Naked Science Forum

Non Life Sciences => Physics, Astronomy & Cosmology => Topic started by: chris on 10/04/2009 10:59:56

Title: Why does Jupiter have so many moons yet Earth has just one?
Post by: chris on 10/04/2009 10:59:56

Jupiter has about 30 moons whilst we have just one. Why is this?

Chris

Title: Why does Jupiter have so many moons yet Earth has just one?
Post by: syhprum on 10/04/2009 11:57:54

The inner planets have virtually no moons except Earth that can better be regarded as a twin planet.
only large planets such as Jupiter one thousand times the mass of the earth can hang onto their primeval moons that are the residue of their creation.

Title: Why does Jupiter have so many moons yet Earth has just one?
Post by: Don_1 on 10/04/2009 13:00:28

Earth does not have a gravitational field strong enough to hold another satellite in orbit. Then there is the problem of our proximity to the Sun, Mars and Venus.

A second satellite would have to be of a sufficient distance from Earth not to interfere with the Moon's orbit. This would put it too close to the orbit of both Mars & Venus which might influence that satellite's orbit. Certainly the Sun's gravitational field would have a considerable effect on a satellite orbiting so far from Earth.

Jupiter has the mass to maintain a far stronger and further reaching gravitational field than Earth. It also has far more space in which it's satellites can orbit, since it's neighbouring planets are much further from it than earth's. The greater influence which Jupiter has on it's satellites and the weaker influence of the Sun's gravitational field at that distance allows Jupiter to have many more moons than smaller planets nearer the sun could possibly maintain.