SL-8 DEB

SL-8 DEB is a tracked piece of space debris attributed to Russia (CIS), launched on 1991-02-12 from PKMTR. With over 35 years in orbit, it has far exceeded many satellites’ design lifetimes. It orbits in Low Earth Orbit (LEO) at altitudes between 1,439 km and 1,671 km with an inclination of 73.9°. It travels at approximately 25,530 km/h (7.09 km/s), completing one full orbit every 117 minutes — that’s roughly 12.29 orbits per day. At its current altitude, the estimated orbital lifetime before atmospheric re-entry is thousands of years. As orbital debris, SL-8 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-8 DEB orbits at an average altitude of 1,555 km in the uppermost reaches of Low Earth Orbit. At this altitude, orbital decay is effectively zero without active deorbiting, and coverage footprints are significantly larger than lower LEO, though at the cost of higher latency. Within ±50 km of SL-8 DEB’s average altitude, there are currently 34 active payloads and 221 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 73.9°, SL-8 DEB passes over latitudes between 73.9°N and 73.9°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 1,286 active satellites in total, of which 20 share a similar altitude band with SL-8 DEB.