COSMOS 921

COSMOS 921 is an active satellite operated by Russia (CIS), launched on 1977-06-24 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 553 km and 601 km with an inclination of 75.8°. It travels at approximately 27,267 km/h (7.57 km/s), completing one full orbit every 96 minutes — that’s roughly 14.97 orbits per day. At its current altitude, the estimated orbital lifetime before atmospheric re-entry is ~3–10 years. Orbital Radar tracks COSMOS 921 in real time using the latest two-line element set (TLE) data, providing live position, altitude, speed and orbital path updated continuously.

COSMOS 921 orbits in the most densely populated region of Low Earth Orbit, between roughly 300 and 600 km altitude. This band is home to the International Space Station, most Earth observation satellites, and the bulk of the Starlink constellation. Objects here experience measurable atmospheric drag, which gradually lowers their orbit over months to years and eventually causes re-entry. The relatively short signal path makes this altitude ideal for low-latency communications and high-resolution imaging.