DELTA 1 DEB

DELTA 1 DEB is a tracked piece of space debris attributed to United States, launched on 1972-07-23 from Vandenberg Space Force Base, United States on the ERTS A launch. After more than 54 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 715 km and 2,014 km with an inclination of 97.4°. It travels at approximately 25,842 km/h (7.18 km/s), completing one full orbit every 113 minutes — that’s roughly 12.74 orbits per day. At its current altitude, the estimated orbital lifetime before atmospheric re-entry is thousands of years. As orbital debris, DELTA 1 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.

DELTA 1 DEB orbits at an average altitude of 1,365 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 DELTA 1 DEB’s average altitude, there are currently 184 active payloads and 250 tracked debris or rocket body fragments. With an inclination of 97.4°, DELTA 1 DEB passes over latitudes between 97.4°N and 97.4°S, providing near-global coverage including the polar regions. Polar and near-polar orbits are used for reconnaissance, weather monitoring and Earth-observation missions that need to image every part of the planet. United States operates approximately 13,196 active satellites in total, of which 12 share a similar altitude band with DELTA 1 DEB.