ATLAS 55E DEB

ATLAS 55E DEB is a tracked piece of space debris attributed to United States, launched on 1985-10-09 from Vandenberg SFB, California. With over 41 years in orbit, it has far exceeded many satellites’ design lifetimes. It orbits in Medium Earth Orbit (MEO) at altitudes between 429 km and 20,896 km with an inclination of 62.9°. It travels at approximately 17,415 km/h (4.84 km/s), completing one full orbit every 6 hours 9 minutes — that’s roughly 3.90 orbits per day. Its orbital eccentricity of 0.6008 gives it a noticeably elliptical path, with significant altitude variation between perigee and apogee. As orbital debris, ATLAS 55E 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.

ATLAS 55E DEB orbits at an average altitude of 10,663 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 ATLAS 55E DEB’s average altitude, there are currently 0 active payloads and 6 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 62.9°, ATLAS 55E DEB passes over latitudes between 62.9°N and 62.9°S, covering most populated land masses in both hemispheres. This mid-inclination band balances global coverage with efficient launch energy requirements. United States operates approximately 12,360 active satellites in total.