SL-26 R/B

SL-26 R/B is a spent rocket body associated with Russia (CIS), launched on 2010-11-02 from PKMTR. After 16 years in orbit, it continues to be tracked by global surveillance networks. It orbits in Medium Earth Orbit (MEO) at altitudes between 1,528 km and 38,826 km with an inclination of 63.7°. It travels at approximately 13,949 km/h (3.87 km/s), completing one full orbit every 11 hours 58 minutes — that’s roughly 2.01 orbits per day. Its orbital eccentricity of 0.7025 gives it a noticeably elliptical path, with significant altitude variation between perigee and apogee. Spent rocket bodies like SL-26 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-26 R/B orbits at an average altitude of 20,177 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-26 R/B’s average altitude, there are currently 102 active payloads and 12 tracked debris or rocket body fragments — notable neighbours include GPS BIIR-5 (PRN 22), GPS BIIR-8 (PRN 16), GPS BIIR-11 (PRN 19). With an inclination of 63.7°, SL-26 R/B passes over latitudes between 63.7°N and 63.7°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 1,285 active satellites in total, of which 55 share a similar altitude band with SL-26 R/B.