Unformatted text preview: disintegrated, along with a large part of the Earths mantle. A ring of debris formed around the Earth, which at the time would have been covered with a sea of molten rock and quickly accreted to form the Moon. Its overall composition resembles the Earths mantle. The moon probably formed from the debris of a collision. Earth was fairly homogeneous at first, but when iron sank to the center, it differentiated into a metallic core surrounded by a rocky mantle. Why is the Earth Round? When a protoplanet gets big enough, gravity can change its shape. Once a planetesimal becomes big enough, the insides of the planet become warm and the rock becomes soft enough to flow in response to gravity. Also the gravitational force become stronger....
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- Summer '07
- Solar System, Planet, lighter rocky materials, dense iron alloy