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In astronomy, the word satellite refers to any single object that is orbiting another larger, more massive object under the influence of their mutual gravitational force.

A natural satellite is any celestial body orbiting a planet or star of larger size. The Moon is the natural satellite of Earth. The other solar

system planets that have natural satellites (moons) are Mars (2), Jupiter (28), Saturn (18 known, additional 12 reported), Uranus (21), Neptune (8), and Pluto (1).

Artificial satellites are human-made devices that orbit Earth and other celestial bodies. These devices follow the same gravitational laws that govern the orbits of natural satellites. After being launched from Earth, artificial satellites are placed high enough to escape the denser parts of the atmosphere, which would slow down the orbit of the satellite and cause it to plummet to the ground. At the proper height, usually above 200 miles...