DELTA 1 R/B

DELTA 1 R/B is a spent rocket body associated with United States, launched on 1960-08-12 from Cape Canaveral Space Force Station, United States. After more than 66 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 1,501 km and 1,683 km with an inclination of 47.2°. It travels at approximately 25,470 km/h (7.08 km/s), completing one full orbit every 118 minutes — that’s roughly 12.20 orbits per day. At its current altitude, the estimated orbital lifetime before atmospheric re-entry is thousands of years. Spent rocket bodies like DELTA 1 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 1 R/B orbits at an average altitude of 1,592 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 1 R/B’s average altitude, there are currently 37 active payloads and 286 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 47.2°, DELTA 1 R/B passes over latitudes between 47.2°N and 47.2°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 13,206 active satellites in total, of which 3 share a similar altitude band with DELTA 1 R/B.