CZ-4B R/B

CZ-4B R/B is a spent rocket body associated with China, launched on 2020-09-21 from Jiuquan, China on the HY-2C launch. It orbits in Low Earth Orbit (LEO) at altitudes between 648 km and 936 km with an inclination of 66.1°. It travels at approximately 26,855 km/h (7.46 km/s), completing one full orbit every 101 minutes — that’s roughly 14.30 orbits per day. At its current altitude, the estimated orbital lifetime before atmospheric re-entry is ~25–100 years. Spent rocket bodies like CZ-4B 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.

CZ-4B R/B orbits at an average altitude of 792 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 CZ-4B R/B’s average altitude, there are currently 424 active payloads and 2,260 tracked debris or rocket body fragments — notable neighbours include NOAA 20, ONEWEB-0179, ONEWEB-0455. With an inclination of 66.1°, CZ-4B R/B passes over latitudes between 66.1°N and 66.1°S, covering most populated land masses in both hemispheres. This mid-inclination band balances global coverage with efficient launch energy requirements. China operates approximately 1,221 active satellites in total, of which 98 share a similar altitude band with CZ-4B R/B.