1[4mXEphem[24m(1X)
2[4mXEphem[24m(1X)
3[1mName[0m
5 XEphem ‐ an interactive astronomical ephemeris for X11
6[1mSyntax[0m
8 [1mxephem [‐prfb] [‐install {yes|no|guess}] [‐resfile
9<resourcefile>][0m
10 [1m[‐[no]splash][0m
11[1mDescription[0m
13 XEphem is an interactive astronomical ephemeris program
14for the X
15 Window System. It provides many graphical views as well
16as
17 quantitative heliocentric, geocentric and topocentric in‐
18formation for
19 Earth satellites, solar system and celestial objects.
20 XEphem primarily uses two directories at runtime. One is
22referred to as
23 the Shared directory, the other as the Private directory.
24Shared is
25 read‐only and holds supporting files that can be shared
26among all users
27 on a system. Private is writable and one is expected to
28exist for each
29 user. See the section below on X Resources for more infor‐
30mation about
31 defining these directories.
32 XEphem contains extensive context‐sensitive on‐line help.
34Virtually
35 none of that help is duplicated here so go ahead and run
36XEphem to
37 learn more. The first thing to do once XEphem is up is
38configure the
39 browser interface. All of XEphem help is written in html
40and stored in
41 a file named xephem.html. The first entry in the Help menu
42brings up a
43 table of browsers and defines a command for each that will
44invoke the
45 browser and pass it the URL and anchor of the text to dis‐
46play. XEphem
47 comes configured to support several different browsers. If
48yours is
49 listed, just click the button to its left and your help
50system should
51 be working. If your browser is not listed, please check
52the FAQ for the
53 latest news.
54 Note that if you are running XEphem under cygwin on Win‐
56dows, before
57 starting XEphem set an environment variable XEHELPURL to
58the full path
59 of the xephem.html file on your system using Windows path
60syntax (not
61 cygwin paths). This file is in the [4mhelp[24m directory
62within the source
63 directory of the master distribution. After this is in
64the place, run
65 xephem and it can use MS IE to display help.
66 The XEphem [4mMain[24m [4mwindow[24m is the master panel
68for setting up observing
69 circumstances, time looping, and for accessing all the ad‐
70ditional tools
71 and displays. Observing circumstances includes location,
72date, time,
73 local magnetic deviation and atmospheric conditions (used
74for the
75 refraction model). Looping provides the ability to set up
76XEphem so
77 that it automatically increments time at a desired step
78size and rate.
79 Additional displays provide all of the graphical and quan‐
80titative
81 information available, which are always computed with re‐
82spect to the
83 circumstances defined in the Main menu. Tools provide ac‐
84cess to
85 plotting, searching, AAVSO and much more.
86[1mCommand line Options[0m
89 [1m‐prfb [22mdisplays all the built‐in default resources,
90then exits. Some of
91 them are described here.
92 [1m‐install [22mcontrols whether XEphem will install a
94private colormap.
95 Without this option XEphem will try to decide automatical‐
96ly whether it
97 is necessary. To force using a private colormap, use [4m‐
98install[24m [4myes.[24m To
99 prevent it, use [4m‐install[24m [4mno.[24m The default
100automatic behavior is
101 equivalent to [4m‐install[24m [4mguess.[0m
102 [1m‐resfile <resourcefile> [22mtells XEphem to use an al‐
104ternate file for
105 initial resource settings. See below for the default situ‐
106ation.
107 [1m‐splash [22mor [1m‐nosplash [22mcontrols whether XEphem
109will display a progress
110 window front and center while it is coming up. The choice
111is yours
112 because this can be a useful sign of life on a slow sys‐
113tem, or be the
114 source of an annoying flash on a fast system. The setting
115is persistent
116 so it will remain until changed.
117[1mMenu Tour[0m
120 [1mFile[0m
121 This menu controls access to the System log; setting up
123network access;
124 accessing the gallery; displaying a progress meter; con‐
125trolling time
126 and location information remotely; and keyboard accelera‐
127tors for time
128 stepping.
129 [1mView[0m
131 This menu offers several graphical displays if the Sun,
133Earth, Moon and
134 several planets; a user configurable data table; and Sky
135and Solar
136 System views.
137 [1mTools[0m
139 This menu gives access to tools which can plot any XEphem
141data items;
142 save any data items to text files for easy export to other
143programs;
144 enter an arbitrary function to evaluate and solve using
145any XEphem data
146 items; access AAVSO online; show the Night at a glance;
147find close
148 pairs of objects; convert among various astonomical coor‐
149dinate systems;
150 and a handy log for taking observing notes.
151 [1mData[0m
153 This menu gives control over which objects XEphem will
155work with.
156 Objects may be created on the fly, read from catalog
157files, downloaded
158 from the Internet, deleted or searched. A special category
159of objects
160 known as [4mField[24m [4mStars[24m may be configured,
161which are very large catalogs
162 of objects whose access has been optimized. Any number of
163[4mFavorite[0m
164 objects may be defined for especially easy access in sev‐
165eral other
166 places throughout XEphem.
167 [1mPreferences[0m
169 This menu offers several configuration choices and tools
171for changing
172 fonts and colors used throughout XEphem. These choices
173can be changed
174 at runtime and saved to disk to become the new defaults.
175 [1mHelp[0m
177 This menu offers overall information about XEphem; context
179sensitive
180 help; references; version number and the Copyright state‐
181ment.
182[1mX Resources[0m
185 When first started, XEphem looks for a file named
186[1m.xephemrc [22min your
187 $HOME directory. It should contain one line of the form:
188 XEphem.PrivateDir: ~/.xephem
190 This defines the Private directory, where XEphem will
192store your
193 personal settings. The example line shown here, which is
194also the
195 assumption if the file is not present, means XEphem will
196create and use
197 a directory named [1m.xephem [22mfor this purpose in your
198home directory.
199 Within this directory a text file named [1mXEphem [22mwill
201contain all the
202 Preferences that differ from those built in. One important
203entry
204 defines the Shared directory. This is in intended for mul‐
205ti‐user
206 installations. XEphem looks here for support files. Unless
207defined
208 otherwise, the Shared directory is ".", that is, the cur‐
209rent directory.
210[1mAuthor[0m
213 Elwood C. Downey, email ecdowney@ClearSkyInstitute.com.
214[1mReferences[0m
217 The Web homepage, including the FAQ, is maintained at
218 [4mhttp://www.clearskyinstitute.com/xephem[0m
219 The online Help entry [4mon[24m [4mCredits[24m lists many
221of the references,
222 individuals and organizations which have contributed to
223XEphem.
224 [4mX‐
226Ephem[24m(1X)
227