Michael, Ipswich asked:
Why have planets got most of the solar system's angular momentum?
Dominic - I think thatís actually one of the real puzzles of our solar system, why the mass is all in the Sun, but the angular momentum is all in the planets that orbit around it. JohnÖ
John - Yes, I mean something must have happened to bring that about because as you said earlier, the Sun and the planets formed out of one rotating disk of materials. So something has happened to give us this situation where the angular momentum is in the planets rather than the Sun. So, theorists come up with all sorts of great theories involving viscosity and friction and so on to explain it away, but itís a perceptive question.