PEGASUS R/B

PEGASUS R/B is a spent rocket body associated with United States, launched on 1995-04-03 from Vandenberg Space Force Base, United States on the Orbcomm FM1 launch. With over 31 years in orbit, it has far exceeded many satellites’ design lifetimes. It orbits in Low Earth Orbit (LEO) at altitudes between 706 km and 724 km with an inclination of 70.0°. It travels at approximately 27,000 km/h (7.50 km/s), completing one full orbit every 99 minutes — that’s roughly 14.53 orbits per day. At its current altitude, the estimated orbital lifetime before atmospheric re-entry is ~25–100 years. Spent rocket bodies like PEGASUS 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.

PEGASUS R/B orbits at an average altitude of 715 km in the mid-LEO band, where atmospheric drag is minimal but radiation exposure remains manageable. Objects at this altitude persist for decades to centuries, making debris mitigation critical. This regime is popular for remote sensing constellations and scientific instruments that need stable, long-duration orbits. Within ±50 km of PEGASUS R/B’s average altitude, there are currently 302 active payloads and 1,795 tracked debris or rocket body fragments — notable neighbours include TERRA, AQUA, ONEWEB-0179. With an inclination of 70.0°, PEGASUS R/B passes over latitudes between 70.0°N and 70.0°S, covering most populated land masses in both hemispheres. This mid-inclination band balances global coverage with efficient launch energy requirements. United States operates approximately 13,200 active satellites in total, of which 96 share a similar altitude band with PEGASUS R/B.