In the U.S., a new atomic clock called NIST-F4 has already proven to be one of the most precise timekeepers yet.

The laser light used in a nuclear clock is also much higher in frequency than that required for atomic clocks. This leads to more 'ticks' per second and therefore more precise timekeeping.

So, if you own a grandfather clock, wall clock or have a digital or analog clock on your nightstand without that technology, you’ll have to remember to adjust it on March 9.

If an atomic clock fell out of sync with a nuclear clock, for example, some change in the underlying physics might be responsible. Only time will tell. Curious about the world?