SL-12 R/B(AUX MOTOR)

SL-12 R/B(AUX MOTOR) is a spent rocket body associated with Russia (CIS), launched on 2005-03-29 from Baikonur Cosmodrome, Kazakhstan on the Ekspress AM-2 launch. With over 21 years in orbit, it has far exceeded many satellites’ design lifetimes. It orbits in Medium Earth Orbit (MEO) at altitudes between 282 km and 11,550 km with an inclination of 47.3°. It travels at approximately 20,504 km/h (5.70 km/s), completing one full orbit every 3 hours 46 minutes — that’s roughly 6.37 orbits per day. Its orbital eccentricity of 0.4585 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 5,916 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 47.3°, SL-12 R/B(AUX MOTOR) passes over latitudes between 47.3°N and 47.3°S, covering the tropical and temperate zones where most of the world’s population resides. Low-to-mid inclination orbits are efficient to reach from equatorial and mid-latitude launch sites. Russia (CIS) operates approximately 1,514 active satellites in total.