"XEphem, the brainchild of programmer Elwood Downey, is a star-charting, sky-simulating, ephemeris-generating celestial virtuoso that can do just about everything ... what's not to like?"
The scientific-grade interactive astronomical ephemeris software package for UNIX-like systems. Written in C, X11 and Motif with full source code freely available, easily ported to systems including:
• Linux • FreeBSD • MacOS X (screen shot) and (review) • Solaris • AIX • HP-UX • OpenVMS • Windows using Cygwin