Scientists Get Closer To Redefining The Length Of A Second : NPR

Summary (IA Generated)

Scientists have made new more accurate comparisons between types of atomic clocks.

toggle caption Jun Ye Scientists have made new more accurate comparisons between types of atomic clocks.

‘Every time you want to find your location on the planet, you’re asking what time it is from an atomic clock that sits in the satellite that is our GPS system,’ Colin Kennedy, a physicist at the Boulder Atomic Clock Optical Network (BACON) Collaboration, tells NPR’s All Things Considered.

The worldwide standard atomic clocks have for decades been based on cesium atoms — which tick about 9 billion times per second.

But newer atomic clocks based on other elements tick much faster — meaning it’s possible to divide a second into tinier and tinier slices.

That means having a clock that if set back billions of years to the beginning of the universe would only be off by a second, adds physicist Jun Ye, who was also involved in the collaboration.

As the scientists with BACON, which includes researchers from the University of Colorado Boulder and the National Institute of Standards and Technology, wrote in the science journal Nature last week, they compared three next-generation atomic clocks that use different elements: aluminum, strontium and ytterbium.

What resulted is a more accurate comparison of these types of atomic clocks than ever before.