Scientists break down the reasons why days are getting shorter—and the mystery they're still trying to solve about Earth's ...

Figuring out the day length of Earth is more complicated than you might imagine. While on average a day is 24 hours long, throughout the year the planet's rotation can speed up and slow down, with ...

July 22 is one of the shortest days in history due to Earth spinning faster. The shortest day in history is coming up next month.

Until 2020, the shortest day ever recorded by atomic clocks was 1.05 milliseconds under the standard length. Since then, Earth has broken that record every year by roughly half a millisecond.