COSMOS 2251 DEB

COSMOS 2251 DEB is a tracked piece of space debris attributed to Russia (CIS), launched on 1993-06-16 from PKMTR 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 390 km and 413 km with an inclination of 73.7°. It travels at approximately 27,618 km/h (7.67 km/s), completing one full orbit every 93 minutes — that’s roughly 15.55 orbits per day. At its current altitude, the estimated orbital lifetime before atmospheric re-entry is ~1–3 years. 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 402 km in the core of Low Earth Orbit, the most heavily utilised altitude band. The balance of moderate drag (limiting debris accumulation) and short signal path (enabling low-latency links and high-resolution imaging) makes this regime the default for most commercial and government missions. Within ±50 km of COSMOS 2251 DEB’s average altitude, there are currently 1,344 active payloads and 98 tracked debris or rocket body fragments — notable neighbours include STARLINK-1008, STARLINK-1012, STARLINK-1020. This makes it one of the more crowded altitude bands, containing roughly 7.7% of all active satellites. With an inclination of 73.7°, COSMOS 2251 DEB passes over latitudes between 73.7°N and 73.7°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 1,287 active satellites in total, of which 33 share a similar altitude band with COSMOS 2251 DEB.