The Earth just experienced a record-breaking day of rotation.

(Dan Tri) - July 22 became the second shortest day ever recorded in modern history, the Earth experienced a remarkable phenomenon when it completed a rotation around its axis faster than usual.

Second shortest day in history

Earth is experiencing one of its shortest days ever and there will be many more days to come (Photo: Canva).

According to data from precise timekeeping systems, our planet ends its day about 1.34 milliseconds earlier than the standard 24-hour mark, a tiny deviation that humans cannot perceive, but has great significance in scientific research on Earth dynamics.

Since ancient times, scientists have determined that the Earth's rotation has slowed down over time due to tidal friction from the Moon, causing the Moon to gradually move away from the planet and lengthen the days on Earth. According to a 2023 study, billions of years ago, a day was only about 19 hours long.

However, something unexpected happened: the Earth began to spin faster, and rotation records were continuously broken.

Previously, the record for fastest rotation was held on July 10, with a time 1.36 milliseconds shorter.

There's no official confirmation from IERS or TimeAndDate, but on July 22, Earth's rotation will shorten by about 1.34 milliseconds, which will certainly put it in the second-shortest spot of the year, surpassing the upcoming August 5 (which is forecast to be just 1.25 milliseconds shorter).

Reversing a Million-Year Trend

Scientists have not been able to explain the rapid rotation of the Earth (Photo: Getty).

This unusual acceleration has scientists baffled. Atmospheric and ocean models cannot fully explain the current unusual short-term fluctuations.

Several studies, including the 2024 report, suggest that polar ice melt and rising sea levels could change the distribution of mass on Earth's surface, thereby affecting rotational angular momentum.

However, instead of making the Earth spin faster, this factor appears to contribute to slowing down the rotation.

One theory gaining traction is a change in the motion of Earth's liquid core. If the core slowed down, the mantle and outer crust might spin faster to conserve angular momentum, leading to the shortening of the day we're seeing.

According to Professor Leonid Zotov from Moscow State University, one of the leading experts on the Earth's rotation, the real cause of this acceleration remains unclear.

He predicts that the acceleration is only temporary, and that Earth will likely slow down again in the coming years, continuing a long-term trend that dates back millions of years.

While the shortening hasn’t yet affected everyday life, it could lead to significant changes in the near future. If the trend continues, scientists could be forced to subtract a second from atomic clocks (called a “negative leap second”) around 2029.

This is unprecedented and could have profound implications for GPS, communications, finance and aviation systems, which rely on absolute precision in timing.

Source: https://dantri.com.vn/khoa-hoc/trai-dat-vua-trai-qua-ngay-quay-nhanh-ky-luc-20250722084858440.htm