XEphem (v3.2.3) is an interactive astronomy program for Motif Window systems. 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 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. Latest info is at http://www.ClearSkyInstitute.com/xephem/xephem.html.