SOLRAD 3/INJUN 1

SOLRAD 3/INJUN 1 is an active satellite operated by ONR / SUI (United States), launched on 1961-06-29 from Cape Canaveral Space Force Station, United States. After more than 65 years in orbit, it is one of the longest-surviving objects in the space catalogue. It orbits in Low Earth Orbit (LEO) at altitudes between 869 km and 987 km with an inclination of 66.8°. It travels at approximately 26,604 km/h (7.39 km/s), completing one full orbit every 104 minutes — that’s roughly 13.90 orbits per day. At its current altitude, the estimated orbital lifetime before atmospheric re-entry is ~100–500 years. Orbital Radar tracks SOLRAD 3/INJUN 1 in real time using the latest two-line element set (TLE) data, providing live position, altitude, speed and orbital path updated continuously.

SOLRAD 3/INJUN 1 orbits at an average altitude of 928 km in the upper LEO band, where atmospheric drag is negligible and objects can persist for centuries to millennia. This altitude is used by broadband constellations like OneWeb and by scientific missions requiring stable orbits far from the densest debris bands. Within ±50 km of SOLRAD 3/INJUN 1’s average altitude, there are currently 369 active payloads and 1,403 tracked debris or rocket body fragments. With an inclination of 66.8°, SOLRAD 3/INJUN 1 passes over latitudes between 66.8°N and 66.8°S, covering most populated land masses in both hemispheres. This mid-inclination band balances global coverage with efficient launch energy requirements. United States operates approximately 13,276 active satellites in total, of which 166 share a similar altitude band with SOLRAD 3/INJUN 1.