DELTA 2 R/B(1)

DELTA 2 R/B(1) is a spent rocket body associated with United States, launched on 1998-06-10 from Cape Canaveral, Florida on the Thor 3 launch. With over 28 years in orbit, it has far exceeded many satellites’ design lifetimes. It orbits in Low Earth Orbit (LEO) at altitudes between 890 km and 1,677 km with an inclination of 26.4°. It travels at approximately 25,978 km/h (7.22 km/s), completing one full orbit every 111 minutes — that’s roughly 12.95 orbits per day. At its current altitude, the estimated orbital lifetime before atmospheric re-entry is thousands of years. Spent rocket bodies like DELTA 2 R/B(1) 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(1) orbits at an average altitude of 1,284 km in the uppermost reaches of Low Earth Orbit. At this altitude, orbital decay is effectively zero without active deorbiting, and coverage footprints are significantly larger than lower LEO, though at the cost of higher latency. Within ±50 km of DELTA 2 R/B(1)’s average altitude, there are currently 13 active payloads and 288 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 26.4°, DELTA 2 R/B(1) passes over latitudes between 26.4°N and 26.4°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 4 share a similar altitude band with DELTA 2 R/B(1).