SCOUT X-4 DEB

SCOUT X-4 DEB is a tracked piece of space debris attributed to United States, launched on 1963-12-19 from Vandenberg Space Force Base, United States on the AD-A launch. After more than 63 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 582 km and 1,139 km with an inclination of 78.5°. It travels at approximately 26,727 km/h (7.42 km/s), completing one full orbit every 102 minutes — that’s roughly 14.10 orbits per day. At its current altitude, the estimated orbital lifetime before atmospheric re-entry is ~100–500 years. As orbital debris, SCOUT X-4 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.

SCOUT X-4 DEB orbits at an average altitude of 861 km in the upper LEO band, where atmospheric drag is negligible and objects can persist for centuries to millennia. This altitude is used by broadband constellations like OneWeb and by scientific missions requiring stable orbits far from the densest debris bands. Within ±50 km of SCOUT X-4 DEB’s average altitude, there are currently 255 active payloads and 2,213 tracked debris or rocket body fragments — notable neighbours include NOAA 20, ONEWEB-0455. With an inclination of 78.5°, SCOUT X-4 DEB passes over latitudes between 78.5°N and 78.5°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 13,342 active satellites in total, of which 73 share a similar altitude band with SCOUT X-4 DEB.