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home | newest check | boards | help index | log | ps | userlogin | send sysop | slog | status forward | bcm news | users | version | remove cookieKF5JRV > TODAY 22.02.26 23:17l 10 Lines 1097 Bytes #7 (0) @ WW BID : 8580_KD5TCY Subj: Today in History - Feb 22 Path: JH4XSY<N3HYM<W9GM<VE3CGR<KD5TCY Sent: 260222/1137Z 8580@KD5TCY.#NWAR.AR.USA.NA BPQ6.0.24 The U.S. Air Force launches Navstar 1, the world窶冱 first operational GPS satellite, from Vandenberg Air Force Base in California. GPS begins as a military technology, but expands to transform industries from aviation to communications. Global Positioning System (GPS) technology is an indispensible part of 21st century life, powering everything from rideshare apps to fitness trackers to commercial aviation. The origins of GPS technology, however, lie in the early years of the Cold War space race. When the USSR launched its first satellite, Sputnik, into orbit in 1957, American scientists observed the Doppler effect: Sputnik's radio signal frequency increased as it moved closer, and decreased as it moved farther away. These changes in radio signal frequency allowed scientists to track Sputnik's movement across the sky. Inspired by this observation, DARPA (Defense Advanced Research Projects Agency) launched the Transit program, which provided navigation largely to warships, submarines, freighters and private maritime users. The first Transit satellite entered orbit in 1960.
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