CRRES

CRRES is an active satellite operated by USAF SSD / NASA MSFC (United States), launched on 1990-07-25 from Cape Canaveral Space Force Station, United States on the CRRES launch. With over 36 years in orbit, it has far exceeded many satellites’ design lifetimes. It orbits in Medium Earth Orbit (MEO) at altitudes between 307 km and 32,773 km with an inclination of 17.7°. It travels at approximately 15,016 km/h (4.17 km/s), completing one full orbit every 9 hours 35 minutes — that’s roughly 2.50 orbits per day. Its orbital eccentricity of 0.7085 gives it a noticeably elliptical path, with significant altitude variation between perigee and apogee. Orbital Radar tracks CRRES in real time using the latest two-line element set (TLE) data, providing live position, altitude, speed and orbital path updated continuously.

CRRES orbits at an average altitude of 16,540 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 CRRES’s average altitude, there are currently 1 active payload and 15 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 17.7°, CRRES passes over latitudes between 17.7°N and 17.7°S, concentrating coverage over equatorial and near-equatorial regions. Low-inclination orbits maximise revisit rates over specific tropical zones. United States operates approximately 13,342 active satellites in total.