USA 40 R/B

USA 40 R/B is a spent rocket body associated with United States, launched on 1989-08-08 from Cape Canaveral, Florida on the OV-102 Medium deploy launch. With over 37 years in orbit, it has far exceeded many satellites’ design lifetimes. It orbits in Medium Earth Orbit (MEO) at altitudes between 486 km and 8,075 km with an inclination of 57.0°. It travels at approximately 22,022 km/h (6.12 km/s), completing one full orbit every 3 hours 3 minutes — that’s roughly 7.89 orbits per day. Its orbital eccentricity of 0.3562 gives it a noticeably elliptical path, with significant altitude variation between perigee and apogee. Spent rocket bodies like USA 40 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.

USA 40 R/B orbits at an average altitude of 4,281 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. Within ±50 km of USA 40 R/B’s average altitude, there are currently 0 active payloads and 2 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 57.0°, USA 40 R/B passes over latitudes between 57.0°N and 57.0°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 12,413 active satellites in total.