SL-8 DEB *

SL-8 DEB * is a tracked piece of space debris attributed to Russia (CIS), launched on 1975-09-30 from PKMTR on the Strela-2M launch. After more than 51 years in orbit, it is one of the longest-surviving objects in the space catalogue. It orbits in Low Earth Orbit (LEO) at altitudes between 614 km and 618 km with an inclination of 74.0°. It travels at approximately 27,191 km/h (7.55 km/s), completing one full orbit every 97 minutes — that’s roughly 14.84 orbits per day. Its near-circular orbit (eccentricity close to zero) means it maintains a very consistent altitude throughout each revolution. At its current altitude, the estimated orbital lifetime before atmospheric re-entry is ~10–25 years. As orbital debris, SL-8 DEB * poses a potential collision risk to operational satellites in nearby orbits and is continuously monitored by the U.S. Space Surveillance Network and other tracking systems.

SL-8 DEB * orbits at an average altitude of 616 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 SL-8 DEB *’s average altitude, there are currently 1,559 active payloads and 729 tracked debris or rocket body fragments — notable neighbours include ONEWEB-0050, STARLINK-3090, STARLINK-3077. This makes it one of the more crowded altitude bands, containing roughly 8.9% of all active satellites. With an inclination of 74.0°, SL-8 DEB * passes over latitudes between 74.0°N and 74.0°S, covering most populated land masses in both hemispheres. This mid-inclination band balances global coverage with efficient launch energy requirements. Russia (CIS) operates approximately 1,285 active satellites in total, of which 22 share a similar altitude band with SL-8 DEB *.