SECOR 13 (EGRS 13)

SECOR 13 (EGRS 13) is an active satellite operated by USA ETL (United States), launched on 1969-04-14 from Vandenberg Space Force Base, United States on the Nimbus B2 launch. After more than 57 years in orbit, it is one of the longest-surviving objects in the space catalogue. It orbits in Low Earth Orbit (LEO) at altitudes between 1,069 km and 1,127 km with an inclination of 99.6°. It travels at approximately 26,299 km/h (7.31 km/s), completing one full orbit every 107 minutes — that’s roughly 13.43 orbits per day. At its current altitude, the estimated orbital lifetime before atmospheric re-entry is ~500–1,000 years. Orbital Radar tracks SECOR 13 (EGRS 13) in real time using the latest two-line element set (TLE) data, providing live position, altitude, speed and orbital path updated continuously.

SECOR 13 (EGRS 13) orbits at an average altitude of 1,098 km in the upper LEO band, where atmospheric drag is negligible and objects can persist for centuries to millennia. This altitude is used by broadband constellations like OneWeb and by scientific missions requiring stable orbits far from the densest debris bands. Within ±50 km of SECOR 13 (EGRS 13)’s average altitude, there are currently 301 active payloads and 511 tracked debris or rocket body fragments — notable neighbours include ONEWEB-0041. With an inclination of 99.6°, SECOR 13 (EGRS 13) passes over latitudes between 99.6°N and 99.6°S, providing near-global coverage including the polar regions. Polar and near-polar orbits are used for reconnaissance, weather monitoring and Earth-observation missions that need to image every part of the planet. United States operates approximately 13,279 active satellites in total, of which 39 share a similar altitude band with SECOR 13 (EGRS 13).