Âé¶¹´«Ã½

Space

A day used to be less than 19 hours long 1.4 billion years ago

By Leah Crane

4 June 2018

Âé¶¹´«Ã½. Science news and long reads from expert journalists, covering developments in science, technology, health and the environment on the website and the magazine.

The moon has gotten further away, resulting in longer days on Earth

Gustavo Muniz/Getty

It’s not just you – the days really are getting longer. More than a billion years ago, the moon used to be about 40,000 kilometres closer, which made Earth spin faster. Back then, the days were less than 19 hours long.

Over the course of many thousands of years, Earth’s way of moving through the solar system goes through cyclical changes. The planet’s elliptical orbit shifts around the sun like a hula hoop, and the shape of the orbit itself wobbles between elliptical and nearly…

Sign up to our weekly newsletter

Receive a weekly dose of discovery in your inbox. We'll also keep you up to date with Âé¶¹´«Ã½ events and special offers.

Sign up

To continue reading, today with our introductory offers

or

Existing subscribers

Sign in to your account
Piano Exit Overlay Banner Mobile Piano Exit Overlay Banner Desktop