Build an interactive animated Solar System visualization.
Include:
- the Sun
- all eight planets
- planetary orbits
- Earth's Moon
- several major moons of Jupiter
- relative orbital speeds
- orbital trails
- pause/resume
- adjustable simulation speed
- zoom and pan
- clicking a planet to inspect it
- switching between a Solar System view and a selected-planet view
Moons must continue orbiting their parent planet correctly while the planet itself moves around the Sun.
Changing simulation speed must not cause objects to jump or lose orbital state.
