This summer has seen the shortest days in Earth’s recorded history Scientists break down the reasons why days are getting shorter—and the mystery they're still trying to solve about Earth's core.

(NEW YORK) -- Tuesday, July 22 will be the second-shortest day of the year, as Earth completes a full rotation in less time than usual. The planet on Tuesday will experience a shorter rotation ...

Earth doesn't rotate exactly on schedule. Scientists believe that today is going to be about a millisecond short of a typical 24-hour day.

Earth doesn't rotate exactly on schedule. Scientists believe that today is going to be about a millisecond short of a typical 24-hour day.