Planets orbiting the massive star on the left move faster in their orbits than those
orbiting at the same distance from the less massive star on the right.
- Blue planets' distances are equal.
- Left star mass = 2 × right star mass.
- Red planet's speed and right blue planet's speed are equal. Red
planet's distance = 2 × blue planet's distance.
- Red planet's orbital period is MORE than 2 × (inner left blue planet's
Kepler's 3rd law: P ~ r3/2 (not P ~ r !)