A moon or a man-made body in orbit around a planet.

For clarity, natural satellites are commonly described as "moons" to distinguish them from man-made or artificial satellites.

Relay station in space for sending telephone, television, telex, and other messages around the world.

Messages are sent to and from the satellites via ground stations. Most communications satellites are in geostationary orbit, appearing to hang fixed over one point on the earth's surface.

Concept for providing large amounts of electricity for use on the earth from one or more satellites in geosynchronous earth orbit.

A very large array of solar cells on each satellite would provide electricity, which would be converted to microwave energy and beamed to a receiving antenna on the ground. There, it would be reconverted into electricity and distributed the same as any other centrally generated power, through a grid.