PEGASUS R/B

PEGASUS R/B is a spent rocket body associated with United States, launched on 2003-01-25 from Esrange, Sweden on the SORCE launch. With over 23 years in orbit, it has far exceeded many satellites’ design lifetimes. It orbits in Low Earth Orbit (LEO) at altitudes between 571 km and 596 km with an inclination of 40.0°. It travels at approximately 27,255 km/h (7.57 km/s), completing one full orbit every 96 minutes — that’s roughly 14.95 orbits per day. At its current altitude, the estimated orbital lifetime before atmospheric re-entry is ~3–10 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 584 km in the core of Low Earth Orbit, the most heavily utilised altitude band. The balance of moderate drag (limiting debris accumulation) and short signal path (enabling low-latency links and high-resolution imaging) makes this regime the default for most commercial and government missions. Within ±50 km of PEGASUS R/B’s average altitude, there are currently 3,063 active payloads and 572 tracked debris or rocket body fragments — notable neighbours include ONEWEB-0050, STARLINK-3005, STARLINK-3090. This makes it one of the more crowded altitude bands, containing roughly 17.5% of all active satellites. With an inclination of 40.0°, PEGASUS R/B passes over latitudes between 40.0°N and 40.0°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 2,513 share a similar altitude band with PEGASUS R/B.