Which atomic clocks are best? The first time zone, Greenwich Mean Time, was established in the late 1600s to assist sailors before the invention of the train and railway in the mid-1800s expanded the ...

Gear-obsessed editors choose every product we review. We may earn commission if you buy from a link. Why Trust Us? Researchers recently announced a big step forward in the development of a nuclear ...

The heart of a minuscule atomic clock—believed to be 100 times smaller than any other atomic clock—has been demonstrated by scientists at the Commerce Department’s National Institute of Standards and ...