KStars is a Desktop Planetarium for KDE. It provides an accurate graphical simulation of the night sky, from any location on Earth, at anydate and time. The display includes 40,000 stars, 13,000 deep-sky objects,all 8 planets, the Sun and Moon, and thousands of comets and asteroids.
kstars - Debian package
http://edu.kde.org/kstars/ - Homepage