CUBESAT XI 4

CUBESAT XI 4 is an active satellite operated by Department of Astronautics, University of Tokyo (Japan), launched on 2003-06-30 from PKMTR. With over 23 years in orbit, it has far exceeded many satellites’ design lifetimes. It orbits in Low Earth Orbit (LEO) at altitudes between 807 km and 820 km with an inclination of 98.7°. It travels at approximately 26,815 km/h (7.45 km/s), completing one full orbit every 101 minutes — that’s roughly 14.24 orbits per day. Its near-polar, sun-synchronous orbit means it passes over any given point on Earth at approximately the same local solar time, ideal for consistent Earth observation lighting conditions. Its near-circular orbit (eccentricity close to zero) means it maintains a very consistent altitude throughout each revolution. It is part of the Cubesat constellation group. At its current altitude, the estimated orbital lifetime before atmospheric re-entry is ~100–500 years. Orbital Radar tracks CUBESAT XI 4 in real time using the latest two-line element set (TLE) data, providing live position, altitude, speed and orbital path updated continuously.

CUBESAT XI 4 orbits at an average altitude of 814 km in a sun-synchronous orbit (SSO), a specialised subset of LEO where the orbital plane precesses to maintain a constant angle relative to the Sun. This provides consistent lighting conditions on every pass — essential for Earth observation, weather monitoring and environmental science. Within ±50 km of CUBESAT XI 4’s average altitude, there are currently 419 active payloads and 2,319 tracked debris or rocket body fragments — notable neighbours include NOAA 20, ONEWEB-0179, ONEWEB-0455. With an inclination of 98.7°, CUBESAT XI 4 passes over latitudes between 98.7°N and 98.7°S, providing near-global coverage including the polar regions. Polar and near-polar orbits are used for reconnaissance, weather monitoring and Earth-observation missions that need to image every part of the planet. Japan operates approximately 189 active satellites in total, of which 9 share a similar altitude band with CUBESAT XI 4.