XEphem(1X) XEphem(1X)
Name
XEphem - an interactive astronomical ephemeris for X
Syntax
xephem [-prfb] [-install {yes|no|guess}]
Description
XEphem is an interactive astronomical ephemeris program for X Windows
systems with Motif. It provides many graphical views as well as
quantitative heliocentric, geocentric and topocentric information for
Earth satellites, solar system and celestial objects.
XEphem contains extensive context-sensitive on-line help. Virtually
none of that help is duplicated here so go ahead and run XEphem to
learn more.
The Main window of XEphem provides control and display of three basic
services: observing circumstances, looping, and access to additional
tools and displays. Observing circumstances includes location, date,
time and atmospheric conditions (used for the refraction model).
Looping refers to the ability to set up XEphem so that it
automatically increments time at a desired step size and rate.
Additional displays provide all of the graphical and quantitative
information available, and always refer to the circumstances defined
in the main menu. Tools provide access to plotting, searching, AAVSO,
Seti@Home and more.
Options
-prfb displays all the built-in default resources, then exits.
-install controls whether XEphem will install a private colormap.
Without this option XEphem will try to decide automatically whether it
is necessary. To force using a private colormap, use -install yes; to
prevent it use -install no. The default automatic behavior is
equivalent to -install guess.
Menu Tour
File
This menu controls basic operation, including exiting. When XEphem is
first started it may beep. This means a message has been put in the
messages dialog, which can be displayed from this menu. Other chores
here include setting up network access; a simple progress meter;
controlling time and location information remotely.
View
This menu offers several graphical displays if the Earth, Moon and
several planets; a user configurable table displaying; and Sky and
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Solar System views.
Tools
This menu gives access to tools which can plot any XEphem data items;
save any data items to text files for easy export to other programs;
enter an arbitrary function to evaluate and solve using any XEphem
data items; access AAVSO online; monitor your Seti@Home client; show
the Night at a glance; and find close pairs of objects.
Data
This menu gives control over which objects XEphem will work with.
Objects may be created on the fly, read from catalog files, deleted or
searched. A special category of objects known as Field Stars may be
configured, which are very large catalogs of objects whose access has
been optimized. Up to three User objects may be assigned for
especially easy access in several other places throughout XEphem. Also
here is a tool which can update Earth satellite orbital elements from
the web.
Preferences
This menu offers several configuration choices. These will effect the
overall appearance or behavior of XEphem. These choices, as well as
fonts and colors, can be changed at runtime and saved to disk to
become the new defaults.
Help
This menu offers overall information about B .XEphem; context
sensitive help; several worked examples; references; version number
and the Copyright statement.
X Resources
XEphem initial conditions are defined using a resource file. By
default the file is named XEphem located in a directory also called
XEphem in your $HOME directory. You will want to tune some of these to
your taste and circumstances; most may be left unchanged.
Time zones
XEphem will attempt to obtain time zone information from the host
operating system. If this fails for some reason, time zone offset and
name may also be set manually at any time from the Main menu.
Author
Elwood Downey, email ecdowney@ClearSkyInstitute.com.
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XEphem(1X) XEphem(1X)
References
The latest information about XEphem is maintained at
http://www.clearskyinstitute.com/xephem
The online Help entry on Credits lists many of the references,
individuals and organizations which have contributed to XEphem.
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