2 days ago
Earth spinning faster makes today one of the shortest on record
If you are counting down to something exciting, then you might be happy to hear this Tuesday 22 July 2025, will be one of the shortest days on record, as Earth will complete its full rotation in slightly less time than usual. But, don't get too excited, you probably won't notice the difference, as the day will be just 1.34 milliseconds less than the standard 24 what's going on? Read on to find more.
Normally, we think of the Earth taking 24 hours, or 86,400 seconds to rotate fully on its axis in a day. However, this isn't an exact figure, as the speed of Earth's rotation depends on many factors, including the positions of the Sun and the Moon, and Earth's gravitational have found that on average the Earth has been slowing down by about two milliseconds per means that 250 million years ago - when dinosaurs roamed the Earth - a day was shorter, at around 23 hours long.
A big factor in the slowing down of the rotation over many centuries is due to the pull of the Moon. The Moon affects our planet's spin through something known as tidal braking. This is when the gravitational pull from the Moon causes our planet to bulge (expand) in places, and this slows the momentum of the Earth's this case the Moon acts almost like a handbrake slowing down the Earth's spin.
The International Earth Rotation and Reference Systems Service (IERS) is constantly measuring the length of our days to a high level of use atomic clocks to monitor Earth's rotation with millisecond precision, and have been keeping records since 2020, Earth has repeatedly broken its own speed shortest day ever measured occurred on 5 July 2024, when Earth's rotation was completed 1.66 milliseconds faster than to the IERS, earlier this month, 9 July, was the shortest day recorded this year, clocking in at 1.36 milliseconds less than 24 today - 22 July - Earth is expected to complete its spin 1.34 milliseconds early, making it a close runner-up.
