How was Uranus formed?

[Craig]

Interested article: http://www.space.com...nus-formed.html

There are two theories as to how planets in the solar system were created. The first and most widely accepted, core accretion, works well with the formation of the terrestrial planets but has problems with giant planets such as Uranus. The second, the disk instability method, may account for the creation of giant planets.

[Daz Type-R]

That's not where I thought this thread was going.......

[Guest Tweedledum]

The accretion model follows well for the inner 'rocky' planets, with the late heavy bombardment and the collision with another similar sized body to the earth that eventually fragmented to earth and moon.

But the gas giants pose some interesting issues. In that Jupiter is almost big enough to become a star, and emits more energy than it receives from the sun, so both Uranus and Neptune are postulated to have been formed early from instabilities in the original dust clouds and have a similar composition to that of comets. It could have been possible that a nearby star blew off the remnant of the extremities of the original cloud leaving the outer gas giants. This is 'Boss's' model.

Phew..

Cheers

Damian