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23rd July 2025
01:41pm BST
Scientists have discovered that the Moon is slowly drifting away from Earth, meaning that days are getting longer.
Contrary to long-held assumptions that our only natural satellite remains same distance from Earth, experts now believe the Moon has been slowly moving away from us for millions of years.
This has had the effect of slowing how the speed at which the Earth spins, and therefore causing the planet to take longer for it to complete a full day's rotation.
In a study published by a team at the University of Wisconsin-Madison, researchers used rock sediments from a 90-million-year-old rock formation to analyse the Earth's relationship to the moon 1.4 billion years ago.
They concluded that back then, a day on Earth lasted just over 18 hours because the Moon was much closer.
"As the moon moves away, the Earth is like a spinning figure skater who slows down as they stretch their arms out," explained Professor Stephen Meyers, professor of geoscience at the University of Wisconsin-Madison.
Before you start worrying about the prospect of more hours to fill in the days though, fear not. The Moon is moving away from us at the incredibly slow rate of 3.82 centimetres a year.
But, in around 200 million years' time, days on Earth will be a full hour longer, lasting 25 hours.
Researchers studied evidence in Earth's rock record to trace changes in the planet's climate, a method known as astrochronology.
Speaking about the method, Prof Meyers said: "One of our ambitions was to use astrochronology to tell time in the most distant past, to develop very ancient geological time scales
"We want to be able to study rocks that are billions of years old in a way that is comparable to how we study modern geologic processes."
