The rotation of the earth accelerates randomly, and no one really knows why. These accelerations, observed several times in recent years, have had no impact on daily life, but they have not escaped the scientific community. Tuesday, August 5, the rotation of the earth should again accelerate, shortening the day from 1.25 to 1.51 milliseconde.
According to the Time and Date site, this current forecast is established by the International Earth Rotation and Reference Systems Service and the United States Naval Observatory. The initial forecast, which tapped on 1.51 millisecond, was revised at 1.25 millisecond. It will also be the third daily acceleration of the Earth this summer, after those of July 10 and July 22.
If the first estimate was confirmed, on August 5, 2025 would become the third shortest day ever recorded, behind June 30, 2022, when the earth had turned 1.59 millisecond faster, and on July 5, 2024, where it had completed its 1.66 millisecond rotation faster. If the forecast is wrong, this day could even delight first place.
For the record, the earth generally puts around 86,400 seconds to perform a complete rotation. A millisecond is equivalent to 0.001 seconds. This remains imperceptible for humans and without concrete consequences.
What makes the earth run faster?
There are many possible reasons for accelerating terrestrial rotation. The most commonly advanced explanation is linked to the current position of the moon compared to the earth. When the moon is further north or south of the equator, this can influence the speed of rotation of our planet.
On August 5, 2025, the moon will be much further south of the equator, which would explain this slight acceleration. This effect should have a temporary impact on the terrestrial orbit.
Science cannot explain everything
Scientists remain intrigued by the very fact that the land accelerates. About 245 million years ago, at the time of the dinosaurs, the days were shorter of an hour and a half compared to today. Since then, terrestrial rotation has slowed, mainly because of the influence of the moon on the oceans. The official measures, started in 1973, confirm this gradual slowdown.
However, a recent trend shows that the earth accelerates, and if this increase in speed is partly explained by the lunar orbit, it is not fully understood. A study published in 2023 in the journal Nature argues that the terrestrial nucleus would have started to slow around 2010, which could explain the acceleration of rotation. But this hypothesis remains to be confirmed.
