Opposite of "satellite"

Question

A satellite is an object which orbits another, what it the word for a object which is being orbited?

The moon is a satellite of Earth, the Earth is a __ of the moon?

Answer 1

The thing that an orbiting body orbits is called that orbiting body’s primary.

Quoth Wikipedia:

A natural satellite, or moon, is a celestial body that orbits another body, e.g. a planet, which is called its primary.