MIDAS 4

MIDAS 4 is an active satellite operated by USAF SSD (United States), launched on 1961-10-21 from Vandenberg Space Force Base, United States. After more than 65 years in orbit, it is one of the longest-surviving objects in the space catalogue. It orbits in Medium Earth Orbit (MEO) at altitudes between 3,491 km and 3,759 km with an inclination of 95.9°. It travels at approximately 22,733 km/h (6.31 km/s), completing one full orbit every 2 hours 46 minutes — that’s roughly 8.68 orbits per day. Orbital Radar tracks MIDAS 4 in real time using the latest two-line element set (TLE) data, providing live position, altitude, speed and orbital path updated continuously.

MIDAS 4 orbits at an average altitude of 3,625 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 MIDAS 4’s average altitude, there are currently 5 active payloads and 24 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 95.9°, MIDAS 4 passes over latitudes between 95.9°N and 95.9°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 13,279 active satellites in total, of which 5 share a similar altitude band with MIDAS 4.