Thanks goes to Bill, over at Dubious Quality, for pointing out Stellarium. It is a free, open source planetarium. Here’s a description from the site:
It shows a realistic sky in 3D, just like what you see with the naked eye, binoculars or a telescope.
It is being used in planetarium projectors. Just set your coordinates and go.
Screen shots and additional information are available at the site. The software is currently at release 0.8.0, so expect some bugs, but as with most open source projects past 0.1.0, there are likely not many or very minor.
[tags]Open Source planetarium, Stellarium[/tags]