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ilan
06-06-2018, 12:14 PM
Days on Earth Are Getting Longer, Thanks to the Moon
Samantha Mathewson, Space.com Contributor | June 5, 2018 04:14pm ET



https://www.popsci.com/sites/popsci.com/files/styles/655_1x_/public/images/2017/06/earth_and_limb_m1199291564l_color_2stretch_mask_0. jpg?itok=Pjpr3D3F&fc=50,50This gorgeous photo of Earth with the moon in the foreground was captured on Oct. 12, 2015, by NASA's Lunar Reconnaissance Orbiter spacecraft. Credit: NASA/Goddard/Arizona State University


Days on Earth are getting longer as the moon slowly moves farther away from us, new research shows.

The moon is about 4.5 billion years old and resides some 239,000 miles (385,000 kilometers) away from Earth, on average. However, due to tidal forces between our planet and the moon, the natural satellite slowly spirals away from Earth at a rate of about 1.5 inches (3.82 centimeters) per year, causing our planet to rotate more slowly around its axis.

Using a new statistical method called astrochronology, astronomers peered into Earth's deep geologic past and reconstructed the planet's history. This work revealed that, just 1.4 billion years ago, the moon was significantly closer to Earth, which made the planet spin faster. As a result, a day on Earth lasted just over 18 hours back then, according to a statement from the University of Wisconsin-Madison.