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Now We Know Where We Stand, and It's About Time

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America has seen its last Lost Generation.

Thanks to an invisible armada of incessantly broadcasting satellites, collectively called the Global Positioning System, and to the explosive proliferation of GPS receivers in gadgets from dashboard map units to cellphones to dog collars, even the cartographically clueless are now good to go.

The same technology that allows the military to drop precision-targeted bombs on terrorists has become a $30 billion worldwide market, spawning devices that lead hikers through the trackless wild, recover itinerant tykes with GPS units sewn into their backpacks, let golfers see the distance to the next hole, stamp the location on digital photos and show the nearest pizza joint on a PDA screen. Very soon it may be possible to find your lost keys as receivers shrink to the size of a dime and smaller.

It has all happened deliriously fast. Modern GPS has been fully operational only since 1995. Today it consists of 30 one-ton satellites, each the size of a pickup truck, orbiting the Earth about 12,000 miles high. At least 24 have to be working at any given time; that way, almost everywhere you go on the planet, six of them are above the horizon.

The U.S. Air Force runs the whole show. But it has been a dual-use system since 1983, when the Soviet Union downed a Korean Air Lines passenger jet that strayed into Soviet airspace because of navigational error, prompting President Ronald Reagan to open GPS to civilian and commercial users. For the next 17 years, nonmilitary users got a deliberately degraded signal until President Bill Clinton ended the practice, instantly improving precision fivefold.

Happily, however, these innovations are arriving just in time for America's impending Geezer Boom, in which a growing number of senior citizens spend a growing fraction of their lives looking for misplaced items -- or, indeed, misplaced geezers themselves. As our demographics get grayer, GPS will be there to help, confirming the noted philosopher who succinctly said it all: "No matter where you go . . . there you are."

From The Washington Post
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