SL-12 R/B(2)

SL-12 R/B(2) is a spent rocket body associated with Russia (CIS), launched on 1984-05-19 from Baikonur, Kazakhstan on the Uragan No. 16L launch. With over 42 years in orbit, it has far exceeded many satellites’ design lifetimes. It orbits in Medium Earth Orbit (MEO) at altitudes between 19,101 km and 19,149 km with an inclination of 66.4°. It travels at approximately 14,234 km/h (3.95 km/s), completing one full orbit every 11 hours 16 minutes — that’s roughly 2.13 orbits per day. Spent rocket bodies like SL-12 R/B(2) 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(2) orbits at an average altitude of 19,125 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(2)’s average altitude, there are currently 141 active payloads and 47 tracked debris or rocket body fragments — notable neighbours include COSMOS 1414 (GLONASS), COSMOS 1490 (GLONASS), COSMOS 1492 (GLONASS). With an inclination of 66.4°, SL-12 R/B(2) passes over latitudes between 66.4°N and 66.4°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 141 share a similar altitude band with SL-12 R/B(2).