COSMOS 397 DEB

COSMOS 397 DEB is a tracked piece of space debris attributed to Russia (CIS), launched on 1971-02-25 from Baikonur, Kazakhstan. After more than 55 years in orbit, it is one of the longest-surviving objects in the space catalogue. It orbits in Low Earth Orbit (LEO) at altitudes between 474 km and 723 km with an inclination of 65.7°. It travels at approximately 27,225 km/h (7.56 km/s), completing one full orbit every 97 minutes — that’s roughly 14.90 orbits per day. At its current altitude, the estimated orbital lifetime before atmospheric re-entry is ~3–10 years. As orbital debris, COSMOS 397 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 397 DEB orbits at an average altitude of 599 km in the core of Low Earth Orbit, the most heavily utilised altitude band. The balance of moderate drag (limiting debris accumulation) and short signal path (enabling low-latency links and high-resolution imaging) makes this regime the default for most commercial and government missions. Within ±50 km of COSMOS 397 DEB’s average altitude, there are currently 2,106 active payloads and 644 tracked debris or rocket body fragments — notable neighbours include ONEWEB-0050, STARLINK-3005, STARLINK-3090. This makes it one of the more crowded altitude bands, containing roughly 12.1% of all active satellites. With an inclination of 65.7°, COSMOS 397 DEB 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 1,286 active satellites in total, of which 25 share a similar altitude band with COSMOS 397 DEB.