Unix Based Astronomy App Runs On OS X

XEphem 3.4, a Unix based full-featured Astronomy program, has been compiled to run via an X-Windows implementation under Mac OS X. X-Windows basically functions as a graphical shell for the variants of the Unix operating system, and there are currently two implementations of X-Windows for Mac OS X. XEphem functionality requires that you use one of these two X-Windows builds. According to the XEphem Web site:

XEphem, the brainchild of programmer Elwood Downey, is a star-charting, sky-simulating, ephemeris-generating celestial virtuoso that can do just about everything that the usual Windows and Macintosh star-charting software can do -- and sometimes quite a bit more. And itis completely free. Whatis not to like?

Bob Brose walks users through many of the details of compiling XEphem for use under Mac OS X on his Web site. According to Mr. Brose:

Xephem for Mac OSX. Requires XFree86 4.02 (or newer) for Darwin (more info on this is at the Darwinfo site). To run this you need to exit the MacOS GUI and login on the text console where you can startup X. The Darwin developers are working on an open source implementation of XWindows which runs along side of Aqua and itis now working pretty well! See XonX for more info. For a commercial alternative see the Tenon X-TOOLS which uses Aqua as a display device for an X server. This allows X based apps to run inside of Aqua.

You can find more information on XEphem at the Clear Sky Institute Web site, and more details on compiling and installing XEphem for Mac OS X at Mr. Broseis Web site.