noun
- a small rocky or icy body that formed in the early solar system and served as a building block for planets
Usage: astronomy
Examples
- Planetesimals collided and merged to form the planets we see today.
- Scientists study meteorites to learn about the composition of ancient planetesimals.
- The asteroid belt contains remnants of planetesimals that never formed into a planet.
- Computer models show how planetesimals gradually accumulated into larger bodies.
- Some planetesimals were incorporated into comets in the outer solar system.
- The formation of planetesimals marked an important stage in planetary development.