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Name: Christie
Status: student
Grade: 9-12
Location: SC
Country: USA
Date: May 2, 2011

What specific evidence indicates that the planets formed at the same time as the sun?

Dear Christie,

That is a very good question. The ignition of the Sun followed a slow process of condensation of the solar nebula, which was forming the sun at the center and the planets in the outskirts. Our nascent solar system pretty well formed at the same time, according to current theories. The planets were gaseous-- the smaller one condensed from rock while the outer, bigger ones were mostly gaseous. There were many, many impacts as part of this process; one formed our Moon while another put Uranus on its side.

I hope this helps.

David H. Levy


I do not think there is evidence that indicates that the planets and sun formed at the same time.

And what do you mean by "the same time?" At solar system forming level time frames what is the meaning of a day, a week, or a month?

I believe the process was that a turbulent gas cloud made of raw matter started to mutually attract each other due to the gravity of the matter and they accreted ( into smaller bodies and then into larger and larger bodies until the bodies solidified into our present solar system and, given this process, I do not think it could be said that all of the planets and the sun formed at exactly the same time.

Sincere regards, Mike Stewart

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