Physics · Planets · Stars
Barycenter
Say it: BAIR-ih-sen-ter IPA: /ˈbærɪˌsɛntər/ noun
Barycenter: The center of mass of a system of bodies.
Two orbiting bodies both move around a shared balance point. That point lies closer to the more massive body and can be inside it or outside it.
- Example
- The two stars circled their common barycenter.
- Why astronomers use it
- It gives a physically useful reference point for describing orbital motion.
- Tiny cosmic connection
- A star can move in response to an orbiting planet; the planet is not the only body doing the orbiting.
Observatory Physics Planets Stars
Where to check it
- NASA: Basics of Space Flight glossary (opens in a new tab)
- Wikipedia: Barycenter (astronomy) (opens in a new tab)
Written for Cool Moon Facts in its own words; the sources cover the same idea in more depth.