USA 142

USA 142 is an active satellite operated by USAF SMC (United States), launched on 1999-04-09 from Cape Canaveral Space Force Station, United States on the DSP 19? launch. With over 27 years in orbit, it has far exceeded many satellites’ design lifetimes. It orbits in Medium Earth Orbit (MEO) at altitudes between 588 km and 34,717 km with an inclination of 29.4°. It travels at approximately 14,664 km/h (4.07 km/s), completing one full orbit every 10 hours 18 minutes — that’s roughly 2.33 orbits per day. Its orbital eccentricity of 0.7103 gives it a noticeably elliptical path, with significant altitude variation between perigee and apogee. Orbital Radar tracks USA 142 in real time using the latest two-line element set (TLE) data, providing live position, altitude, speed and orbital path updated continuously.

USA 142 orbits at an average altitude of 17,653 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 USA 142’s average altitude, there are currently 1 active payload and 10 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 29.4°, USA 142 passes over latitudes between 29.4°N and 29.4°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 13,204 active satellites in total.