KYOKKO 1 DEB

KYOKKO 1 DEB is a tracked piece of space debris attributed to Japan, launched on 1978-02-04 from Uchinoura, Japan on the EXOS-A launch. With over 48 years in orbit, it has far exceeded many satellites’ design lifetimes. It orbits in Medium Earth Orbit (MEO) at altitudes between 634 km and 3,702 km with an inclination of 64.8°. It travels at approximately 24,596 km/h (6.83 km/s), completing one full orbit every 2 hours 11 minutes — that’s roughly 10.99 orbits per day. Its orbital eccentricity of 0.1796 gives it a noticeably elliptical path, with significant altitude variation between perigee and apogee. As orbital debris, KYOKKO 1 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.

KYOKKO 1 DEB orbits at an average altitude of 2,168 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 KYOKKO 1 DEB’s average altitude, there are currently 4 active payloads and 12 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 64.8°, KYOKKO 1 DEB passes over latitudes between 64.8°N and 64.8°S, covering most populated land masses in both hemispheres. This mid-inclination band balances global coverage with efficient launch energy requirements. Japan operates approximately 189 active satellites in total.