A star and all the planets and other bodiess that revolve around it.

A large, round body that revolves around a star in a clear orbit.

The path of one object in space around another object.

Everything that exists, including galaxies and everything in them.

A huge ball of very hot, glowing gas in space that produces its own light and heat.

A group containing billions of stars, objects that revolve around those stars, gas, and dust.

The imaginary line around which Earth rotates.

A chunk of frozen gases, rock, and dust that revolves around the sun.

A nearly round body, slightly smaller than a planet, whose orbit crosses the orbit of another body.

A chunk of rock or iron less than 1,000 km in diameter that revolves around the sun.

The study of objects in space and their properties.