Do you know that widespread feeling that there’s never enough time in a day to solve all the problems that await us?
Well, you should know that this Wednesday, July 9, that idea could become partially true.
This is because there is a high probability that this will be one of the shortest days in the history of our planet.
Although no scientist knows exactly what is behind this phenomenon, recent studies reveal that the rotation of the Earth – the movement it makes on its own axis – seems to have accelerated in the last five years.
But don’t worry: the change is so subtle that no adjustment is needed to the clock hands, although some more sensitive equipment (such as satellites or GPS) may require technical adjustments.
Accelerated rotation
The warning was issued by astrophysicist Graham Jones, of the website timeanddate.com, who makes precise measurements of the weather with advanced tools.
In a publication, the expert explains that the full rotation of the Earth lasts exactly 86,400 seconds, the equivalent of 24 hours.
Since 2020, however, the planet seems to be in a hurry.
During the summer in the northern hemisphere and winter in the southern hemisphere, the Earth completed its rotation a few thousandths faster than expected.
To put this in perspective, a millisecond is very small, equivalent to 0.001 seconds. A blink takes 100 milliseconds. And the flapping of a bee’s wings lasts about 5 milliseconds.
But let’s go back to the current theme: according to Graham, by 2020, the shortest day ever recorded by atomic clocks, which measure time with great precision, was -1.05 milliseconds.
In practice, this means that the full rotation on its axis was completed moments before the clock marked the 86,400 seconds.
This has become increasingly common, with such day shortenings occurring almost every year in recent times.
Records include -1.66 milliseconds on July 5, 2024, -1.47 on July 9, 2021, -1.59 on June 30, 2022 and -1.31 on June 16, 2023.
Experts project that this “waste of time” will probably be repeated in 2025.
According to Jones, this could happen on three specific dates in the coming weeks: this July 9, July 22 and August 5.
These days, the Moon is further away from the equator and wields less gravitational influence.
And the prediction is that the rotation will be completed between -1.30 to -1.51 milliseconds on these stipulated dates.
Why is this happening?
How do you explain this “acceleration” of Earth? Scientists are not yet entirely sure.
An article written by Jones cites some possible explanations.
“Long-term variations in Earth’s rotation speed can be affected by a variety of factors, such as the complex movements of the planet’s nucleus, oceans and atmosphere,” he writes.
The fact that we have only had atomic clocks capable of making more accurate measurements since the 1950s also makes it difficult to understand this long-term dynamic.
In the same article, researcher Leonid Zotov, considered a world authority in Earth’s rotation movements, admits that no one expected such a phenomenon.
“Most scientists believe this has something to do with the inside of the planet. Oceanographic and atmospheric models are not enough to explain this massive acceleration,” says the expert, who works at Moscow State University, Russia.
Zotov projects that the trend for the coming years will be the reversal of the phenomenon. As a result, the planet we inhabit will enter a phase of deceleration.
In an interview with BBC Radio 4’s programme in the UK, Professor Hannah Fry said: “Throughout the story, we have always defined our time according to the speed of rotation of the Earth.”
“But our planet is not very good at measuring time. After all, we live on a somewhat irregular rock that floats in space,”joked the Professor of Public Understanding of Mathematics at Cambridge University (United Kingdom).
Fry emphasises that rotation is not a constant movement and has experienced significant variations throughout the geological ages.
“The planet used to spin much faster in the past. We can check it by analysing ancient corals and counting their inner rings, similar to how we do with trees,” he explains.
“About 430 million years ago, a year lasted 420 days,” he explains. “In other words, there were many more nights between each birthday.”