turn on or around an axis or a center
move in an orbit
a push or pull exerted on an object
a force of attraction between objects that is due to their masses
the path of an object as it revolves around another object in space
an imaginary line that passes through Earth's center and its North and South Poles
the distance light travels in one year
any natural or artificial object that revolves around another object
a mixture of gases that surrounds a planet or moon
the tendency of a body to maintain is state of rest or uniform motion unless acted upon by an external force
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