SL-12 DEB

SL-12 DEB is a tracked piece of space debris attributed to Russia (CIS), launched on 1989-05-31 from Baikonur, Kazakhstan on the Uragan No. 28L launch. With over 37 years in orbit, it has far exceeded many satellites’ design lifetimes. It orbits in Medium Earth Orbit (MEO) at altitudes between 19,069 km and 19,174 km with an inclination of 64.9°. It travels at approximately 14,235 km/h (3.95 km/s), completing one full orbit every 11 hours 15 minutes — that’s roughly 2.13 orbits per day. As orbital debris, SL-12 DEB poses a potential collision risk to operational satellites in nearby orbits and is continuously monitored by the U.S. Space Surveillance Network and other tracking systems.

SL-12 DEB orbits at an average altitude of 19,122 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 DEB’s average altitude, there are currently 142 active payloads and 46 tracked debris or rocket body fragments — notable neighbours include COSMOS 1414 (GLONASS), COSMOS 1415 (GLONASS), COSMOS 1490 (GLONASS). With an inclination of 64.9°, SL-12 DEB passes over latitudes between 64.9°N and 64.9°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 142 share a similar altitude band with SL-12 DEB.