ETS 6 DEB

ETS 6 DEB is a tracked piece of space debris attributed to Japan, launched on 1994-08-28 from TNSTA on the ETS-6 launch. With over 32 years in orbit, it has far exceeded many satellites’ design lifetimes. It orbits in Medium Earth Orbit (MEO) at altitudes between 7,945 km and 38,540 km with an inclination of 12.0°. It travels at approximately 13,208 km/h (3.67 km/s), completing one full orbit every 14 hours 6 minutes — that’s roughly 1.70 orbits per day. Its orbital eccentricity of 0.5166 gives it a noticeably elliptical path, with significant altitude variation between perigee and apogee. As orbital debris, ETS 6 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.

ETS 6 DEB orbits at an average altitude of 23,243 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 ETS 6 DEB’s average altitude, there are currently 30 active payloads and 3 tracked debris or rocket body fragments — notable neighbours include GALILEO-PFM, GALILEO-FM2, GALILEO-FM3. This is a relatively sparse altitude band, containing less than 1% of all active satellites. With an inclination of 12.0°, ETS 6 DEB passes over latitudes between 12.0°N and 12.0°S, concentrating coverage over equatorial and near-equatorial regions. Low-inclination orbits maximise revisit rates over specific tropical zones. Japan operates approximately 189 active satellites in total.