GRACE-FO 1

GRACE-FO 1 is an active satellite operated by NASA/German Research Centre for Geosciences (GFZ) (United States), launched on 2018-05-22 from Vandenberg Space Force Base, United States on the Iridium-6/GRACE-FO launch. It orbits in Low Earth Orbit (LEO) at altitudes between 443 km and 448 km with an inclination of 89.0°. It travels at approximately 27,529 km/h (7.65 km/s), completing one full orbit every 93 minutes — that’s roughly 15.40 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 ~1–3 years. Orbital Radar tracks GRACE-FO 1 in real time using the latest two-line element set (TLE) data, providing live position, altitude, speed and orbital path updated continuously.

GRACE-FO 1 orbits at an average altitude of 446 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 GRACE-FO 1’s average altitude, there are currently 10,479 active payloads and 149 tracked debris or rocket body fragments — notable neighbours include ISS (ZARYA), STARLINK-1017, STARLINK-1039. This makes it one of the more crowded altitude bands, containing roughly 55.3% of all active satellites. With an inclination of 89.0°, GRACE-FO 1 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. United States operates approximately 13,342 active satellites in total, of which 10,141 share a similar altitude band with GRACE-FO 1.