COSMOS 397

COSMOS 397 is an active satellite operated by PKO (Russia (CIS)), launched on 1971-02-25 from Baikonur Cosmodrome, Kazakhstan on the I2P launch. After more than 55 years in orbit, it is one of the longest-surviving objects in the space catalogue. It orbits in Medium Earth Orbit (MEO) at altitudes between 567 km and 2,156 km with an inclination of 65.7°. It travels at approximately 25,847 km/h (7.18 km/s), completing one full orbit every 113 minutes — that’s roughly 12.75 orbits per day. Its orbital eccentricity of 0.1027 gives it a noticeably elliptical path, with significant altitude variation between perigee and apogee. At its current altitude, the estimated orbital lifetime before atmospheric re-entry is thousands of years. Orbital Radar tracks COSMOS 397 in real time using the latest two-line element set (TLE) data, providing live position, altitude, speed and orbital path updated continuously.

COSMOS 397 orbits at an average altitude of 1,362 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 397’s average altitude, there are currently 138 active payloads and 248 tracked debris or rocket body fragments. With an inclination of 65.7°, COSMOS 397 passes over latitudes between 65.7°N and 65.7°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 1,553 active satellites in total, of which 115 share a similar altitude band with COSMOS 397.