This gravity simulation is a sandbox on a grand scale. Put planets, stars, and asteroids in place, give them an initial push, and see where they go. Observe the conic sections that emerge from the simple rules of gravitational attraction.

Why stop there? Go ahead and simulate what we might observe if gravity deviates from a 1/r^2 law. Change the law just a little, and try to recreate the strange and famous behavior of Mercury.

Throughout it all there will be beautiful and captivating pictures. So go make some worlds, and make some art.

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For even more features, take a look at the downloadable version here: http://testtubegames.com/gravity_full.html