
Scientists say Earth might spin a little faster this July and August, which means the days could be slightly shorter than usual. According to Timeanddate.com, July 9, July 22, and August 5 are expected to be the shortest days this year.
But don’t worry — the change is very tiny. For example, August 5 might be just 1.51 milliseconds shorter than a normal day. That’s way too small for people to notice.

Has Earth Always Spun at the Same Speed?
No. Long ago, Earth used to take more or fewer days to go around the Sun. Scientists believe that, in the past, a year could have had 490 to 372 days, instead of the 365 days we have now.
Why is Earth Spinning Faster Now?
There are a few reasons why Earth might be spinning faster:
- The Earth’s core could be affecting the speed.
- Melting glaciers are moving water around, changing Earth’s mass.
- Weather patterns like El Niño and La Niña can also play a role.
- Even the Moon might be affecting Earth’s spin. On the three dates mentioned, the Moon will be far from Earth’s equator, which could matter.
What Do Experts Say?
Scientists are surprised by this faster rotation.
Judah Levine, a physicist at the U.S. National Institute of Standards and Technology, said in 2021 that we used to add leap seconds to keep our clocks in sync with Earth. But now, we might have to remove a leap second in 2029, which has never happened before.
Leonid Zotov, a scientist from Moscow State University, said, “Nobody expected this.” He believes something deep inside Earth is causing the change because current ocean and air models don’t explain it.
Some days in July and August 2025 might be slightly shorter because Earth is spinning a bit faster — and scientists are still trying to figure out why.