SL-12 DEB

SL-12 DEB is a tracked piece of space debris attributed to Russia (CIS), launched on 1999-05-20 from Baikonur, Kazakhstan on the Telesat DTH-1 launch. With over 27 years in orbit, it has far exceeded many satellites’ design lifetimes. It orbits in Medium Earth Orbit (MEO) at altitudes between 16,148 km and 36,737 km with an inclination of 7.3°. It travels at approximately 12,547 km/h (3.49 km/s), completing one full orbit every 16 hours 26 minutes — that’s roughly 1.46 orbits per day. Its orbital eccentricity of 0.3137 gives it a noticeably elliptical path, with significant altitude variation between perigee and apogee. As orbital debris, SL-12 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-12 DEB orbits at an average altitude of 26,443 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 SL-12 DEB’s average altitude, there are currently 0 active payloads and 3 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 7.3°, SL-12 DEB passes over latitudes between 7.3°N and 7.3°S, concentrating coverage over equatorial and near-equatorial regions. Low-inclination orbits maximise revisit rates over specific tropical zones. Russia (CIS) operates approximately 1,285 active satellites in total.