SL-14 R/B

SL-14 R/B is a spent rocket body associated with Russia (CIS), launched on 1989-09-28 from PKMTR on the AUOS-Z No. 201 launch. With over 37 years in orbit, it has far exceeded many satellites’ design lifetimes. It orbits in Medium Earth Orbit (MEO) at altitudes between 499 km and 2,425 km with an inclination of 82.6°. It travels at approximately 25,681 km/h (7.13 km/s), completing one full orbit every 115 minutes — that’s roughly 12.51 orbits per day. Its orbital eccentricity of 0.1229 gives it a noticeably elliptical path, with significant altitude variation between perigee and apogee. At its current altitude, the estimated orbital lifetime before atmospheric re-entry is thousands of years. Spent rocket bodies like SL-14 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-14 R/B orbits at an average altitude of 1,462 km in Medium Earth Orbit, the region between LEO and GEO (2,000–35,786 km). MEO’s higher altitude gives each satellite a much larger ground footprint than LEO, meaning fewer spacecraft are needed for global coverage — but signal latency is higher and radiation from the Van Allen belts is a significant design constraint. Within ±50 km of SL-14 R/B’s average altitude, there are currently 376 active payloads and 247 tracked debris or rocket body fragments. With an inclination of 82.6°, SL-14 R/B passes over latitudes between 82.6°N and 82.6°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. Russia (CIS) operates approximately 1,287 active satellites in total, of which 340 share a similar altitude band with SL-14 R/B.