GALEX

GALEX is an active satellite operated by United States, launched on 2003-04-28 from Cape Canaveral, Florida. With over 23 years in orbit, it has far exceeded many satellites’ design lifetimes. It orbits in Low Earth Orbit (LEO) at altitudes between 671 km and 676 km with an inclination of 29.0°. It travels at approximately 27,080 km/h (7.52 km/s), completing one full orbit every 98 minutes — that’s roughly 14.66 orbits per day. 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 ~10–25 years. Orbital Radar tracks GALEX in real time using the latest two-line element set (TLE) data, providing live position, altitude, speed and orbital path updated continuously.

GALEX orbits at an average altitude of 674 km in the mid-LEO band, where atmospheric drag is minimal but radiation exposure remains manageable. Objects at this altitude persist for decades to centuries, making debris mitigation critical. This regime is popular for remote sensing constellations and scientific instruments that need stable, long-duration orbits. Within ±50 km of GALEX’s average altitude, there are currently 559 active payloads and 1,234 tracked debris or rocket body fragments — notable neighbours include TERRA, AQUA, LANDSAT 9. With an inclination of 29.0°, GALEX passes over latitudes between 29.0°N and 29.0°S, covering the tropical and temperate zones where most of the world’s population resides. Low-to-mid inclination orbits are efficient to reach from equatorial and mid-latitude launch sites. United States operates approximately 12,360 active satellites in total, of which 274 share a similar altitude band with GALEX.