Longer Days


Moons orbit planets, planets orbit the sun. Round and round they go forever locked in gravitational harmony. Sunrise, sunset, new moon, full moon, every day a 24 hour certainty. Foundations so fundamental we take them for granted. Not so fast – days haven’t always been 24 hours. Truth is, days are getting longer.

New astronomical research dubbed astrochronology suggests that recently as 1.4 billion years ago Earth completed a day in 18 hours. Science credits interaction of Earth/Moon tidal forces for lunar orbit spiraling away from Earth at 1.5 inches a year.

Gravity is a cosmic wonder, proximity of mass dictates rate of rotation. 18 hour day Earth was driven by a vastly closer Moon. Over time rotation slows as the Moon spirals away. Less pull, less spin, longer days.

https://www.space.com/40802-earth-days-longer-moon-movement.html?utm_source=sdc-newsletter&utm_medium=email&utm_campaign=20180606-sdc

 

This 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