Celestia has a new release out and one of the big changes in this release is that it is now usable from within other applications. So you could build a complete educational program about the solar system and put Celestia right into the program. That’s pretty cool. I also spotted a new astronomy project I had not seen before called Stellarium. It attempts to depect what you might see if you actually go outside. That is, it displays stars but it also shows the horizon line, haze nearer the ground, etc. to make a kind of “realistic” planetarium.