Earth hasn’t always had a 24-hour day. Here’s what that means for the June solstice.
Over billions of years of Earth’s history, the time it takes Earth to rotate once on its axis has been getting longer.1.4 billion years ago, a single “day” lasted only about 18 hours. Changes in the gravitational dance between our planet and the moon are causing Earth’s day to get ever so slightly longer each year.
So, what is exactly is a solstice? And what has been influencing the lengths of Earth’s days? To learn more about this year’s summer solstice, see the full story HERE.
Victoria Jaggard, National Geographic science and space expert, is available for commentary out of Washington, D.C.
Kelsey Taylor, email@example.com, 202-912-6776