Nested systems

The Moon orbits the Earth while the Earth orbits the Sun. The Moon's orbit is defined inside the Earth's satellite, so it scales and travels with it.

Speed 1×

How it's built

A .satellite is a universe: the .gravity-spot inside it reaches the satellite's edge.
So the Moon on orbit-10 of the Earth's system stays close to the Earth, whatever the size of the page.
Each orbit spins with a CSS animation of rotate on its ring.