SL-16 R/B

SL-16 R/B is a spent rocket body associated with Russia (CIS), launched on 1996-09-04 from Baikonur, Kazakhstan on the Tselina-2 launch. With over 30 years in orbit, it has far exceeded many satellites’ design lifetimes. It orbits in Low Earth Orbit (LEO) at altitudes between 839 km and 863 km with an inclination of 70.8°. It travels at approximately 26,745 km/h (7.43 km/s), completing one full orbit every 102 minutes — that’s roughly 14.12 orbits per day. At its current altitude, the estimated orbital lifetime before atmospheric re-entry is ~100–500 years. Spent rocket bodies like SL-16 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-16 R/B orbits at an average altitude of 851 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-16 R/B’s average altitude, there are currently 234 active payloads and 2,060 tracked debris or rocket body fragments — notable neighbours include NOAA 20, ONEWEB-0179, ONEWEB-0455. With an inclination of 70.8°, SL-16 R/B passes over latitudes between 70.8°N and 70.8°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 1,286 active satellites in total, of which 48 share a similar altitude band with SL-16 R/B.