The listing, Universe Sandbox - Steam Key has ended.
Universe Sandbox - Steam Key
Release Date: 29 Apr 2011
http://store.steampowered.com/app/72200/
About the Game
Create and destroy on a scale you've never imagined with the ultimate space simulator.
Harness the power to create black holes, collide galaxies, and manipulate gravity with just a few clicks. Inspired by the software astronomers use to unlock the mysteries of our universe, never before has astronomy been so interactive or so much fun.
Spawn a massive moon to tear apart Saturn’s rings or launch a rogue star to rip the planets from their orbits around our sun. After unleashing catastrophic destruction, create your own solar system and share it with friends.