COSMOS 917 DEB

COSMOS 917 DEB is a tracked piece of space debris attributed to Russia (CIS), launched on 1977-06-16 from PKMTR. With over 49 years in orbit, it has far exceeded many satellites’ design lifetimes. It orbits in Medium Earth Orbit (MEO) at altitudes between 387 km and 39,753 km with an inclination of 59.9°. It travels at approximately 13,978 km/h (3.88 km/s), completing one full orbit every 11 hours 53 minutes — that’s roughly 2.02 orbits per day. Its orbital eccentricity of 0.7444 gives it a noticeably elliptical path, with significant altitude variation between perigee and apogee. As orbital debris, COSMOS 917 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 917 DEB orbits at an average altitude of 20,070 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 917 DEB’s average altitude, there are currently 3 active payloads and 22 tracked debris or rocket body fragments. This is a relatively sparse altitude band, containing less than 1% of all active satellites. With an inclination of 59.9°, COSMOS 917 DEB passes over latitudes between 59.9°N and 59.9°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 2 share a similar altitude band with COSMOS 917 DEB.