Micrometeorite (noun)

A small particle of rock or metal that is believed to have originated from outer space and that has fallen to the earth's surface.

Origin:

Mid 20th century: from micro- + meteorite.

Examples:

1. Micrometeorites are extremely small and often go unnoticed.
2. The study of micrometeorites helps scientists understand the composition of the early solar system.
3. Micrometeorites can provide important information about the conditions that existed in the early solar system.
4. Scientists use special tools and techniques to identify and study micrometeorites.
5. The collection of micrometeorites is an important part of the study of planetary science.