Navstar 47

Description

Navstar 47 (USA 150) was the latest addition to the American GPS fleet of navigation satellites, and was launched by a Delta 2 rocket from Cape Canaveral at 01:48 UT. The 24-spacecraft fleet was completed in 1994, but Navstar 47 replaced a failing member. GPS navigational location had until recently been at 100 meter accuracy for civilian use signals, and at 20 meter accuracy for military use signals. As of 1 May 2000, the DoD had voided the intentional degradation of the accuracy for civilian use, and made it on a par with the military accuracy. But it retained the prerogative to degrade the accuracy at selected locations when necessary. Also known as PRN20 (in GPS parlance), it replaced the failing PRN14 in Slot E-1. An update of the GPS fleet has been provided by Richard B. Langley, and is appended in section C-2.