EXPLORER 36 (GEOS 2)

EXPLORER 36 (GEOS 2) is an active satellite operated by GSFC (United States), launched on 1968-01-11 from Vandenberg Space Force Base, United States on the Geos B launch. After more than 58 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 1,081 km and 1,573 km with an inclination of 105.8°. It travels at approximately 25,905 km/h (7.20 km/s), completing one full orbit every 112 minutes — that’s roughly 12.84 orbits per day. At its current altitude, the estimated orbital lifetime before atmospheric re-entry is thousands of years. Orbital Radar tracks EXPLORER 36 (GEOS 2) in real time using the latest two-line element set (TLE) data, providing live position, altitude, speed and orbital path updated continuously.

EXPLORER 36 (GEOS 2) orbits at an average altitude of 1,327 km in the uppermost reaches of Low Earth Orbit. At this altitude, orbital decay is effectively zero without active deorbiting, and coverage footprints are significantly larger than lower LEO, though at the cost of higher latency. Within ±50 km of EXPLORER 36 (GEOS 2)’s average altitude, there are currently 20 active payloads and 286 tracked debris or rocket body fragments. This is a relatively sparse altitude band, containing less than 1% of all active satellites. With an inclination of 105.8°, EXPLORER 36 (GEOS 2) passes over latitudes between 105.8°N and 105.8°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 8 share a similar altitude band with EXPLORER 36 (GEOS 2).