SL-8 DEB

SL-8 DEB is a tracked piece of space debris attributed to Russia (CIS), launched on 1965-09-18 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 1,367 km and 1,728 km with an inclination of 56.2°. It travels at approximately 25,542 km/h (7.09 km/s), completing one full orbit every 117 minutes — that’s roughly 12.30 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 1,548 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 77 active payloads and 383 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 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 1,535 active satellites in total, of which 60 share a similar altitude band with SL-8 DEB.