Topic List

Click a topic to learn more.


Term of the Moment

deep Web


Look Up Another Term


Definition: LEO


(Low-Earth Orbit) A communications satellite in orbit roughly 100 to 1,200 miles above the earth. Below 280 miles, LEO satellites are often called VLEO (very-low-earth orbit) satellites.

LEOs revolve around the planet in two hours or less, and a single LEO is in view for only a few minutes. In order to provide coverage to the whole planet, from 48 to 66 LEOs are required. Because they are the closest to the ground of all satellites, signals make the round trip from earth much faster. Thus, low-power "pizza dish" antennas and handheld devices can be used. LEOs are also better suited to interactive conferencing. See Iridium, Teledesic, GEO, MEO and HEO.




It Takes a Lot of LEOs
While the footprint of a GEO can cover the bulk of a continent, it takes many LEOs to cover the same area. Signals also travel to and from LEOs faster, making them more suitable for real-time applications than GEOs.