STELLA

STELLA is an active satellite operated by France, launched on 1993-09-26 from Guiana Space Centre, Kourou. With over 33 years in orbit, it has far exceeded many satellites’ design lifetimes. It orbits in Low Earth Orbit (LEO) at altitudes between 796 km and 804 km with an inclination of 98.8°. It travels at approximately 26,840 km/h (7.46 km/s), completing one full orbit every 101 minutes — that’s roughly 14.27 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 ~100–500 years. Orbital Radar tracks STELLA in real time using the latest two-line element set (TLE) data, providing live position, altitude, speed and orbital path updated continuously.

STELLA orbits at an average altitude of 800 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 STELLA’s average altitude, there are currently 439 active payloads and 2,266 tracked debris or rocket body fragments — notable neighbours include NOAA 20, ONEWEB-0179, ONEWEB-0455. With an inclination of 98.8°, STELLA passes over latitudes between 98.8°N and 98.8°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. France operates approximately 115 active satellites in total, of which 3 share a similar altitude band with STELLA.