I recently read an article that said for the last fifty years Earth’s rotation has been gradually slowing forcing international timekeepers to add a “leap second” every now and then in order to keep their atomic clocks accurate. But now, rather suddenly, it seems the planet has started spinning much faster. So much so that these same timekeepers are considering adding a first-ever negative leap second, a “drop second”.
That might not seem like a lot, but it has big consequences over time because atomic clocks—which are used in GPS satellites—don’t take into account the Earth’s changing rotation. If Earth spins faster then it gets to the same position a little earlier. A half-a-millisecond equates to 10-inches or 26 centimeters at the equator.
Check out, Do We Need A ‘Drop Second?’ The Worrying Reason Why Earth May Be Speeding Up After Decades Of Slowing Down. But don’t delay, apparently the days are getting shorter.