DELTA 1 R/B

DELTA 1 R/B is a spent rocket body associated with United States, launched on 1966-02-28 from Cape Canaveral Space Force Station, United States on the Tiros OT2 launch. After more than 60 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 1,351 km and 1,413 km with an inclination of 100.9°. It travels at approximately 25,813 km/h (7.17 km/s), completing one full orbit every 113 minutes — that’s roughly 12.70 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 1,382 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 229 active payloads and 246 tracked debris or rocket body fragments. With an inclination of 100.9°, DELTA 1 R/B passes over latitudes between 100.9°N and 100.9°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 13,206 active satellites in total, of which 10 share a similar altitude band with DELTA 1 R/B.