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OSA | Living History

A strontium-ion optical clock, National Physical Laboratory, UK.


Optical Clock

Atomic clocks based on the elements strontium and ytterbium may prove even more precise than cesium clocks, considered the most accurate time-keepers.

Precise time is especially important for GPS, radio astronomy, financial transactions and identifying changes in fundamental constants. (Photo: National Physical Laboratory)

(Courtesy of National Physical Laboratory)