A satellite is a moon, planet or machine that orbits a planet or star. For example, Earth is a satellite because it orbits the sun. Likewise, the moon is a satellite because it orbits Earth. Usually, the word "satellite" refers to a machine that is launched into space and moves around Earth or another body in space.
A natural satellite is a celestial body that orbits another celestial body of greater mass (e.g., a planet, star, or dwarf planet), which is called its primary.For example, theMoon is a natural satellite of Earth, and Earth is a natural satellite of the Sun.