Though we sum up a day as 24 hours and a year as 365 days, Earth's rotational and orbital speeds aren't exactly consistent. Instead, both fluctuate, swayed by atmospheric drag, tidal forces, changes ...

Aren’t the summer days supposed to be longer and the winter days shorter? Since when have things gone in reverse for the summertime? Since now, maybe? Starting today? Okay, here’s what’s going on.

Scientists announced Monday that Earth is rotating slightly faster than normal, resulting in what is expected to become the second-shortest day ever recorded since precise atomic timekeeping began.

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 ...