slackbuilds/academic/celestia/README

A real-time space simulation that lets you experience our universe in
three dimensions.

There are four frontend possibilities to choose. The Glut one works
out of the box, the GTK one needs gtkglext, and the Gnome one is
untested.  The KDE frontend hasn't been updated since kde3 times, so
it's practically non-functional.

Since the GTK frontend is the default, gtkglext is a required
dependency. Further, lua53 is listed as required dependency, but lua
or lua52 will work as well.