Days on Earth could be extended to 25 hours.
Days on Earth could last an hour longer in the future
An additional hour may be added to the day as the Moon gradually drifts away from Earth - slowing the planet's rotation and subsequently making days longer.
Experts have come up with a statistical method combining astronomical theory with geological observation and calculated that a day lasted just 18 hours 1.4 billion years ago.
They do expect days to reach 25 hours at some point but explained that it will take around 200 million years for the extension to happen.
This is because the Moon moves 1.5 inches further away from Earth each year in a process that is known as lunar recession.
Professor Stephen Meyers, from the University of Wisconsin-Madison in the US, said: "As the Moon moves away, the Earth is like a spinning figure skater who slows down as they stretch their arms out."