convenient if you want to change the display of many types of object at once In the Data Shown dialog you are given a list of fifteen classes of objects controlled by the Data Shown menu dialog Messier NGC IC Galaxies Nebulae Planets Variables NSV Open clusters Asteroids Gal Clusters Comets Globulars Planetaries Dark Nebulae Satellites Each object class is followed by buttons to turn that class on off auto or fixed When a particular class of objects is turned On all objects of that class will be shown regardless of magnitude When Off none will be shown When set to Auto or Fixed all objects brighter than the magnitude limit for that class will be shown The difference between fixed and auto is a simple one In auto mode Guide will autom
95. omewhere within the constellation bounds For the Big Dipper it is UMa Ursa Major or The Great Bear The Great Bear is usually shown with the Dipper serving as its tail Seeing the rest of the Bear or of most constellation figures requires some imagination Many of the stars have Greek letters attached to them This shows the most common way of naming the brighter stars letter plus constellation name Thus the star at the end of the tail of the Great Bear can be called Eta Ursae Majoris The added is is a Latin version of belongs to These letters are called Bayer letters after the astronomer who first assigned them Usually but not always they are in order of brightness within a constellation i e Alpha is brighter than Beta which is brighter than Gamma In Guide there is a fairly general way to adjust the display of any of these objects when they appear on screen If for example you found the constellation lines to be objectionable and wanted to get rid of them or change their color you would click on one of them with the right mouse button You will immediately get a short bit of information about the object you clicked on which can help in what in the world is _this_ situations But the dialog box with that information will also have a Display button clicking on this will give you a chance to turn that class of objects on or off or change its color and sometimes adjust magnitude limits and labelling Al
96. ons Show Time through Hour Angle are toggles controlling whether an item will be put in the legend If you re producing charts showing an eclipse the time and lat lon are important items that should appear on the chart If the chart shows how to find the Double Cluster however the time and lat lon are irrelevant but the RA and declination should be shown In the display you can click on many of the legend items to change them or to cause some related action For example if the time is shown in the legend left clicking on it will bring up the Time dialog and right clicking on it will set the time to the present Clicking on the RA will bring up the Enter new RA dec box clicking on the galactic coordinates will bring up a box to enter galactic coordinates for the chart center and so on Tooltips are provided for all of these but in a somewhat unusual place on the application title bar When you turn the Second Time option on Guide will ask you to select a time zone The legend will then contain the usual time but will also show you the second time in a different zone This can be used to ensure that for example the legend shows the time in UT but that you can still have the local time shown for reference or perhaps the local sidereal time or some other time zone Sidereal time isn t normally thought of as a time zone but treating it in this manner can be useful The caption refers to text you may wish to
97. oon or other planets The view of the inner moons of Saturn as viewed from Japetus is particularly recommended This can be very interesting and educational although most Guide users cannot physically travel to other planets or to near Earth orbits Most Guide users can set their viewpoint on the Earth with the Enter location name button Click on this and enter the name of your city or town and Guide will usually figure out the corresponding latitude and longitude In the US this can be a name plus two letter state abbreviation Augusta ME or Houston TX or it can be a five digit postal ZIP code such as 04008 Outside the US it can only be aname and unfortunately the number of recognized cities is not very great So most people will have to enter a latitude longitude position This can be found on most maps or with aGPS receiver You usually do not need to be nit pickingly precise about this Guide uses your place on the earth to calculate rise and set times and to get better accuracy on planetary positions For example a solar eclipse visible on one part of the earth may not be visible at another because the moon isn t exactly in the same spot in the sky An accuracy to a degree meaning about 111 kilometers or 70 miles will get rise and set times to within about four minutes But if you want to get good positions for artificial satellites or times for eclipses and occultations you will want an accuracy of at lea
98. ordinates Entering ecliptic coordinates For grids tacks etc Shown in legend Shown on screen Encoders Ephemeris generation Control over data shown Epoch Definition Resetting Resetting for markings Equation of Time ESO galaxy catalog Fixed levels Flamsteed numbers Definition amp finding by Turning on and off Flashlight mode Fonts Galactic coordinates Entering galactic coordinates Shown in legend For grids ticks etc Galactic equator display Galaxies Displaying labelling Finding Globular clusters Glossary Great Red Spot Lists of visibility Greek letters Gregorian calendar Grids Guide Star Catalog GSC Accuracy Definition Displaying numbers Finding by number Non stars 87 50 See Bayer letters 45 26 19 72 17 J L9 Hatches HD Henry Draper Catalog Displaying numbers Hipparcos About the catalog Finding Displaying numbers HR Yale Catalog see Bright Star Help Hotkeys Horizon display Horizon menu Horizon objects Hour angle display in legend HR Catalog See Bright Star Index Catalog IC Installation initial Installing more data Inverted flipped charts Isophotes Jovian events Julian calendar Julian day JD Language Languages adding new Latitude LEDA Legend Librations Line of variation Location dialog Longitude Lunar phases LX 200 Lynd s Bright nebulae Lynd s Dark nebulae Marks Deleting mark files Magnitude Margins for printing Markarian galaxy ca
99. ou ll see an option there to clear all the stars from that catalog 57 All of the Internet downloaded catalogs are implemented as user added datasets You can go into Extras User Added Datasets click on for example 2MASS data downloaded from VizieR and see the controls over that dataset Of course you may well wonder what each of these catalogs are Each has strengths and weaknesses in terms of accuracy number of stars contained and the sort of data given for each star The USNO A1 0 and A2 0 catalogs are the eldest of this group dating back to 1997 A2 0 is an update to A1 0 with recalibrated improved magnitudes and positions but they are frequently lumped together as Ax 0 As was mentioned earlier this dataset was distributed on CD ROMs how to use those CDs with Guide is the subject of the next subchapter The Ax 0 catalogs list about a half billion objects Objects were found by scanning in wide field photographic plates some of them dating back to 1950 Usually two plates one red sensitive and one blue sensitive were used This means the catalog can give an indication of the object s color not always a very accurate one though and that many spurious objects could be safely ignored if an object was found on only one plate it was assumed to be an error or a flaw in the plate or a passing asteroid or satellite In this catalog and in B1 0 and GSC 2 3 the magnitude data is of mediocre accuracy USNO was
100. ould turn the aperture on 27 and set that size The resulting circle would let you see how much of the sky is visible at a given time with that telescope eyepiece In entering the aperture size you can also enter 15 for a 15 arcminute circle or 45 3 for a 45 3 arcsecond circle Also when any of these objects appears on screen you can adjust its display by right clicking on it then clicking Display The only time it is truly necessary to go through the Ticks Grids Etc menu option is when the object type you want isn t on screen perhaps because it is turned off 7g Background dialog In the Background dialog inthe Display menu you may modify the usual white stars on ablack background appearance of the screen There are five different types of background normal colors chart mode red mode flashlight mode and realistic Normal Colors is the default the background is usually black Printouts always have black stars on white even with color printers Chart Mode switches toa white background This was first added to support color printing Ifyou have acolor printer you can switch to Chart Mode set colors to match what you want to see printed and then do a printout It would be very clumsy to set up colors if you didn t have a way to turn the screen background to white It has turned out to have other uses however and some people prefer it to normal mode The Red Mode option converts eve
101. ows about it You can also export that 13 information to an ASCII file for use in a word processor or other software or simply print it directly For example suppose you centered on the star Acubens You could do this by clicking on Go to then Star then Common Name and finally on the name Acubens or just hitting Ctrl B and entering alp cnc or Acubens Click on Acubens with the RIGHT mouse button A dialogue box will pop up in the center of the screen It tells you that this star is called Acubens or Sertan that it has Bayer letter Alpha Flamsteed number 65 in the constellation Cancer It gives some rise set times its number in several catalogs and its magnitude Magnitude or brightness level is discussed on page 81 Finally four buttons are shown labelled OK More Info Next and Display Click on the OK button and the information will vanish Click on Next and Guide will return information about the next nearest object This can be handy in crowded areas or with overlapping objects where your first click may not get the desired object in such cases you can click Next until Guide finds the object you really wanted Clicking on Display leads to controls over the display of a given type of object Since you right clicked onastar clicking on Display here would lead tocontrols over how stars are displayed their magnitude limits how they are labelled and so on If you had instead right cli
102. pole right now the South Pole has no such luck and at many times in the past no bright star has been near the North celestial pole either There are many ways to zoom out you may for instance hit lt gt _ the divide key You will then see an area of the sky roughly twice as large in both height and width Because you see more sky some markings will be dropped out to avoid cluttering the screen for instance the Bayer letters are now omitted To zoom in hit lt gt the asterisk You ll see the reverse of the Zoom Out process occur The asterisk and division keys can be used at any time and at any level in the program they are program wide hotkeys A list of program wide hotkeys is found on page 83 If you have a three button mouse you can click with the center mouse button to combine recentering on that point with zooming out one level Usually whenever you zoom in or out Guide tries to decide what level of clutter you would like best Stars will brighten or dim as you zoom in or out and dim stars will drop out as you zoom out and appear when you zoom in You can override Guide s judgment through the Display menu From Level 2 you can zoom out one more level This takes you to a point where you see half of the entire sky and only the brightest stars You can keep on zooming in to Level 20 though there is usually not much to see past Level 10 or so because the stars only 4 go to about magnitude 14 or 15 The deeper l
103. projecting it onto the sky On Earth latitude is a measure in degrees of how far one is from the equator Thus the north pole is at 90 degrees the south pole is at 90 degrees This translates readily to the concept of declination in the sky Polaris the North Star is at close to declination 90 You can express adeclination as you would any angle in decimal degrees in degrees plus decimal minutes of arc or in degrees minutes and decimal arcseconds The format Guide uses in displaying declination and RA can be specified see page 31 RA is similarly analogous to longitude The celestial version of the Prime Meridian is the Sun s location at the vernal equinox the place where itcrosses the celestial equator near 22 Mar RA is measured from this point all the way around the sky until the vernal equinox is reached again There are two key differences between RA and longitude In the first place longitude is usually measured from 180 to 180 degrees RA is never negative it s similar to measuring from zero to 360 degrees which is how some people do measure longitude The second difference is that instead of being measured in degrees RA is measured in units of time The entire distance around the sky is not 360 degrees but one day A fraction of this distance can be measured in hours minutes and seconds As with declination this can be either decimal hours hours and decimal minutes or hours plus minutes plus deci
104. re are some additional buttons below these that are specific to computer control of a scope Slew Scope is used for aiming the telescope If you have found and clicked on a location in Guide hitting Slew Scope will slew the telescope to that location You can also do this by hitting F11 or Ctrl F1 at any point in Guide For the JMI MG III_ based systems there are again no motors to move the telescope In this case a red indicator appears on the chart to show where the telescope is pointed and is updated every second or so Clicking on Slew Scope again will shut off the display of this indicator The Slew Guide option will cause Guide to find out where the telescope is pointed Guide will then pan to that location leaving the telescope where it is You can also do this by hitting F12 or 40 Ctrl F2 at any point in Guide Also if you have toggled to the Sky Commander and have selected its port you can copy a list of positions from Guide to the Sky Commander You can then take the Sky Commander into the field and observe those objects This is further described in the section on the User Object menu on page 38 One note about the Alt Az system This button corresponds to a stepper motor system designed by Mel Bartels and used by several Dobsonian owners The advantages ofthe Alt Az system are simplicity good precision and very low cost The system consists of stepper motors added to the altitude and azimuth axes and d
105. re that this is far from a perfect system mostly because the data is far from perfect GSC stars and stars from most user added datasets are unaffected by your choice of magnitude system because the data simply doesn t exist In other cases for example when computing Ic Cousins infrared magnitudes Guide has to estimate a magnitude using for Tycho stars VT and BT data The result is usually in the right area but shouldn t be relied upon for precision work If you select Color stars Guide defaults to showing them with very bright saturated colors Red stars are fire engine red yellow stars are canary yellow and so forth Of course stars actually appear visually to have much milder colors You can replicate this effect by changing the saturation value It defaults to 100 full color saturation Turn it to say 50 and the stars will appear to be somewhat more realistically colored The blurring option is another gesture toward realism Set it to a non zero value and Guide will draw stars with softer edges making them look a little more circular A value of 1 to 3 is usually considered visually pleasing As with many of the settings in this dialog though your personal preferences may be very different 7b The Data Shown dialog First a very important tip if you see an object on the screen and wish to turn it off or change its color or change the fields of view at which it is displayed the simplest thing to d
106. rge star catalogs have become available In general these are more accurate and detailed than the GSC ACT used by Guide The options to access these catalogues are in the Extras Get Star Catalog Data submenu Get A1 0 from CD ROM Get A2 0 from CD ROM Get A2 0 from Internet Get B1 O from Internet Get 2MASS from Internet Get GSC 2 3 from Internet Get UCAC 2 from Internet 56 Get CMC 14 from Internet Clear Ax 0 Data The A1 0 and A2 0 catalogs were originally distributed on CDs A1 0 consumed ten disks A2 0 eleven If you have these disks you can zoom in on an area of interest then click on Get A1 0 or A2 0 from CD ROM Guide will prompt you to insert a particular Ax 0 disk into the CD ROM drive do this and it will extract data covering the current area shown on screen then ask you to put the Guide CD back in If you re running Guide from the hard drive as described on page 59 you can ignore that message A2 0 consumes a total of 6 3 GBytes which is not much on a modern hard drive If you have copied part or all of Ax 0 to your hard drive then Guide can display it without going through the Extras Get Ax 0 from CD ROM menu Inthis instance Ax 0 will simply be shown on the charts in the same manner as stars from any other catalog To do this you need to edit the file GUIDE DAT with atext editor such as Notepad and add a line such as this A2_ PATH 14 3 c a2 The above line would tell Guide that if it s
107. riven by the PC All of the intelligence for alignment etc is in the Alt Az software making for very minimal hardware requirements If you have an interest in connecting your own customized computer controlled telescope to Guide you may wish to check the file COMPRESSXTROL DOC on the CD ROM It contains some data on how communication with LX 200 and ALTAZ systems is done by Guide lla Encoder based systems As was mentioned above handling alignment of JMI MG III type systems Tangent Instrument boxes isasomewhat different process from that required for other systems The other systems have built in hardware tohandle alignment Tangent Instrument boxes require Guide to handle that task To use your JMI MG III compatible encoders hook up the interface to the computer start Guide and click on Settings Telescope Control Select the serial port used for the encoders this is usually COM2 but itmay be COM1 on some laptops And in some odd cases it may be COM3 or COM4 Also select the JMI MG_ III radio button and enter the scope resolution in the boxes at the bottom of the dialog Click OK After a short pause Guide will provide a Scope resolution successfully set message and will add the Scope Pad option to the menu bar If it shows any other message then Guide has been unable to set the encoder resolution correctly Check the encoder connections and make sure the COM port has been set up correctly If Guide su
108. rmal mode with stars bright and the background dark Click on Invert images and they will be shown in a photographic negative mode with the background bright and the stars dark If you ve extracted large numbers of images from CD ROMs you may want to free up the hard drive space they consume Clicking on Clear RealSky Images will do this You ll get an are you sure message and if you confirm the images will be deleted Toextract RealSky DSS images from CD ROM you should first center on the area of interest then click on RealSky DSS from CD You ll get adialog box in which you can tell Guide abit about what size image you want and whether you want toextract itfrom DSS or RealSky North or RealSky South CD ROMs There may be more than one scanned image covering the region you re interested in if so you can select the one you want to use Though in general you ll just want to accept the default image You ll be asked to insert a given CD ROM and the image will be extracted from it After this you ll be asked to put the Guide CD back in the drive and Guide will draw achart with your newly extracted image shown Add DSS Image can beused toimport aDSS image you ve downloaded manually from the Internet You ll normally want to use the DSS from Internet option described below but there are still some holdouts who prefer to get DSS images from various servers then import them to Guide using this function The ser
109. roids are therefore also unlabelled asteroids and are simply shown as cross marks For the Planets there is a panel with two switches Full precision and Label by Name The first toggles between normal precision the default and full precision for positions Planet positions are calculated using either the VSOP Variations Seculaires des Orbites Planetaires theory or the PS1996 theory both compiled atthe Bureau des Longitudes in Paris In each theory planetary positions are calculated as the sum of a long series of trigonometric terms When full precision is used all terms in the optimal theory are used and planetary positions are precise to roughly 01 arcsecond Computing them can be slow on older computers If you have a more modern computer you will probably not even notice the slowdown Normal precision provides a precision of about an arcsecond over the period 0 AD to 4000 AD Itis based on VSOP but omits many of the smaller terms It is the truncated version used in Jean Meeus _Astronomical Algorithms_ Willmann Bell 1991 For normal use arcsecond precision is more than sufficient but there are cases where the additional level of accuracy in full precision is truly necessary Italso allows Guide toclaim higher accuracy than other software Those wanting specific details of Guide s accuracy should look here http www projectpluto com accuracy htm 7c Planet display When Guide shows a planet or natural satel
110. rom the keyboard This would for example be the fastest way to go from 1985 to 333 When you enter an hour you can also reset the minutes by entering something like 3 14 or you can reset the hours minutes and 44 seconds with something like 3 14 16 Historians and astronomers differ in how they write years before 1 AD Historians do not use a year zero To them the year before 1 AD is 1 BC Astronomers say that the year before 1 AD is 0 and the year before that 1 This causes a one year difference if astronomers say an eclipse occurred on 28 Aug 1203 historians say it happened on 28 Aug 1204 BC Since Guide is an astronomy program it sides with the astronomers recognizes the year 0 and expects 1203 to be entered in the above instance You can click on the days shown in the calendar for the current month plus the usual partial calendars for the previous and following months shown in the next six lines This is a fast way to back up or move ahead a few weeks The Time Zone UTC option lets you tell Guide what time zone you are using By default Guide displays all times in UTC Coordinated Universal Time basically Greenwich Time but clicking on this option brings up a long list of the world s time zones You can also select time zones such as Greenwich sidereal time local mean time Dynamical Time etc These are not really time zones but selecting them means that Guide will display all times in those system
111. rough the MPC say from an article or elements for a theoretical object then you will have to enter the elements by hand using the Edit Comet Data function Here s how to do this First some background on how an orbit is defined Usually five or six figures called orbital elements are needed When you click for more info on a comet or asteroid in Guide these elements are among the information listed 80 Orbital elements can be expressed in a variety of ways Usually a comet s elements consist of a time of perihelion the time it comes closest to the Sun represented by a capital letter T the distance from the comet to the Sun at the time of perihelion or q the orbit s eccentricity a measure of how stretched out the orbit is a value of 1 or greater means the comet won t return or e the longitude of the ascending node represented by an uppercase Omega looks like a horseshoe the inclination or i and the argument of perihelion represented by a lowercase omega looks like a curly w These last three are angles that define how the orbit is oriented in space Asteroid elements usually replace the time of perihelion with an epoch time and a mean anomaly an angle defining the object s position along the orbit at the epoch time Also the semimajor axis a is sometimes used in place of the perihelion distance The Edit Comet Data function in the Asteroid Options dialog box will provide a list o
112. rything in the chart and many controls outside the chart to shades of red and black This can be significantly less damaging to dark adapted vision and is acommon choice among people running Guide in the field If you run Guide in the field without using this option your eyes will never fully adapt to darkness and you won t see as much in the sky as you ought to By default red mode is indeed red But you ll see a button provided with that default shade of red and can click on it to select abrighter or dimmer shade of red Or you can choose a different color there is a school of thought that holds that a dim shade of green is really the best color for _ preserving night vision In Flashlight mode the background is red and markings are black The result is a bright screen that won t damage night vision It is sometimes useful in finding dropped eyepieces and such you can switch to flashlight mode find the missing object and switch back to red mode Of course most people will use a real flashlight with a red filter for that purpose Realistic mode shows a bright blue sky in the daytime and a dark black background atnight Between sunset and true night when the sun is more than 18 degrees below the horizon shades of blue denote the 28 progress of twilight This gives you some clue to the visibility of an event if you set Guide to show for example a lunar occultation and the background turns bright blue you can rea
113. s or AVI files To do this set up Guide to show the sky as you wish in terms of location date time objects displayed screen size etc You ll probably want to resize the screen to make it smaller since a full screen animation results in tremendously large files Click on the Make an AVI option in the Animation menu Guide will ask you to select a file name then a compression method The compression methods available will depend on what happens to be installed on your hard drive as part of Windows After that each time Guide draws a chart that chart will be added as a frame of the movie So you can bring up the Animation dialog box and start animating as you normally might do perhaps following the motion of a particular object While the animation is proceeding you can stop switch to different objects change the animation step size and so forth When you ve completed the animation go back into Animation and toggle off Make an AVI Guide will close the current animation file and you can view it with Windows Media Player or any similar AVI aware utility 16 THE TABLES MENU The Tables menu contains the following options Lunar data Lunar phases Lunar apogee perigee Lunar eclipses Solar eclipses Current comets Current asteroids Jupiter events GRS transits List planet features List satellite passes Create star list Miscellaneous tables Each option allows you to make atable of data which can be vi
114. s and will expect times you enter to be in those systems The zone you select need not match the one used by your computer s clock If you wish to have Guide show times in UTC even though your PC clock is set to a local time zone this is not a problem The JD option lets you both see and reset the Julian Day The Julian Day system no relation to the Julian calendar is in common use by astronomers it specifies time in terms of days since noon Jan 4712 BC Thus 1 Jan 2000 is JD 2451545 that is how many days will have elapsed since 1 Jan 4712 BC As you alter the time the value shown here will change and if you click on it you will be asked to specify the time by Julian Day The Time Format option lets you choose how dates and times will be shown throughout Guide You can decide if dates should bein YYYY MM DD form orMM DD YYYY form orperhaps Julian Day form or given in decimal hours or decimal days instead of the usual hours minutes seconds form You can also choose to have dates shown in any of several calendars the most important of these are the Julian and Gregorian calendars The Julian calendar is unrelated to the Julian Day system confusing though that is The Gregorian calendar is the one currently used in most of the world The Julian calendar was its predecessor and is almost exactly similar Unfortunately its leap year rules resulted in a year that didn t quite match the earth s actual motion arou
115. s can be extracted and their display controlled This is discussed in detail starting on page 54 Get Star Catalog data provides some options to access several truly immense star catalogs and to control their display This is discussed starting on page 56 Asteroid Options provides control over how asteroids and comets are displayed You can also reach it when you right click on an asteroid then on Display Options It is discussed on page 60 By default Guide works on fixed levels for example one goes from a field of view of 20 degrees at level 4 to one of 10 degrees at level 5 with no intermediate step You can t access a level 4 5 15 degree field of view the best you can do is to change level 4 or 5 to be equal to 15 degrees using the Set Level Size option in the Settings menu p 31 The way to get around this clumsiness is to turn Fixed Levels off When you do this dragging abox open on the screen lets you choose a continuously varying field of view instead of jumping from one level to another You can still go to level 4 to get a 20 degree field of view and other aspects of zooming in and out are unaffected The only real change is that you can get those intermediate fields of view The Toggle user datasets opton is slightly misleading In reality Guide already contains anumber of datasets in the user dataset system including catalogs of galaxies quasars radio objects nearby stars the Palomar surve
116. self is of the sort common in Guide the object is specified with a tilde plus the object identifier and then text is given for that object 21 Adding your own notes for objects Not many people will have aneed to add their own datasets except for some special purpose projects Amore common wish is to add some comments for an object If you know how to use a text editor this is quite simple to do For example let s say that you have just observed NGC 253 and would like to make some notes on what you saw Go to your text editor and edit the file NGC NOT in your Guide directory You ll see that a few notes have been added already mostly telling you what supernovae have appeared in which galaxy This is admittedly not very crucial data it s supplied mostly to give an idea as to how the system works You ll also see that some notes have already been supplied for NGC 253 Try extending that text to read something like 253 The supernova 1940E was found in this galaxy on 1940 Nov 22 at RA 00 45 1 declination 25 34 epoch B1950 magnitude 14 0 On 23 Aug 1997 I observed this galaxy with a 10 f 4 Newtonian and saw that Of course you can add remarks for new objects by inserting tilde number s for them There are similar files for a variety of other objects IC NOT UGC NOT ASTEROID NOT and PLANETS NOT The system has to be modified in cases such as 71 COMET NOT and PK NOT you ll see that these files us
117. set any further If you have a lot of datasets each covering a small area such as the sections of the 6C radio survey this can speed matters up substantially The ralimit field is unusual but the declimit one is not For example most datasets created in the Northern Hemisphere have a southern declination limit except for neutrino based observations 20c Adding More Info and click data for your dataset You will notice that each dataset also has a few lines starting with a tilde followed by c r or b Each of these lines involves showing some data when the object is clicked on when you get remarks more info or both respectively After the letter two numbers are given the starting column and length as was true for most of the fields already discussed Guide first checks to make sure that this field is not blank If it is indeed not blank Guide shows that field using the remainder of the line to decide what the format should be For example the following line from the quasar dataset r46 5 Color index B V s tells Guide that the quasar dataset stores color index data in columns 46 50 If Guide finds data in those columns this is not a given since not all quasars have had their color indices measured then Guide will show Color index B V the color index and then skip to a new line that s what the means Because this is a r line Guide will only show this data in
118. showing stars fainter than magnitude 14 3 it should show A2 0 stars If the current magnitude limit is brighter than this there is probably not much point in showing the Ax 0 stars It also tells Guide that the Ax 0 files can be found in the a2 directory of the C drive Once you have done this you can ignore the Get Ax 0 from CD ROM and Get Ax 0 via Internet options because the Ax 0 stars will simply pop up automatically when you get to a faint enough magnitude limit As the catalogs became larger distribution on CD ROM ceased the remaining catalogs are only available via Internet You must first zoom in to the area for which you want data then click on any of the get star catalog from Internet options and Guide will make a request of the VIZIER astronomical data server at the University of Strasbourg in France for data covering that area After a pause to download the data the screen will be redrawn with the new star catalog data shown As with most objects shown in Guide you can then right click on any of the downloaded objects to get information about it and get more info or click on display to get control over how that catalog is displayed the fields of view at which it is shown whether catalog IDs are shown as labels for each object the color used and the limiting magnitude used Downloads of each of these datasets accumulates If you want to clear the data right click on an object then on More Info Y
119. sic idea is apretty simple one Most databases are in plain ASCII text or FITS files with data arranged in columns Guide will absolutely need to know certain basic things about the database such as which columns contain the RA hours data which the declination minutes the file name of the database the epoch of the coordinates and so on All of this information is stored in a Text Definition File TDF Four examples are provided in your Guide directory CD_DATA TDF CD_DATA2 TDFCD_DATA3 TDFan amp ADIO TDFEaclontainslefinition data for several datasets on the Guide CD More are posted from time to time on the Project Pluto Web site Unfortunately the TDF format is quite Guide specific because there are no real standards in this area FITS files were a possible standard but are despite the name far from standardized are hard to edit using standard text editing tools and lack many useful features One can freely add new TDF files Guide will automatically detect them and display the data defined by them You can move datasets freely from one TDF file to another or combine them all the default four TDFs just made dataset management a little simpler If you edit either TDF file with a text editor the format used will probably be quite clear There are a lot of fine points to be considered though as you will see on the following pages As you can see each dataset in a TDF file starts with two lines such as file adio
120. sizes that look wonderful on screen are less appealing on the printed page and preferences as to star size vary widely 13 Postscript charts The Extras menu of Guide contains a Make PostScript File option PostScript charts can be imported directly into some desktop publishing packages Because they are vector not bitmap files they can be more easily edited Also people running Guide under DOS and OS 2 sometimes have found that making a PostScript file then printing it using GhostScript produces particularly good charts and can be faster than the usual DOS or Windows printing The standard Windows driver for PostScript printers is abysmally slow People with PostScript printers can simply copy the files to their printers to get high quality output To make such a chart you should first follow the normal steps required for printing setting margins making sure the right part of the sky is on the chart and that the objects you want are turned on and so forth But then instead of clicking on Print use the Make PostScript File option in the Extras menu Alternatively you can hit the Alt P hotkey In DOS you ll be prompted to enter a filename in Windows adialog box will be shown from which you can 43 select a filename or enter a new one Enter or select a filename and Guide will write a PostScript file to it In part because PostScript has better font technology charts created using PostScript tend to ha
121. so there is a legend at the lower left corner of the chart showing the position of the cursor the constellation you re in the sizes of stars for different magnitudes and some other data As you move the cursor the position readout will be updated Clicking on most of the items in the legend will allow you some sort of control over Guide For example click on the constellation shown in the legend and Guide will let you choose a constellation on which to recenter the chart Clicking on the hours shown in the time in the legend adds or subtracts one hour from the current time used by Guide adds an hour for a left click subtracts an hour for a right click As you move the mouse over the legend Guide s title bar will tell you what action a click on that point would do 4 PANNING AND ZOOMING To move to another part of the sky you can move the mouse cursor to somewhere else on the chart area and click onthe LEFT mouse button A chart will be drawn at the same scale but centered at the point you clicked on Click on the center of the top of the chart and you will see a smaller version of the Big Dipper with its brightest star at the tip of the handle This is Ursa Minor the Small Bear or Little Dipper The bright star is the North Star Polaris The arcs of the constellation boundaries center on well very close to this star it marks the celestial the North Pole It s only coincidence that gives us a fairly bright star near the
122. sonably expect not to see that event Finally there are two check boxes for Show Ground and Horizon Objects The first causes the ground to be shown in a solid color Again this can be useful for determining if an event is visible if you turn Show Ground on and the event in question is in the ground area you know you won t be able to see it With Horizon Objects turned on Guide displays afew objects at the horizon such as trees houses cars streetlights and so forth This can provide a certain sense of scale It s also possible to rearrange these objects and add new ones see the instructions in the files HORIZON DAT and OBJECTS DAT for details Some people have done this in order to get a horizon that matches their actual observing site This helps in planning observations you can get a better idea when the moon will rise from behind a certain hill and in orienting yourself properly Unfortunately figuring out the azimuth to the objects in question can be a bit of a challenge You can use a compass or you can observe a star pass over an object at a given time then use Guide to determine the altitude azimuth of the star at that time By default the background is white in Chart mode and black in Normal Color mode and the ground isabrownish red color However three buttons are provided in the dialog box to adjust this Each is a blank rectangle showing the color in question click on one and you get a color se
123. sources are still in B1950 0 coordinates The difference can be of the order of half a degree LATITUDE LONGITUDE An object viewed from Texas will not be found in the same position as seen from Brazil The difference is usually small but some objects come close enough to the Earth for it to matter Your altitude above sea level set in the Location dialog in the Settings menu has a similar but much smaller effect While in that dialog you should also check your HOME PLANET see page 34 If you are observing the Solar System from say Venus objects will obviously not be in the same place as if they were observed from Canberra Australia Non solar system objects are not affected The parallax effect is ignored for them The Moon can be shifted by up to 2 degrees if the wrong lat lon is used Asteroids and comets passing very near to the Earth can be still more seriously affected Planets are usually not affected by more than a few arcseconds TIME If the time is 13 days off from its expected value make sure you are using the Gregorian calendar Check the Time Zone setting Remember that Guide uses a 24 hour clock 8 13 PM becomes 20 13 This is one reason it s a good idea to have the time and time zone displayed in the legend area as they are by default Finally it s worth considering the precision of the source used for the expected value Perhaps the most common source of error is the assumption that some software
124. st one kilometer Systems of latitude and longitude are also defined for other planets The center of the visible side of the moon as seen from Earth is 34 defined to be at latitude 0 longitude 0 If you select Luna as your home planet and set those values the Earth will be shown very near the zenith It wanders a bit around that point due to librations as described on page 15 The next item Alt 100 meters tells you that your point of view is 100 meters above sea level Once again you need usually be only approximately correct here Clicking on the Use geocentric position causes Guide to ignore the lat lon altitude values instead your viewpoint will be from the center of the earth or whatever home planet you have selected The final four options only have meaning if your home planet is Earth and the geocentric option is not selected i e you are observing from the surface of the earth Set the Include refraction button and refracted altitudes will be shown in the legend and when right clicking on objects whenever the altitude is above the horizon In general including refraction doesn t make a very large difference about an arcminute or so except for locations very close to the horizon The temperature humidity and pressure data are used to compute the amount of refraction All three values are used in computing the limiting visual magnitude in Quick Info see page 15 8b Inversion Menu The I
125. steroids New comets and asteroids are always being discovered and in some cases new observations allow the precision of existing orbits to be improved Guide will be fairly up to date on comets when you receive it as new ones are discovered they are added to COMETS DAT Guide will also show some future comets such as Halley in 2061 and P Swift Tuttle s next return in 2126 because these comets were observed carefully when last visible and their future orbits computed However new comets will be discovered after you receive Guide usually a few are found each month and you may want to display them in Guide If you have access to the Internet the easiest way to get up to date orbital elements for comets is to download them from the Minor Planet Center MPC Web site You can use the Extras Asteroid Options dialog then click on Add MPC Comets Asteroids and then use Click to download updated comet data and add it to Guide This method guarantees good current data and removes the need to understand orbital elements The amount of data downloaded only about 35 KBytes so it s quite fast even over dialup You can replace Guide s built in set of asteroids using the MPCORB dataset This is described on page 61 The only problem is that the download is quite large over 20 MBytes but this is hard to avoid there are simply a lot of asteroids out there If you lack Internet access or if you want to add elements not available th
126. suffers a bit from the extra compression The CD ROM versions of both DSS and RealSky are distributed by the Astronomical Society of the Pacific ASP DSS RealSky Images leads to a dialog box offering controls to extract images from the CDs or download them from the Internet and to control how they are shown Some of its controls also apply to a collection of images of deep sky images available on the second Guide CD ROM these are discussed on page 59 The dialog box looks like this DSS RealSky Images X x Show images Show at 0 1 6 Invert images Clear RealSky images RealSky DSS from CD Add DSS image DSS from Internet DSS downloads lt DSS 1 gt lt Normal gt OK Cancel Ifyou have some images shown on screen and would like to temporarily disable them you should uncheck the show images checkbox Noimages will actually be deleted but they won t be shown until you turn the checkbox back on 54 As with many other objects shown in Guide you can use show at to tell Guide only to show the images at certain fields of view By default images are shown only between zero and 1 6 degree fields of view They don t tend to look like much of anything above 1 6 degrees and there can be so many images at larger fields of view that the program drags to a stop while drawing them By default Guide will show images in no
127. t will also give the limiting visual magnitude for the currently centered part of the sky for the currently set time using a method described by Bradley E Schaefer in the May 1998 issue of Sky amp Telescope 7 DISPLAY MENU The Display Menu controls what is shown by Guide and how it is displayed This menu shows the following items Star Display Data Shown Legend CCD Frame Inversion Menu Ticks Grids ECO Screen font Printer font Direct to screen Background Isophotes The Star Display option page 17 brings up a dialog box with controls over how stars are labelled their sizes and whether they are colored by spectral type The Data Shown option page 19 brings up a dialog box showing the main types of celestial objects shown by Guide variable stars galaxies etc and providing control over how they are shown and labelled The Legend option page 24 is checked when the legend is turned on The CCD Frame option toggles the display of a camera frame a resizable rectangle you can use to indicate the area of sky covered by a CCD or film camera When you turn it ON the Frame menu will appear which allows you to position resize and tilt the rectangle The Frame menu is discussed on page 23 The Inversion option brings up a dialog box that lets you reset the orientation of the chart You can use it to make charts that are flipped north south east west or both You can also use it to put the zenith at the top of th
128. talog MCG Morphological galaxy catalog Messier catalog Definition and Finding Displaying and Labelling Nearby stars finding Nebulae Definition and Finding Displaying and Labelling Isophotes NGC Definition and Finding 88 Displaying and Labelling Non stars in the GSC Notes user added NSV New Suspected Variables Finding Displaying and Labelling Occultations Open Clusters Finding Displaying and Labelling Opposition point Outlined stars Overlays Panning PGC Principal Galaxy Catalog Photometric band star display PK Perek Kohoutek nebulae Planets Accuracy controls Accuracy specifications Animating Displaying Finding Labelling Planet features Defined Finding Making lists of Position readout PostScript charts PPM Position and Proper Motion Displaying numbers Precession Printing In color Windows only Fonts Landscape vs Portrait Setting margins Projection Quasars display Radio sources display RC3 Third Revised Catalog Quick Info Realistic background mode RealSky Red Mode Right Ascension See Declination Rotated charts SA1 0 SA2 0 SAO Catalog Definition amp Finding Displaying numbers Satellites artificial 89 20 19 71 Finding Displaying Labelling Setting TLE file Listing passes Screen fonts Settings menu Sharpless nebulae Side Labels Sky Atlas 2000 page number display Sky Commander User library Solar eclipses Display shortcut Tables Star
129. tar Display menu Amore complete description of how the GSC was made can be found in the information distributed with the GSC and copied onto the Guide CD inthe TABLES directory For purposes of aiming you need accurate positions and the GSC positions are indeed usually accurate to a better than one arcsecond However you don t really need accurate magnitudes for aiming Each plate was calibrated using stars near the center of the plate the fact that stars at the edge get distorted wasn t taken into account and stars at the edges of plates get inaccurate magnitudes usually about 5 magnitude errors Also some plates provide magnitudes corresponding to what ahuman eye would see Visual magnitudes while others were sensitive mostly to red light making red stars seem brighter than they would look to a human For finder charts this is usually just enough of a problem to be slightly annoying All the stars in a given region will be offset in brightness by roughly the same amount and you will be able to use the chart to find your way around the sky However if you want to estimate the magnitude of an object by comparing it to a GSC star the errors may become evident Another problem with the GSC has to do with completeness While it has millions of magnitude 14 and 15 stars it omits a few of the brighter stars Again for purposes of aiming the Hubble Space Telescope this did not upset the creators of the GSC very much But it c
130. ter what order you use The next item gives you some control over the field of view shown at a given level Suppose you re at level 9 where the field of view is normally 30 arcminutes The menu item will reflect that fact reading Level 9 30 Suppose you would prefer a slightly smaller field of view say about 24 arcminutes If you click on this menu item Guide will show you a dialog box with the field sizes for all twenty levels You can adjust them as you wish for example you could reset the entry for level 9 to be 24 or 4 as in 4 degrees or 1440 asin 24 times 60 arcseconds these would all be equivalent The size of level 9 would henceforth be 24 not the default 30 If you just want a simple way to get fields of view other than those provided with Guide it s better to use the Fixed Levels option in the Extras menu described on page 53 The Telescope menu is useful if you have an LX 200 Ultima 2000 or Sky Commander connected via serial port to your computer or if you are using the Mel Bartels stepper motor system This menu is described in the Telescope Control chapter on page 38 The Level option brings up a dialog box with 20 buttons Click on one and Guide will switch to that zoom level You can also get to this option by clicking on the Level shown in the legend area or by hitting the 1 to 9 key to get levels 1 9 0 to get level 10 Allt 1 9 to get to levels 11 19 and there are toolbar and mouse
131. tes a year or so into the past 61 or future the fact that the built in data accounts for perturbations will usually mean that it is more accurate than MPCORB anyway The MPC Minor Planet Center has very kindly provided orbital elements for comets suitable for use in Guide on its Web site If you click on Add MPC Comets Asteroids Guide will offer you an option to download comet data Click on this and Guide will download the MPC file it s about 35 KBytes and should be fast even over dialup and merge in the newly found objects and update some comets already known to it You ll also see options to get asteroid data in this manner but it s strongly recommended that you use only the comet option For asteroids there is a better solution use of the MPCORB database This totally replaces Guide s asteroid data instead of just attempting to update it In the Edit Comet data option you may add new comets and asteroids by entering their orbital elements detailed instructions on page 80 This is useful if you want to enter an imaginary object but if you re trying to find areal object it s highly recommended that you use the MPCORB and Add MPC Comets options described above By default Guide shows a trail length for asteroids of zero days that is to say no trail at all If you set this to for example three days then each asteroid will have a little tail behind it showing its motion over the preced
132. that rectangle This issimilar tothe way you can drag abox in some drawing programs There is unfortunately no equivalent way to zoom out Remember Zoom in one level Zoom out one level 1 349 Zoom to levels 1 9 0 Zoom to level 10 Alt 1 9 Zoom to levels 11 19 Select new level Combining panning and zooming youcan move quickly from any point in the sky to any other To find a particular object however you might have to do some hunting and this brings us to our next chapter 5 FINDING OBJECTS As there are many different kinds of objects in the sky and many different ways in which they are named finding objects is given amenu of its own the Go To menu This menu also allows you to send Guide toa variety ofcelestial coordinates and tofind compass points on the horizon In this menu you will see the following list of ways by which you can find an object Object Name Messier NGC TE Onearer Horizon Menu Satellite Planet Planet Feature Comet Asteroid Star Nebula Open Cluster Globular Cluster Constel lat iON Galaxy Coordinates Go To TDF object Star galaxy nebula and coordinate options are discussed in their own subchapters below The Galaxy option also includes clusters of galaxies The first Object Name option is for some people the only option needed Click on it and Guide will ask you to simply enter an object name such as M 57
133. the North Star This slow motion of the Pole is called precession It s similar to what happens with atop you ve probably noticed that while the top spins rapidly it also has a slower wobbling motion This motion makes aRA and declination alone are slightly ambiguous you also need to know the year for which that position is valid That year is called the epoch Most catalogs are in a standard epoch Standard epochs are separated by 50 years some catalogs are still in the B1950 0 epoch while most have been switched to J2000 0 If you read about the position of an object in a book or magazine make sure you also get its epoch This is especially important for dim objects If you mistakenly looked for an object as dim as Pluto say in a J2000 0 position when it was really given as B1950 0 you would have no hope of finding it The difference is usually around half a degree By default Guide shows you positions and accepts positions in J2000 0 If you wish to change this click on the epoch shown in the legend or hit Alt E You can set the epoch in which grids ticks hatches and or side labels are shown separately there is a menu item in the Spacings menu that lets you do this A brief note You may wonder what the B before 1950 0 and the J before 2000 0 mean The answer is in terms of finding something not much In 1950 epochs were measured from the start 77 of the Besselian year which is 365 2421988 days
134. the Remarks i e when you click for more info Because Color index is in carets Guide will show that text highlighted when you click on it you ll get a glossary definition Some datasets store data as special flags For example in the quasar data column 22 can contain an A O R or just a blank space Each flag has ameaning The following lines in the TDF file translate r 22 0 A Position is of low accuracy r 22 0 O Position was found optically and is good to 1 or better r 22 0 R Position was found by radio and is good to 1 or better As it stands nothing is shown if column 22 is blank but using r 22 0 Position is not of low accuracy 70 or something similar would fix that problem 20d Adding note files for TDF datasets It is also possible to add note files for a TDF dataset There is only one example available forthe Binary Star data BINORBIT DAT the last dataset defined in CD_DATA TDF You ll notice that the format description for BINORBIT contains this line n 2 15 binorbit not In plain language this means Notes for this dataset are found in the file BINORBIT NOT and are indexed using the fifteen characters found starting at byte 2 in lines from BINORBIT DAT This example was chosen because the binary orbit dataset already provided notes for most of the stars indexed by their RA dec values which are given in BINORBIT DAT incolumns 2 16 You will see that the NOT file it
135. to add a circle to the overlay The size of the circle depends on how far you drag the mouse In Add Text mode the mouse behaves normally except that 37 if you right click on the chart Guide will prompt you for the text to be added at that point The floating dialog box also has a color selection box The color you select here is applied to anything you add to the overlay Also you can eliminate an overlay entirely with the Delete Overlay option 10 USER OBJECT MENU In the User Object menu you can keep a list of the objects you re interested in that don t appear in the Go To Object set of menus It is in the Overlays menu hotkey F5 The first time you enter it looks like this Add an object Delete an object Go to an object Save to Sky Comm Output to File All items except add an object and esc to prev menu are grayed out since there are no objects yet to be deleted gone to saved to a Sky Commander or output to a file If you center on an object of interest then click on add an object you ll be prompted to enter a name for the object such as Barnard s Star possible variable etc The object will be added to the list and the grayed out menu items will no longer be grayed out If you select Delete an object or Go to an object the complete list of entered objects will be shown Select one and either that object will be removed from the list after you confirm that action or Guide wil
136. torted constellations near the edge of the chart Stereographic projection results in exaggerated sizes of objects near the edge but their shapes are okay Therefore stereographic projection is used for all sky charts in the center of many astronomy magazines Orthographic projection is best suited for terrestrial maps not celestial charts In terrestrial maps one gets an Earth from space sort of view You may want to use it when displaying eclipse occultation paths on the Earth Gnomonic projection involves horrible distortion at large fields of view However it shows great circle routes as straight lines It is therefore useful for meteor observers draw the paths of meteors on this chart and they will appear as straight lines emerging from 32 a single point the radiant Equidistant projection is true in distances and azimuths from the center of the chart It is mostly used for terrestrial charts short wave radio amateurs like its use The Mercator Peters Miller and simple projections are almost never used for sky charts They are all cylindrical projections in which lines of latitude are projected as parallel horizontal lines and lines of longitude are projected as parallel vertical lines For a sky chart read lines of declination and RA or in alt az coordinates lines of altitude and azimuth The price for this is that the north and south poles for sky charts read near the celestial poles become extremely
137. unt of detail may be much more than you really want to know and some of the terms used will be somewhat baffling The links tothe help system will help you though ifterms such as proper motion are new to you a mouse click on them will bring up a definition When you click for more info on a planet Guide will give you some data as to its position distance from you apparent size and what percentage of its surface is illuminated In the case of the Sun it will also give you times when the three different kinds of twilight civil nautical and astronomical begin and end More info onthe Moon also includes data about phases lunar eclipses and librations The Moon rotates at aconstant rate but its orbital speed is not exactly constant this makes it appear to rock back and forth Also its poles alternately tip toward and away from us slightly The end result is that we see a little more than 50 about 59 of its surface The libration data will tell you what part of the moon is currently tipped toward you and therefore more easily observed than it might usually be More info on Jupiter includes satellite events eclipses transits etc over the next week 6a Measuring angular distances on the screen Angular distances between pairs of points on the screen may be easily measured Click with the RIGHT mouse button on the first point holding the mouse button down drag the mouse over to the second point A line will rubber band
138. ve the best possible appearance 14 THE TIME MENU The Time Menu in the Settings menu opens a dialog box which provides many ways to set the time You can also open this box by clicking on the time shown in the legend When you open this dialog you will see something like the following The exact values depend on what your computer s built in clock said when you started Guide 8 Aug 1985 12 03 31 Su Mo Tu We Th Fr Sa 28 29 gt 30 Glo 1 2 3 45 6 F o8 9 10 11 12 13 14 SS Ae 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 bo ee 3 A Se e 7 Time Zone UTC JD 2446282 21078 Time Format Current Time Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec OK Cancel Right at the top is Guide s idea of what the time is By clicking on a button above a figure you can increment it for example each time you click above the 9 in 1985 you will go forward by a century By clicking on a button below a digit you can decrement it If you only want to change a few figures a small amount and don t want to reach for the keyboard this can be very convenient You can also click on the digits in the date time shown in the Legend without even needing to go to the Time dialog Guide s title bar will change as the mouse goes over the digits telling you what a mouse click on that digit will do If you click on the year hour minute and second fields on the second line you can just enter those values f
139. vers are listed on the Project Pluto Web site You can visit any these sites and get a DSS image in FITS format GIF and other formats won t work Click on the Add DSS Image option and specify the name of the image you have just downloaded It will be shown just as if you extracted the data from the CD only the method of importing the image is different To get DSS images from the Internet you should first center the chart on the area of interest and zoom in or out to cover the desired area You can then select if a DSS 1 or DSS 2 R or POSS Palomar Observatory Sky Survey red or blue plate or any of several others should be used DSS images from the Internet are limited to amaximum dimension of 15 arcminutes ask for a larger dimension nd it will get chopped down to that size 55 Click on DSS from Internet and there will be aslight pause while the downloading function starts up After asecond or so the hourglass cursor will turn back to an arrow and the actual downloading of the image will take place in the background This is a good thing since the images can take a while to download The images are requested and retrieved from an STScI Space Telescope Science Institute server and the large size of the image files combined with the slow response of the server can combine to cause it to take a few minutes to actually fetch the image Because itis processed inthe background you can continue to do other things in Gu
140. wanted objects see the section on user overlays on page 36 The steps for creating an ephemeris for a solar system object are very similar to those for creating a trail As before set the current time to match the start of the ephemeris and right click on the object for which you want anephemeris Click on Make Ephemeris and enter the number of steps and their size Again there s an option to have the starting time rounded off to the nearest step size Click OK and Guide will compute the ephemeris and display it on screen You can save the ephemeris to a file or print it much as you could any other help glossary more info item By default Guide will provide some fairly useful data in the ephemerides but you may want to provide different details For example for an artificial satellite the alt az may be of greater interest than the RA dec or you may want to list the percent of an object that is illuminated In such cases it helps to click on the Options button in the Make Ephemeris dialog This leads to a set of check boxes for every item that can be shown in an ephemeris You can also use it to tell Guide to skip ephemeris lines where the object is below the horizon and or it s daylight 49 You do have to exert some restraint here If you enable all of the items that can appear in an ephemeris the lines will be quite long and won t print out or display very intelligibly You can use Guide to make Windows movie
141. y fixed Instead the animation can keep a moving object centered or can stay fixed at a given point relative to the horizon For a good example of the usefulness of the Moving option zoom in on Jupiter at about level 12 and set the animation rate to about 15 minutes Click on Jupiter with the right mouse button the get info button and click OK in the resulting dialog box much as you normally might Now click on the Moving Target option in the Animation 47 Dialog and start animating The effect of this option will be immediately obvious while animating the moving target you selected Jupiter stays at the center of the screen In Stars mode watching Jupiter s moons in animation can be annoying because the planet wanders off the screen much like a telescope without a telescope drive but the Moving option forces a moving target such as a planet asteroid comet or satellite to stay at the center of the chart To see how the Horizon option works go to a Level 4 20 degree field of view Click on Go To Horizon and select NE move to Northeast horizon Go to the Inversion Dialog and select Zenith Up You will see the horizon as a dark blue line near the bottom of the chart and or as a filled in ground area or with objects such as trees if you have selected those options in the Background dialog Go back to the Animation Dialog set a 5 minute stepsize click on the Horizon radio button and start a
142. y plates and so forth These were originally intended as examples but many Guide users have submitted useful datasets that are now incorporated into the program Hitting Toggle user datasets brings up a list of these datasets plus any you may have added using the instructions on the Project Pluto Web site You can click on those you wish to change You ll get a small dialog box where you can turn the dataset on or off change its color set a magnitude limit and so on 53 The Make PostScript file option is described in detail on page 43 Make BMP File provides another way to create graphics files for use in other Windows applications most Windows paint programs will import BMP data To use it set up your chart in the manner in which you want it to appear in the image and click on this option Guide will show the usual Windows save file dialog box and will create a BMP chart with the same dimensions and colors as the current Guide window Find Conjunction and Show Eclipse are described on page 62 Install to Hard Drive is described on page 59 17a DSS REALSKY IMAGES The DSS Digital Sky Survey is a set of digital imagery of the entire sky created from scans of Palomar Sky Survey photos and similar photos from southern sky surveys It s provided on a set of 100 CD ROMs or more commonly via the Internet There is also a more heavily compressed version RealSky provided on 18 CD ROMs but the image quality
143. ys to find both galaxies and clusters of galaxies The menu appears as PGC Uppsala MCG ESO Uppsala CGCG Markarian Abell Cluster Zwicky Cluster Common Name Hickson Arp 10 Many galaxies are better known by a name than by their catalog numbers For example M 51 is better known asthe Whirlpool Galaxy and NGC 5128 is better known as Centaurus A Clicking on Common Name leads to a menu listing some of these objects For each of the following catalogs you can click on the menu item for that catalog and enter a designation Guide will then recenter on that object The PGC Principal Galaxy Catalog lists extensive data for over 160 000 galaxies and is the fundamental galaxy catalog used by Guide The LEDA data is arecent extension to the PGC More info on galaxies comes mostly from these catalogs PGC and PGC LEDA will be used interchangeably The UGC Uppsala Galaxy Catalog is an older catalog of over 10 000 galaxies The MCG Morphological Catalog of Galaxies another older catalog contains data for over 30 000 galaxies MCG designations consist of three numbers with spaces or dashes between them the first number can be negative A letter may be added on as in MCG _ 04 12 133A You can use either dashes or spaces toseparate the numbers for example 4 12 133a will work as well as 04 12 133A The ESO Uppsala European Southern Observatory catalog extends the Uppsala catalog to the southern sky t

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