a long but simple question: the mass of jupiter is Mjupiter=300Mearth. Jupiter orbits around the sun with Tjupiter=11.9 years in an orbit rjupiter=5.2rearth (r=radius) suppose the earth could be moved to the distance of jupiter and placed in circular orbit around the sun. what would be the new period (T) of the earth`s orbit?

Question

anonymous · Answer

If the earth was moved out to the same distance as Jupiter, then it's orbital period would increase by the same factor, to 5.2 years.
The answer follows from Kepler's third law, and is independent of the planets' masses, to a good approximation.