Stellarium

Stellarium http://www.stellarium.org/ is a FREE planetarium program, quick to download, quick to install, works on any computer. Enables you (and your students) to look at the night sky, pick out planets, stars, nebulas, galaxies. Go backward and forward in time, speed time up, slow it down, watch the phases of the moon, or watch Europa orbit Jupiter. Find the larger asteroids in the asteroid belt, or even look at Hubble's photos of distant heavenly bodies.