TIANHUI 4B

TIANHUI 4B is an active satellite operated by China, launched on 2021-12-29 from Jiuquan, China. It orbits in Low Earth Orbit (LEO) at altitudes between 420 km and 434 km with an inclination of 89.0°. It travels at approximately 27,566 km/h (7.66 km/s), completing one full orbit every 93 minutes — that’s roughly 15.47 orbits per day. At its current altitude, the estimated orbital lifetime before atmospheric re-entry is ~1–3 years. Orbital Radar tracks TIANHUI 4B in real time using the latest two-line element set (TLE) data, providing live position, altitude, speed and orbital path updated continuously.

TIANHUI 4B orbits at an average altitude of 427 km in the core of Low Earth Orbit, the most heavily utilised altitude band. The balance of moderate drag (limiting debris accumulation) and short signal path (enabling low-latency links and high-resolution imaging) makes this regime the default for most commercial and government missions. Within ±50 km of TIANHUI 4B’s average altitude, there are currently 4,281 active payloads and 141 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 24.6% of all active satellites. With an inclination of 89.0°, TIANHUI 4B passes over latitudes between 89.0°N and 89.0°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 70 share a similar altitude band with TIANHUI 4B.