THEMIS E

THEMIS E is an active satellite operated by National Aeronautics and Space Administration (NASA)/University of California, Berkeley (in partnership with Germany, France, Austria, Canada) (United States), launched on 2007-02-17 from Cape Canaveral, Florida. After 19 years in orbit, it continues to be tracked by global surveillance networks. It orbits in Highly Elliptical Orbit (HEO) at altitudes between 795 km and 78,417 km with an inclination of 6.4°. It travels at approximately 10,600 km/h (2.94 km/s), completing one full orbit every 27.3 hours — that’s roughly 0.88 orbits per day. Its orbital eccentricity of 0.8441 gives it a noticeably elliptical path, with significant altitude variation between perigee and apogee. At geostationary altitude, there is no meaningful atmospheric drag — this object will remain in orbit indefinitely unless actively deorbited. Orbital Radar tracks THEMIS E in real time using the latest two-line element set (TLE) data, providing live position, altitude, speed and orbital path updated continuously.

THEMIS E follows a Highly Elliptical Orbit, sweeping between 795 km (perigee) and 78,417 km (apogee). It spends most of its 27.3 hours orbital period near apogee, effectively loitering over a region of interest before rapidly sweeping through perigee — a profile used for high-latitude communications (Molniya orbits), early-warning systems and magnetospheric science. With an inclination of 6.4°, THEMIS E passes over latitudes between 6.4°N and 6.4°S, concentrating coverage over equatorial and near-equatorial regions. Low-inclination orbits maximise revisit rates over specific tropical zones. United States operates approximately 12,360 active satellites in total.