SL-8 DEB

SL-8 DEB is a tracked piece of space debris attributed to Russia (CIS), launched on 1965-03-15 from Baikonur Cosmodrome, Kazakhstan on the Strela-1 launch. After more than 61 years in orbit, it is one of the longest-surviving objects in the space catalogue. It orbits in Low Earth Orbit (LEO) at altitudes between 542 km and 1,086 km with an inclination of 56.2°. It travels at approximately 26,814 km/h (7.45 km/s), completing one full orbit every 101 minutes — that’s roughly 14.23 orbits per day. At its current altitude, the estimated orbital lifetime before atmospheric re-entry is ~100–500 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 814 km in the upper LEO band, where atmospheric drag is negligible and objects can persist for centuries to millennia. This altitude is used by broadband constellations like OneWeb and by scientific missions requiring stable orbits far from the densest debris bands. Within ±50 km of SL-8 DEB’s average altitude, there are currently 454 active payloads and 2,519 tracked debris or rocket body fragments — notable neighbours include NOAA 20, ONEWEB-0455. With an inclination of 56.2°, SL-8 DEB passes over latitudes between 56.2°N and 56.2°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 1,537 active satellites in total, of which 112 share a similar altitude band with SL-8 DEB.