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 814 km and 1,713 km with an inclination of 55.5°. It travels at approximately 26,012 km/h (7.23 km/s), completing one full orbit every 111 minutes — that’s roughly 13.00 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 1,264 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 143 active payloads and 378 tracked debris or rocket body fragments — notable neighbours include ONEWEB-0013, ONEWEB-0017, ONEWEB-0020. With an inclination of 55.5°, SL-8 DEB passes over latitudes between 55.5°N and 55.5°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 5 share a similar altitude band with SL-8 DEB.