TANSUO 1

TANSUO 1 is an active satellite operated by China Academy of Space Technology (CAST) (China), launched on 2004-04-18 from Xichang, China. With over 22 years in orbit, it has far exceeded many satellites’ design lifetimes. It orbits in Low Earth Orbit (LEO) at altitudes between 461 km and 468 km with an inclination of 97.9°. It travels at approximately 27,491 km/h (7.64 km/s), completing one full orbit every 94 minutes — that’s roughly 15.34 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. At its current altitude, the estimated orbital lifetime before atmospheric re-entry is ~1–3 years. Orbital Radar tracks TANSUO 1 in real time using the latest two-line element set (TLE) data, providing live position, altitude, speed and orbital path updated continuously.

TANSUO 1 orbits at an average altitude of 465 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 TANSUO 1’s average altitude, there are currently 7,997 active payloads and 179 tracked debris or rocket body fragments — notable neighbours include STARLINK-1008, STARLINK-1012, STARLINK-1017. This makes it one of the more crowded altitude bands, containing roughly 45.9% of all active satellites. With an inclination of 97.9°, TANSUO 1 passes over latitudes between 97.9°N and 97.9°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. China operates approximately 1,219 active satellites in total, of which 164 share a similar altitude band with TANSUO 1.