A geosynchronous orbit (sometimes abbreviated GSO) is an Earth-centered orbit with an orbital period that matches Earth's rotation on its axis, 23 hours, 56 minutes, and 4 seconds (one sidereal day).

Artistic impression of European Data Relay Satellite (EDRS) system (not to scale). These satellites work in GEO and relay data to and from non-GEO satellites, spacecraft, and stations that aren’t ...

First, Russia has now joined the fray with the recent arrival of its own suspected inspector (or attack) satellite in GEO.

DARPA is preparing to test one of the most ambitious orbital servicing missions ever attempted: a robotic spacecraft capable ...