DELTA 2 R/B

DELTA 2 R/B is a spent rocket body associated with United States, launched on 1991-05-29 from Cape Canaveral, Florida on the Satcom C-5 launch. With over 35 years in orbit, it has far exceeded many satellites’ design lifetimes. It orbits in Low Earth Orbit (LEO) at altitudes between 384 km and 1,525 km with an inclination of 25.0°. It travels at approximately 26,555 km/h (7.38 km/s), completing one full orbit every 104 minutes — that’s roughly 13.83 orbits per day. At its current altitude, the estimated orbital lifetime before atmospheric re-entry is ~100–500 years. Spent rocket bodies like DELTA 2 R/B are among the largest pieces of uncontrolled space debris and are priority targets for collision avoidance manoeuvres and future active debris removal efforts.

DELTA 2 R/B orbits at an average altitude of 955 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 DELTA 2 R/B’s average altitude, there are currently 330 active payloads and 1,090 tracked debris or rocket body fragments. With an inclination of 25.0°, DELTA 2 R/B passes over latitudes between 25.0°N and 25.0°S, covering the tropical and temperate zones where most of the world’s population resides. Low-to-mid inclination orbits are efficient to reach from equatorial and mid-latitude launch sites. United States operates approximately 12,413 active satellites in total, of which 91 share a similar altitude band with DELTA 2 R/B.