IUS R/B(2)

IUS R/B(2) is a spent rocket body associated with United States, launched on 1983-04-04 from Cape Canaveral, Florida on the OV-099 IUS deploy launch. With over 43 years in orbit, it has far exceeded many satellites’ design lifetimes. It orbits in Medium Earth Orbit (MEO) at altitudes between 21,974 km and 35,422 km with an inclination of 4.6°. It travels at approximately 12,137 km/h (3.37 km/s), completing one full orbit every 18 hours 10 minutes — that’s roughly 1.32 orbits per day. Its orbital eccentricity of 0.1917 gives it a noticeably elliptical path, with significant altitude variation between perigee and apogee. Spent rocket bodies like IUS R/B(2) are among the largest pieces of uncontrolled space debris and are priority targets for collision avoidance manoeuvres and future active debris removal efforts.

IUS R/B(2) orbits at an average altitude of 28,698 km in Medium Earth Orbit, the region between LEO and GEO (2,000–35,786 km). MEO’s higher altitude gives each satellite a much larger ground footprint than LEO, meaning fewer spacecraft are needed for global coverage — but signal latency is higher and radiation from the Van Allen belts is a significant design constraint. With an inclination of 4.6°, IUS R/B(2) passes over latitudes between 4.6°N and 4.6°S, concentrating coverage over equatorial and near-equatorial regions. Low-inclination orbits maximise revisit rates over specific tropical zones. United States operates approximately 12,413 active satellites in total.