New US Atomic Clock Goes Live

PaisteUser (810863) writes with news about a new, hyper-accurate atomic clock unveiled by the National Institute of Standards and Technology. "A new atomic clock, so accurate it will lose or gain only one second every 300 million years, was unveiled Thursday by the National Institute of Standards and Technology, a branch of the U.S. Department of Commerce. The NIST-F2 had been in development for about a decade and is three times more accurate than the F1, which has been in use since 1999. The institute will continue operating both clocks for now at its campus in Boulder, Colorado."

Re:How, exactly, do we know?

[schneidafunk]

Even if it is arbitrary, we can use it for synchronization as long as every relies on it as the standard.

FTA:
  "If we've learned anything in the last 60 years of building atomic clocks, we've learned that every time we build a better clock, somebody comes up with a use for it that you couldn't have foreseen," says physicist Steven Jefferts, lead designer of NIST-F2.

Re:Ah another seemingly benign NIST approved stand

[Anonymous Coward]

Atomic clocks in the 70s could show dilation effects from travel on airplanes or in satellites. GPS satellites regularly have to deal with this. The most precise clocks these days (more precise than the ones in the story here) can measure time dilation effects from just stacking the clocks on top of each other due to change in altitude of less than a meter. But for the most part these effects don't matter in the big picture, as you can define time relative to a frame not moving with respect to Earth at a specific elevation.