1XEphem(1X)
2XEphem(1X)
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6[1mName[0m
7       XEphem ‐ an interactive astronomical ephemeris for X11
8
9[1mSyntax[0m
10       [1mxephem  [‐prfb]  [‐install  {yes|no|guess}]   [‐resfile
11<resourcefile>][0m
12       [1m[‐[no]splash][0m
13
14[1mDescription[0m
15       XEphem  is  an  interactive astronomical ephemeris program
16for the X
17       Window System.  It provides many graphical views  as  well
18as
19       quantitative  heliocentric, geocentric and topocentric in‐
20formation for
21       Earth satellites, solar system and celestial objects.
22
23       XEphem primarily uses two directories at runtime.  One  is
24referred to as
25       the  Shared directory, the other as the Private directory.
26Shared is
27       read‐only and holds supporting files that  can  be  shared
28among all users
29       on  a  system.  Private is writable and one is expected to
30exist for each
31       user. See the section below on X Resources for more infor‐
32mation about
33       defining these directories.
34
35       XEphem  contains extensive context‐sensitive on‐line help.
36Virtually
37       none of that help is duplicated here so go ahead  and  run
38XEphem to
39       learn  more.  The  first  thing to do once XEphem is up is
40configure the
41       browser interface. All of XEphem help is written  in  html
42and stored in
43       a file named xephem.html. The first entry in the Help menu
44brings up a
45       table of browsers and defines a command for each that will
46invoke the
47       browser and pass it the URL and anchor of the text to dis‐
48play. XEphem
49       comes configured to support several different browsers. If
50yours is
51       listed,  just  click  the button to its left and your help
52system should
53       be working. If your browser is not  listed,  please  check
54the FAQ for the
55       latest news.
56
57       Note  that  if you are running XEphem under cygwin on Win‐
58dows, before
59       starting XEphem set an environment variable  XEHELPURL  to
60the full path
61       of  the xephem.html file on your system using Windows path
62syntax (not
63       cygwin paths).  This file is in the [4mhelp[24m  directory
64within the source
65       directory  of  the  master distribution.  After this is in
66the place, run
67       xephem and it can use MS IE to display help.
68
69       The XEphem [4mMain[24m [4mwindow[24m is the  master  panel
70for setting up observing
71       circumstances, time looping, and for accessing all the ad‐
72ditional tools
73       and displays.  Observing circumstances includes  location,
74date, time,
75       local  magnetic deviation and atmospheric conditions (used
76for the
77       refraction model).  Looping provides the ability to set up
78XEphem so
79       that  it  automatically  increments time at a desired step
80size and rate.
81       Additional displays provide all of the graphical and quan‐
82titative
83       information  available, which are always computed with re‐
84spect to the
85       circumstances defined in the Main menu. Tools provide  ac‐
86cess to
87       plotting, searching, AAVSO and much more.
88
89
90[1mCommand line Options[0m
91       [1m‐prfb  [22mdisplays all the built‐in default resources,
92then exits. Some of
93       them are described here.
94
95       [1m‐install [22mcontrols whether  XEphem  will  install  a
96private colormap.
97       Without this option XEphem will try to decide automatical‐
98ly whether it
99       is necessary. To force using a private colormap, use  [4m‐
100install[24m [4myes.[24m  To
101       prevent  it,  use  [4m‐install[24m [4mno.[24m  The default
102automatic behavior is
103       equivalent to [4m‐install[24m [4mguess.[0m
104
105       [1m‐resfile <resourcefile> [22mtells XEphem to use an  al‐
106ternate file for
107       initial resource settings. See below for the default situ‐
108ation.
109
110       [1m‐splash [22mor [1m‐nosplash [22mcontrols whether XEphem
111will display a progress
112       window  front and center while it is coming up. The choice
113is yours
114       because this can be a useful sign of life on a  slow  sys‐
115tem, or be the
116       source  of an annoying flash on a fast system. The setting
117is persistent
118       so it will remain until changed.
119
120
121[1mMenu Tour[0m
122       [1mFile[0m
123
124       This menu controls access to the System  log;  setting  up
125network access;
126       accessing  the  gallery; displaying a progress meter; con‐
127trolling time
128       and location information remotely; and keyboard  accelera‐
129tors for time
130       stepping.
131
132       [1mView[0m
133
134       This  menu  offers  several graphical displays if the Sun,
135Earth, Moon and
136       several planets; a user configurable data table;  and  Sky
137and Solar
138       System views.
139
140       [1mTools[0m
141
142       This  menu gives access to tools which can plot any XEphem
143data items;
144       save any data items to text files for easy export to other
145programs;
146       enter  an  arbitrary  function to evaluate and solve using
147any XEphem data
148       items; access AAVSO online; show the Night  at  a  glance;
149find close
150       pairs  of objects; convert among various astonomical coor‐
151dinate systems;
152       and a handy log for taking observing notes.
153
154       [1mData[0m
155
156       This menu gives control over  which  objects  XEphem  will
157work with.
158       Objects  may  be  created  on  the  fly, read from catalog
159files, downloaded
160       from the Internet, deleted or searched. A special category
161of objects
162       known  as  [4mField[24m  [4mStars[24m  may  be configured,
163which are very large catalogs
164       of objects whose access has been optimized. Any number  of
165[4mFavorite[0m
166       objects  may be defined for especially easy access in sev‐
167eral other
168       places throughout XEphem.
169
170       [1mPreferences[0m
171
172       This menu offers several configuration choices  and  tools
173for changing
174       fonts  and  colors  used throughout XEphem.  These choices
175can be changed
176       at runtime and saved to disk to become the new defaults.
177
178       [1mHelp[0m
179
180       This menu offers overall information about XEphem; context
181sensitive
182       help;  references; version number and the Copyright state‐
183ment.
184
185
186[1mX Resources[0m
187       When  first  started,  XEphem  looks  for  a  file   named
188[1m.xephemrc [22min your
189       $HOME directory. It should contain one line of the form:
190
191       XEphem.PrivateDir: ~/.xephem
192
193       This  defines  the  Private  directory,  where XEphem will
194store your
195       personal settings. The example line shown here,  which  is
196also the
197       assumption  if  the file is not present, means XEphem will
198create and use
199       a directory named [1m.xephem [22mfor this purpose in  your
200home directory.
201
202       Within this directory a text file named [1mXEphem [22mwill
203contain all the
204       Preferences that differ from those built in. One important
205entry
206       defines the Shared directory. This is in intended for mul‐
207ti‐user
208       installations. XEphem looks here for support files. Unless
209defined
210       otherwise,  the Shared directory is ".", that is, the cur‐
211rent directory.
212
213
214[1mAuthor[0m
215       Elwood C. Downey, email ecdowney@ClearSkyInstitute.com.
216
217
218[1mReferences[0m
219       The Web homepage, including the FAQ, is maintained at
220       [4mhttp://www.clearskyinstitute.com/xephem[0m
221
222       The online Help entry [4mon[24m [4mCredits[24m lists  many
223of the references,
224       individuals  and  organizations  which have contributed to
225XEphem.
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