3THE TYCHONIAN SYSTEM. The orbits are not to scale, of course, but the rotational periods are proportionally accurate. The Earth completes one “year” in 20 seconds, while Mercury revolves in 4.8 seconds and Saturn in 590 seconds.

The “Tychonian System”: Geocentric. The Sun orbits the Earth, and all the other planets revolve around the Sun.

This demo uses the rotation.css stylesheet to position the “fixed stars” around the solar system; no other elements require it.

1. Ptolemaic System • 2. “Egyptian” System • 3. Tychonian System • 4. Copernican System