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NAVSTAR 43 (USA 132)

GPS Navigation Satellite (Block IIR) · US Space Force

Navstar 43 (USA 132) belongs to the generation of GPS satellites that quietly ended a decades-old form of government-imposed inaccuracy. Until May 2000, every civilian GPS receiver on Earth — including this satellite's own signal — was deliberately degraded by a Pentagon program called Selective Availability, blurring positioning accuracy from meters to nearly a football field on purpose, specifically so an adversary couldn't use civilian GPS to guide a weapon. President Clinton ordered SA switched off entirely, and overnight, every hiking GPS unit and car navigation system on the planet got ten times more accurate for free. Launched in 1997, this Block IIR satellite carries the redesigned atomic clocks and autonomous navigation capability that let the GPS constellation keep functioning accurately for up to six months even if it completely lost contact with ground control.