FAST

FAST is an active satellite operated by United States, launched on 1996-08-21 from Vandenberg SFB, California. With over 30 years in orbit, it has far exceeded many satellites’ design lifetimes. It orbits in Medium Earth Orbit (MEO) at altitudes between 345 km and 3,170 km with an inclination of 83.0°. It travels at approximately 25,210 km/h (7.00 km/s), completing one full orbit every 2 hours 2 minutes — that’s roughly 11.83 orbits per day. Its orbital eccentricity of 0.1738 gives it a noticeably elliptical path, with significant altitude variation between perigee and apogee. At its current altitude, the estimated orbital lifetime before atmospheric re-entry is thousands of years. Orbital Radar tracks FAST in real time using the latest two-line element set (TLE) data, providing live position, altitude, speed and orbital path updated continuously.

FAST orbits at an average altitude of 1,758 km in Medium Earth Orbit, the region between LEO and GEO (2,000–35,786 km). MEO’s higher altitude gives each satellite a much larger ground footprint than LEO, meaning fewer spacecraft are needed for global coverage — but signal latency is higher and radiation from the Van Allen belts is a significant design constraint. Within ±50 km of FAST’s average altitude, there are currently 9 active payloads and 26 tracked debris or rocket body fragments. This is a relatively sparse altitude band, containing less than 1% of all active satellites. With an inclination of 83.0°, FAST passes over latitudes between 83.0°N and 83.0°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 12,339 active satellites in total.