VANGUARD 1

VANGUARD 1 is an active satellite operated by NRL (United States), launched on 1958-03-17 from Cape Canaveral Space Force Station, United States. After more than 68 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 651 km and 3,819 km with an inclination of 34.3°. It travels at approximately 24,500 km/h (6.81 km/s), completing one full orbit every 2 hours 13 minutes — that’s roughly 10.86 orbits per day. Its orbital eccentricity of 0.1841 gives it a noticeably elliptical path, with significant altitude variation between perigee and apogee. Orbital Radar tracks VANGUARD 1 in real time using the latest two-line element set (TLE) data, providing live position, altitude, speed and orbital path updated continuously.

VANGUARD 1 orbits at an average altitude of 2,235 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 1’s average altitude, there are currently 1 active payload and 16 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 34.3°, VANGUARD 1 passes over latitudes between 34.3°N and 34.3°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 13,275 active satellites in total.