COSMOS 1691 DEB

COSMOS 1691 DEB is a tracked piece of space debris attributed to Russia (CIS), launched on 1985-10-09 from PKMTR. With over 41 years in orbit, it has far exceeded many satellites’ design lifetimes. It orbits in Low Earth Orbit (LEO) at altitudes between 1,368 km and 1,716 km with an inclination of 83.2°. It travels at approximately 25,551 km/h (7.10 km/s), completing one full orbit every 117 minutes — that’s roughly 12.32 orbits per day. At its current altitude, the estimated orbital lifetime before atmospheric re-entry is thousands of years. As orbital debris, COSMOS 1691 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 1691 DEB orbits at an average altitude of 1,542 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 COSMOS 1691 DEB’s average altitude, there are currently 115 active payloads and 266 tracked debris or rocket body fragments. With an inclination of 83.2°, COSMOS 1691 DEB passes over latitudes between 83.2°N and 83.2°S, providing near-global coverage including the polar regions. Polar and near-polar orbits are used for reconnaissance, weather monitoring and Earth-observation missions that need to image every part of the planet. Russia (CIS) operates approximately 1,286 active satellites in total, of which 102 share a similar altitude band with COSMOS 1691 DEB.