SHIYAN 25 (SY-25)

SHIYAN 25 (SY-25) is an active satellite operated by China, launched on 2023-06-20 from Taiyuan, China. It orbits in Low Earth Orbit (LEO) at altitudes between 267 km and 277 km with an inclination of 96.8°. It travels at approximately 27,886 km/h (7.75 km/s), completing one full orbit every 90 minutes — that’s roughly 16.01 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 weeks to months. Orbital Radar tracks SHIYAN 25 (SY-25) in real time using the latest two-line element set (TLE) data, providing live position, altitude, speed and orbital path updated continuously.

SHIYAN 25 (SY-25) orbits at an average altitude of 272 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 SHIYAN 25 (SY-25)’s average altitude, there are currently 169 active payloads and 5 tracked debris or rocket body fragments — notable neighbours include STARLINK-1151, STARLINK-1143, STARLINK-1280. With an inclination of 96.8°, SHIYAN 25 (SY-25) passes over latitudes between 96.8°N and 96.8°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 4 share a similar altitude band with SHIYAN 25 (SY-25).