SL-12 R/B(2)

SL-12 R/B(2) is a spent rocket body associated with Russia (CIS), launched on 1997-06-06 from Baikonur, Kazakhstan on the Arkon 11F664 No. 1 launch. With over 29 years in orbit, it has far exceeded many satellites’ design lifetimes. It orbits in Medium Earth Orbit (MEO) at altitudes between 1,197 km and 3,053 km with an inclination of 63.3°. It travels at approximately 24,658 km/h (6.85 km/s), completing one full orbit every 2 hours 10 minutes — that’s roughly 11.07 orbits per day. Its orbital eccentricity of 0.1092 gives it a noticeably elliptical path, with significant altitude variation between perigee and apogee. 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 2,125 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 7 active payloads and 6 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 63.3°, SL-12 R/B(2) passes over latitudes between 63.3°N and 63.3°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.