25-Hour Ahead? How Moon's Slow Drift Could Increase Day Length

The Moon has always fascinated people, but new research shows it's slowly moving away from Earth. This surprising discovery comes from studying ancient rocks, and scientists at the University of Wisconsin-Madison found that this gradual drift of the Moon from Earth could have significant effects.

The study reveals that the Moon is moving away from Earth at a rate of approximately 3.8 centimeters per year. This gradual drift will eventually extend the length of Earth's days to 25 hours, but only in about 200 million years. The research also indicates that 1.4 billion years ago, a day on Earth was just over 18 hours long.

This phenomenon is mainly due to the gravitational interactions between the Earth and the Moon, especially the tidal forces that each body exerts on the other.

"As the moon moves away, the Earth is like a spinning figure skater who slows down as they stretch their arms out," said Stephen Meyers, a professor of geoscience at the University of Wisconsin-Madison.

"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," he added.

The Moon's recession is not a new discovery; it has been known for decades. However, the University of Wisconsin-Madison's study delves deeper into the historical and geological context of this phenomenon. By examining ancient geological formations and sediment layers, researchers have traced the history of the Earth-Moon system over billions of years. Their findings suggest that Moon's current rate of recession is relatively stable, but it has fluctuated over geological timescales due to various factors, including the Earth's rotational speed and continental drift.