COSMOS 2251 DEB

COSMOS 2251 DEB is a tracked piece of space debris attributed to Russia (CIS), launched on 1993-06-16 from Plesetsk Cosmodrome, Russia on the Strela-2M launch. With over 33 years in orbit, it has far exceeded many satellites’ design lifetimes. It orbits in Low Earth Orbit (LEO) at altitudes between 266 km and 294 km with an inclination of 74.0°. It travels at approximately 27,869 km/h (7.74 km/s), completing one full orbit every 90 minutes — that’s roughly 15.98 orbits per day. At its current altitude, the estimated orbital lifetime before atmospheric re-entry is weeks to months. As orbital debris, COSMOS 2251 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.

COSMOS 2251 DEB orbits at an average altitude of 280 km in the lower reaches of Low Earth Orbit, where atmospheric drag is significant and orbital lifetimes are measured in months to a few years. This is the busiest corridor in space — home to crewed spacecraft, rapid-revisit imaging satellites and the densest part of the Starlink constellation. Within ±50 km of COSMOS 2251 DEB’s average altitude, there are currently 147 active payloads and 15 tracked debris or rocket body fragments — notable neighbours include STARLINK-1036, STARLINK-1048, STARLINK-1114. With an inclination of 74.0°, COSMOS 2251 DEB passes over latitudes between 74.0°N and 74.0°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 1,525 active satellites in total, of which 14 share a similar altitude band with COSMOS 2251 DEB.