KZ-11 R/B

KZ-11 R/B is a spent rocket body associated with China, launched on 2026-06-17 from Jiuquan, China on the Centispace 05 launch. As a relatively recent addition to the catalogue, its orbital elements are well-characterised. It orbits in Low Earth Orbit (LEO) at altitudes between 172 km and 465 km with an inclination of 55.1°. It travels at approximately 27,789 km/h (7.72 km/s), completing one full orbit every 91 minutes — that’s roughly 15.85 orbits per day. At its current altitude, the estimated orbital lifetime before atmospheric re-entry is months to ~1 year. Spent rocket bodies like KZ-11 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.

KZ-11 R/B orbits at an average altitude of 319 km in the lower reaches of Low Earth Orbit, where atmospheric drag is significant and orbital lifetimes are measured in months to a few years. This is the busiest corridor in space — home to crewed spacecraft, rapid-revisit imaging satellites and the densest part of the Starlink constellation. Within ±50 km of KZ-11 R/B’s average altitude, there are currently 1,049 active payloads and 35 tracked debris or rocket body fragments — notable neighbours include STARLINK-1036, STARLINK-1043, STARLINK-1048. This makes it one of the more crowded altitude bands, containing roughly 5.9% of all active satellites. With an inclination of 55.1°, KZ-11 R/B passes over latitudes between 55.1°N and 55.1°S, covering most populated land masses in both hemispheres. This mid-inclination band balances global coverage with efficient launch energy requirements. China operates approximately 1,247 active satellites in total, of which 10 share a similar altitude band with KZ-11 R/B.