Written by the Fiveable Content Team โข Last updated September 2025
Written by the Fiveable Content Team โข Last updated September 2025
Definition
A protoplanet is a large planetary embryo that originated within a protoplanetary disk. It is in the process of developing into a fully-fledged planet through accretion and collisions with other celestial bodies.
5 Must Know Facts For Your Next Test
Protoplanets form from the dust and gas in a protoplanetary disk around a young star.
They grow by the process of accretion, gathering material through gravitational attraction.
Collisions between protoplanets can lead to the formation of larger planets or cause fragmentation.
Our solar system's terrestrial planets likely formed from the collision and combination of several protoplanets.
The Moon may have formed from the debris of a giant impact between Earth and a Mars-sized protoplanet.