SL-12 R/B(AUX MOTOR)

SL-12 R/B(AUX MOTOR) is a spent rocket body associated with Russia (CIS), launched on 1970-12-02 from Baikonur Cosmodrome, Kazakhstan on the L-1e No. 2K launch. After more than 56 years in orbit, it is one of the longest-surviving objects in the space catalogue. It orbits in Medium Earth Orbit (MEO) at altitudes between 1,585 km and 5,087 km with an inclination of 51.6°. It travels at approximately 23,069 km/h (6.41 km/s), completing one full orbit every 2 hours 39 minutes — that’s roughly 9.07 orbits per day. Its orbital eccentricity of 0.1804 gives it a noticeably elliptical path, with significant altitude variation between perigee and apogee. 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 3,336 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-12 R/B(AUX MOTOR)’s average altitude, there are currently 3 active payloads and 4 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 51.6°, SL-12 R/B(AUX MOTOR) passes over latitudes between 51.6°N and 51.6°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 1,537 active satellites in total.