COSMOS 939

COSMOS 939 is an active satellite operated by Russia (CIS), launched on 1977-08-24 from PKMTR. With over 49 years in orbit, it has far exceeded many satellites’ design lifetimes. It orbits in Low Earth Orbit (LEO) at altitudes between 1,432 km and 1,461 km with an inclination of 74.0°. It travels at approximately 25,706 km/h (7.14 km/s), completing one full orbit every 115 minutes — that’s roughly 12.54 orbits per day. At its current altitude, the estimated orbital lifetime before atmospheric re-entry is thousands of years. Orbital Radar tracks COSMOS 939 in real time using the latest two-line element set (TLE) data, providing live position, altitude, speed and orbital path updated continuously.

COSMOS 939 orbits at an average altitude of 1,447 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 939’s average altitude, there are currently 443 active payloads and 209 tracked debris or rocket body fragments. With an inclination of 74.0°, COSMOS 939 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 1,285 active satellites in total, of which 405 share a similar altitude band with COSMOS 939.