AMC-21

AMC-21 is an active satellite operated by SES S.A. (SES), launched on 2008-08-14 from Guiana Space Centre, Kourou. After 18 years in orbit, it continues to be tracked by global surveillance networks. It orbits in Geostationary Orbit (GEO) at altitudes between 36,089 km and 36,196 km with an inclination of 3.0°. It travels at approximately 11,023 km/h (3.06 km/s), completing one full orbit every 24.2 hours — that’s roughly 0.99 orbits per day. At geostationary altitude, there is no meaningful atmospheric drag — this object will remain in orbit indefinitely unless actively deorbited. Orbital Radar tracks AMC-21 in real time using the latest two-line element set (TLE) data, providing live position, altitude, speed and orbital path updated continuously.

AMC-21 occupies geostationary orbit at approximately 35,786 km above the equator, where its orbital period matches the Earth’s 24-hour rotation. From the ground, it appears to hover over a fixed point — ideal for broadcast television, weather monitoring and wideband communications. With an inclination of 3.0°, it traces a small figure-of-eight pattern relative to the equator rather than remaining perfectly stationary, which can indicate aging stationkeeping fuel or a deliberate inclined-orbit strategy. Within ±50 km of AMC-21’s average altitude, there are currently 177 active payloads and 8 tracked debris or rocket body fragments. SES operates approximately 77 active satellites in total, of which 23 share a similar altitude band with AMC-21.