How did planetesimals form planets

when a planetary system is forming, there is a protoplanetary disk with materials from the nebulae from which the system came.

Answer: Planetesimals. A planetesimal is an object formed from dust, rock, and other materials ... The planetesimal theory is a theory on how planets form. According to the planetesimal hypothesis, when a planetary system is forming, there is a protoplanetary disk with materials from the nebulae from which the system came

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