HST

HST is an active satellite operated by United States, launched on 1990-04-24 from Cape Canaveral, Florida. With over 36 years in orbit, it has far exceeded many satellites’ design lifetimes. It orbits in Low Earth Orbit (LEO) at altitudes between 476 km and 478 km with an inclination of 28.5°. It travels at approximately 27,466 km/h (7.63 km/s), completing one full orbit every 94 minutes — that’s roughly 15.30 orbits per day. Its near-circular orbit (eccentricity close to zero) means it maintains a very consistent altitude throughout each revolution. It is part of the Tdrss constellation group. At its current altitude, the estimated orbital lifetime before atmospheric re-entry is ~1–3 years. Orbital Radar tracks HST in real time using the latest two-line element set (TLE) data, providing live position, altitude, speed and orbital path updated continuously.

HST orbits in the most densely populated region of Low Earth Orbit, between roughly 300 and 600 km altitude. This band is home to the International Space Station, most Earth observation satellites, and the bulk of the Starlink constellation. Objects here experience measurable atmospheric drag, which gradually lowers their orbit over months to years and eventually causes re-entry. The relatively short signal path makes this altitude ideal for low-latency communications and high-resolution imaging.