For more info and a download, follow this link: http://en.spaceengine.org/
It's only 400MB in size.
Oh, and you can actually land on every single one of the trillions of planets. To show you how much detail there is, here are a couple of screenshots:
These screenshots aren't mine. My computer can't handle the amount of detail, but I hope some of you with beefier computers will post some screenshots of your own.
Spread the word around. This project is amazing.
Edited by gtathebest4ever, 30 August 2011 - 12:13 PM.