Earth rotates once in about 24 hours with respect to the Sun, but once every 23 hours, 56 minutes and 4 seconds with respect to other distant stars. Scientists call this difference crucial to ...

Forbes contributors publish independent expert analyses and insights. An award-winning reporter writing about stargazing and the night sky. Earth could be about to record its fastest-ever rotation.

A strange shift in Earth's rotation is making our days milliseconds shorter — and scientists are racing to understand why. When you purchase through links on our site, we may earn an affiliate ...

Earth takes 24 hours to complete a full rotation in a standard day, equal to exactly 86,400 seconds. July 9 was the first of three days in which a millisecond or more could be shaved off the clock on ...