VANGUARD 3

VANGUARD 3 is an active satellite operated by GSFC (United States), launched on 1959-09-18 from Cape Canaveral Space Force Station, United States. After more than 67 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 509 km and 3,201 km with an inclination of 33.3°. It travels at approximately 25,060 km/h (6.96 km/s), completing one full orbit every 2 hours 4 minutes — that’s roughly 11.62 orbits per day. Its orbital eccentricity of 0.1636 gives it a noticeably elliptical path, with significant altitude variation between perigee and apogee. At its current altitude, the estimated orbital lifetime before atmospheric re-entry is thousands of years. Orbital Radar tracks VANGUARD 3 in real time using the latest two-line element set (TLE) data, providing live position, altitude, speed and orbital path updated continuously.

VANGUARD 3 orbits at an average altitude of 1,855 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 VANGUARD 3’s average altitude, there are currently 6 active payloads and 27 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 33.3°, VANGUARD 3 passes over latitudes between 33.3°N and 33.3°S, covering the tropical and temperate zones where most of the world’s population resides. Low-to-mid inclination orbits are efficient to reach from equatorial and mid-latitude launch sites. United States operates approximately 13,279 active satellites in total.