SL-12 R/B(AUX MOTOR)

SL-12 R/B(AUX MOTOR) is a spent rocket body associated with Russia (CIS), launched on 1985-05-30 from Baikonur, Kazakhstan on the Tselina-2 launch. With over 41 years in orbit, it has far exceeded many satellites’ design lifetimes. It orbits in Low Earth Orbit (LEO) at altitudes between 785 km and 830 km with an inclination of 66.6°. It travels at approximately 26,826 km/h (7.45 km/s), completing one full orbit every 101 minutes — that’s roughly 14.25 orbits per day. At its current altitude, the estimated orbital lifetime before atmospheric re-entry is ~100–500 years. Spent rocket bodies like SL-12 R/B(AUX MOTOR) are among the largest pieces of uncontrolled space debris and are priority targets for collision avoidance manoeuvres and future active debris removal efforts.

SL-12 R/B(AUX MOTOR) orbits at an average altitude of 808 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-12 R/B(AUX MOTOR)’s average altitude, there are currently 438 active payloads and 2,334 tracked debris or rocket body fragments — notable neighbours include NOAA 20, ONEWEB-0179, ONEWEB-0455. With an inclination of 66.6°, SL-12 R/B(AUX MOTOR) passes over latitudes between 66.6°N and 66.6°S, covering most populated land masses in both hemispheres. This mid-inclination band balances global coverage with efficient launch energy requirements. Russia (CIS) operates approximately 1,287 active satellites in total, of which 86 share a similar altitude band with SL-12 R/B(AUX MOTOR).