Earth spins faster: August 5 will be one of the shortest days in recorded history

On Tuesday, August 5, the day on Earth will be shorter than the usual 24 hours by only 1.25 milliseconds, making it one of the shortest on record since scientific observations began. This is part of a mysterious phenomenon that puzzles scientists: after a long slowdown, the Earth began to rotate faster, and the reasons for this acceleration are still not definitively established. This is reported by UNN with reference to Space.

Details

According to Timeanddate.com, on Tuesday, "August 5, the solar day on Earth will be slightly shorter than the usual 24 hours, making it not only one of the shortest days of 2025, but also since observations began."

The difference, as indicated, will be 1.25 milliseconds, and although this is almost imperceptible to humans, technically this day will be one of the shortest in 2025, as well as one of the shortest in the entire period of scientific observations.

Addition

This phenomenon is part of a mysterious trend: after a long period of slowing down, the Earth has begun to rotate faster in recent years, and scientists still have no clear explanation for this. To understand this, it is worth distinguishing between two concepts: sidereal and solar day. A sidereal day is the time it takes for the Earth to make a full 360-degree rotation relative to the stars (about 23 hours 56 minutes). It explains why stars and planets rise earlier every day. But the familiar 24-hour day is a solar day, measured from noon to noon, oriented to the Sun, and lasts 86,400 seconds.

In general, since the beginning of accurate timekeeping in 1973, days have become longer mainly due to the influence of the Moon. Its gravity creates tidal friction, which gradually slows down the Earth's rotation. But the Moon's position, particularly its declination to the equator, can temporarily accelerate or slow down the planet's rotation.

As for the latest acceleration, the reasons remain unclear. Among the hypotheses are the influence of global warming or changes in the movement of the Earth's liquid core. This process can cause the outer layers of the planet to rotate slightly faster.

Although such changes are not noticeable to people in everyday life, if the trend continues, by 2029, a so-called "negative leap second" may be introduced into the international time system for the first time, meaning the day will be shortened by one second.

Earlier, UNN wrote that on July 22, the Earth will rotate 1.34 milliseconds faster, making that day the second shortest in the history of observations. This is part of a mysterious trend of accelerating the planet's rotation, which could lead to the subtraction of a second from atomic clocks in 2029.