Kepler's Orrery

Keplers Orrery is a generative music system that uses gravity equations to compose and play ambient music.

Start with a world: there are planets and rocks. They attract each other with the basic gravitational equations. When they collide, they make music.

The music differs with each world. Sometimes slow and ambient; sometimes random, sharp, and surprising.

You can play with the physics: change the gravitational constant; add "antigravity" or friction; visualize the force fields and velocities.
With the world editor, you can change the mass, initial positions and velocities of the bodies and then restart the world to see how it comes out different. Turn on tilt gravity to let the real world influence the simulated world.