Secondary body

In astrodynamics, an orbiting body (${\displaystyle m_{2}}$) is a body that orbits a primary body (${\displaystyle m_{1}}$).

The orbiting body is properly referred to as the secondary body.

It is less massive than the primary body (i.e. ${\displaystyle m_{1}>m_{2}}$).

Under standard assumptions in astrodynamics the barycenter of the two bodies is a focus of both orbits.

Pertaining to astronomy, an orbiting body (sometimes seen as OB) is any object smaller than the body it orbits. These may include, but are not limited to, comets, planets, dwarf planets, moons, and asteroids.

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