Even when you're out of range of the atomic master clocks

Space Time Sam Kaplan

Even watches that sync with an atomic clock aren’t accurate everywhere. They contain a radio that picks up a signal from a long-range tower connected to atomic clocks around the world. But the towers have a range of only about 1,500 miles, leaving large regions, including South America and Canada, uncovered. The Seiko Astron is the first watch that uses GPS, so it can automatically set the time anywhere.

Seiko engineers connected the Astron’s quartz movement to a custom circuit board that contains a processor and GPS radio. The team programmed the processor with a world map broken into one million square quadrants, each associated with one of 39 time zones. Once a day, the GPS radio turns on and connects with four or more satellites orbiting the globe to pinpoint its location; the processor then determines which time zone it’s in and sets the date and time accordingly. (Users can also force the watch to reset by pressing a button on the side.) The Astron takes 30 seconds to sync, whereas atomic watches can take up to two minutes. And, because the lithium-ion-powered watch’s 1.5-inch face is made from a matrix of seven solar cells, travelers will never be caught with either the incorrect time or a stopped watch.

SEIKO ASTRON

Face Size 1.5 inches
Weight 4.8 ounces
Price From $2,300

Click the video for a 360-degree look.

5 Comments

Oh sweetness. To think I've been making do with a Citizen World Perpetual A-T... tsk tsk...

Neat! I know what I like for Christmas!

so wait, let me get this straight; we want to wear a time piece that syncs up with the GPS grid, which has been proven to be easily hackable, after a TED talk that basically explained that the resolution of GPS devices are going to leap within the next year from 6 feet of accuracy to 6 inches.

i have enough problems with being easily contacted with the walmart phone that i "sometimes" lose, on purpose. the last thing i need is for them to be able to find me at any minute...

to mars or bust!

@ ghost

GPS is a time signal. This watch doesn't give your position. It only receives the GPS time signal to set its time. So if anyone "hacks" GPS, you'll have the wrong time on your watch. Plus, it only receives, it doesn't send, so nobody can track you.

There is a problem using GPS for time keeping. The consortium which manages GPS had decided recently not to insert any more leap seconds (see http://en.wikipedia.org/wiki/Leap_second), which means this watch is soon going to be off by a few seconds -- and the error would grow by a second every 2-3 years!

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