SL-23 R/B

SL-23 R/B is a spent rocket body associated with Russia (CIS), launched on 2009-02-26 from Baikonur, Kazakhstan on the Telstar 11N launch. After 17 years in orbit, it continues to be tracked by global surveillance networks. It orbits in Medium Earth Orbit (MEO) at altitudes between 1,341 km and 35,779 km with an inclination of 34.9°. It travels at approximately 14,395 km/h (4.00 km/s), completing one full orbit every 10 hours 53 minutes — that’s roughly 2.20 orbits per day. Its orbital eccentricity of 0.6907 gives it a noticeably elliptical path, with significant altitude variation between perigee and apogee. Spent rocket bodies like SL-23 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-23 R/B orbits at an average altitude of 18,560 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-23 R/B’s average altitude, there are currently 1 active payload and 13 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 34.9°, SL-23 R/B passes over latitudes between 34.9°N and 34.9°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 1,286 active satellites in total.