Track NAVSTAR 21 (USA 64) Satellite in Real Time
Detailed information about NAVSTAR 21 (USA 64) satellite
Designator id: 1990-088A
Description of NAVSTAR 21 (USA 64) Satellite:
Global Positioning System (GPS) was developed by the US Department of Defense to provide all-weather round-the-clock navigation capabilities for military ground, sea, and air forces. Since its implementation, GPS has also become an integral asset in numerous civilian applications and industries around the globe, including recreational used (e.g., boating, aircraft, hiking), corporate vehicle fleet tracking, and surveying. GPS employs 24 spacecraft in 20,200 km circular orbits inclined at 55 degrees. These vehicles are placed in 6 orbit planes with four operational satellites in each plane.
GPS Block 2 was the operational system, following the demonstration system comprised of Block 1 (Navstar 1 - 11) spacecraft. These spacecraft were 3-axis stabilized, nadir pointing using reaction wheels. Dual solar arrays supplied 710 watts of power. They used S-band (SGLS) communications for control and telemetry and UHF cross-link between spacecraft. The payload consisted of two L-band navigation signals at 1575.42 MHz (L1) and 1227.60 MHz (L2). Each spacecraft carried 2 rubidium and 2 cesium clocks and nuclear detonation detection sensors. Built by Rockwell Space Systems for the US Air Force, the spacecraft measured 5.3 m across with solar panels deployed and had a design life of 7.5 years.
1 20830U 90088A 12338.87932792 .00000079 00000-0 10000-3 0 5538 2 20830 053.9673 182.1289 0016850 182.6809 177.3776 01.87754543160057