Universe Sandbox 2 Alpha-12.exe

What is Universe Sandbox?
At its core, Universe Sandbox is a gravity simulator (that very intentionally happens to be fun and easy to use).
Check out the "what is it?" page for more info.
What is Universe Sandbox ²?
Universe Sandbox ² is a complete rewrite of the original and has been in development since fall 2011.
Purchase the Alpha and read more about it here.

Or check out our Universe Sandbox ² FAQ.

What does it look like?
Check out the video preview, user videos, or view screenshots of the program in action.
What's the difference between the free and premium versions?
The free version of Universe Sandbox lets you explore and discover any of the included simulations for as long as you want. The premium version lets you create your own simulations, add new bodies (like planets and stars), and change all the various simulation properties.