Why the downvotes to that post, people? Most who use stellarium have played with celestia, and vice versa, I've also personally always associated the both of them together.

Celestia was THE play tool I used to play with my new screens/graphic cards for a very, very long time -- not a silly game.

Celestia is great. I get more 'practical' use out of Stellarium, but Celestia is a ton of fun.