EXPLORER 30

EXPLORER 30 is an active satellite operated by NRL (United States), launched on 1965-11-19 from Wallops Flight Facility / MARS, United States on the Solar Explorer A launch. After more than 61 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 657 km and 848 km with an inclination of 59.7°. It travels at approximately 26,929 km/h (7.48 km/s), completing one full orbit every 100 minutes — that’s roughly 14.42 orbits per day. At its current altitude, the estimated orbital lifetime before atmospheric re-entry is ~25–100 years. Orbital Radar tracks EXPLORER 30 in real time using the latest two-line element set (TLE) data, providing live position, altitude, speed and orbital path updated continuously.

EXPLORER 30 orbits at an average altitude of 753 km in the mid-LEO band, where atmospheric drag is minimal but radiation exposure remains manageable. Objects at this altitude persist for decades to centuries, making debris mitigation critical. This regime is popular for remote sensing constellations and scientific instruments that need stable, long-duration orbits. Within ±50 km of EXPLORER 30’s average altitude, there are currently 404 active payloads and 2,158 tracked debris or rocket body fragments. With an inclination of 59.7°, EXPLORER 30 passes over latitudes between 59.7°N and 59.7°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 13,279 active satellites in total, of which 177 share a similar altitude band with EXPLORER 30.