THOR AGENA B DEB

THOR AGENA B DEB is a tracked piece of space debris attributed to United States, launched on 1965-11-29 from Vandenberg Space Force Base, United States on the Alouette 2 launch. After more than 61 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 499 km and 2,519 km with an inclination of 79.8°. It travels at approximately 25,604 km/h (7.11 km/s), completing one full orbit every 116 minutes — that’s roughly 12.39 orbits per day. Its orbital eccentricity of 0.1282 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. As orbital debris, THOR AGENA B 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.

THOR AGENA B DEB orbits at an average altitude of 1,509 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 THOR AGENA B DEB’s average altitude, there are currently 286 active payloads and 395 tracked debris or rocket body fragments. With an inclination of 79.8°, THOR AGENA B DEB passes over latitudes between 79.8°N and 79.8°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 13,196 active satellites in total, of which 3 share a similar altitude band with THOR AGENA B DEB.