A new study reconstructed the history of the relationship between the Earth and the moon, showing how the moon has affected the Earth over a period of 1.4 billion years. Now as it moves away, the days are meant to get longer, eventually even resulting in an added hour in the daytime.
Scientists from the University of Wisconsin-Madison and Columbia University found that days on Earth grew longer as the Moon inched further away.
The researchers integrated a sophisticated statistical method called "TimeOpt" with tools from astronomy and geology to get a better handle on our planet's uncertain past.
This is because Earth's movement is at least in part determined by the bodies around it, such as other planets and the Moon, which exert force on it. Using the data they were able to identify changes in the Earth's rotation, orbit, and distance from the moon throughout history.
Meyer, the study's co-author, said, "One of our ambitions was to use astrochronology to tell time in the most distant past, to develop very ancient geological time scales".
The Moon is moving away at a rate of 3.82 centimeters per year.
The new approach allowed them to detect the Earth's rotation and axis tilt during those times, and from that, they could determine the moon's location - and discovered that we enjoy longer days now than 1.4 billion years ago.
Meyers and his team wanted to know how the moon's orbit affects Earth's rotation. It turned out that because of the closer at the time, the distance of the Earth to the moon the length of day was only for 18.7 hours. This Meyers and colleagues demonstrated last year, when they published a paper showing interactions between Earth and Mars occurred 90 million years ago, based on layers of sediment in a Colorado rock formation. One layer was taken from a 55 million-year-old rock from the Walvis Ridge in the Atlantic Ocean, and the other taken from a 1.4 billion-year-old rock from Northern China.
"In the future, we want to expand the work into different intervals of geologic time", Malinverno said. By one estimate, days are getting longer at a rate of 19 hours every 4.5 bn years. In their study, they combined geological data with astrochronology and Bayesian inversion - methods used to account for unobserved variables and the uncertainty in our understanding of the solar system at the time.
Our faithful rocky companion used to lie far closer to our planet-close enough to alter the way it moves, researchers reported Monday in Proceedings of the National Academy of Sciences. "We are looking at its pulsing rhythm, preserved in the rock and the history of life", Meyers said in the statement.