COSMOS 931

COSMOS 931 is an active satellite operated by PVO (Russia (CIS)), launched on 1977-07-20 from Plesetsk Cosmodrome, Russia on the Oko launch. With over 49 years in orbit, it has far exceeded many satellites’ design lifetimes. It orbits in Medium Earth Orbit (MEO) at altitudes between 6,105 km and 34,232 km with an inclination of 71.2°. It travels at approximately 13,952 km/h (3.88 km/s), completing one full orbit every 11 hours 57 minutes — that’s roughly 2.01 orbits per day. Its orbital eccentricity of 0.5299 gives it a noticeably elliptical path, with significant altitude variation between perigee and apogee. Orbital Radar tracks COSMOS 931 in real time using the latest two-line element set (TLE) data, providing live position, altitude, speed and orbital path updated continuously.

COSMOS 931 orbits at an average altitude of 20,169 km in Medium Earth Orbit, the region between LEO and GEO (2,000–35,786 km). MEO’s higher altitude gives each satellite a much larger ground footprint than LEO, meaning fewer spacecraft are needed for global coverage — but signal latency is higher and radiation from the Van Allen belts is a significant design constraint. Within ±50 km of COSMOS 931’s average altitude, there are currently 105 active payloads and 11 tracked debris or rocket body fragments. With an inclination of 71.2°, COSMOS 931 passes over latitudes between 71.2°N and 71.2°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 1,547 active satellites in total, of which 56 share a similar altitude band with COSMOS 931.