SL-8 R/B

SL-8 R/B is a spent rocket body associated with Russia (CIS), launched on 1990-02-27 from PKMTR on the Nadezhda 17F118 No. 405 launch. With over 36 years in orbit, it has far exceeded many satellites’ design lifetimes. It orbits in Low Earth Orbit (LEO) at altitudes between 948 km and 1,009 km with an inclination of 83.0°. It travels at approximately 26,512 km/h (7.36 km/s), completing one full orbit every 105 minutes — that’s roughly 13.76 orbits per day. At its current altitude, the estimated orbital lifetime before atmospheric re-entry is ~100–500 years. Spent rocket bodies like SL-8 R/B are among the largest pieces of uncontrolled space debris and are priority targets for collision avoidance manoeuvres and future active debris removal efforts.

SL-8 R/B orbits at an average altitude of 979 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 SL-8 R/B’s average altitude, there are currently 304 active payloads and 973 tracked debris or rocket body fragments. With an inclination of 83.0°, SL-8 R/B passes over latitudes between 83.0°N and 83.0°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. Russia (CIS) operates approximately 1,287 active satellites in total, of which 160 share a similar altitude band with SL-8 R/B.