Lower reflectivity kept Earth from freezing under a fainter young sun
Though the sun was so much dimmer billions of years ago that the young Earth should have been literally freezing, the planet remained largely covered with liquid water. That was thanks to a substantially darker surface and a dearth of light-scattering clouds, a new study suggests.
“All other things being equal, Earth should have been frozen over for the first half of its existence,” says James F. Kasting, a geoscientist at Pennsylvania State University in University Park who was not involved in the research. “But it wasn’t.”
Note: To comment, Science News subscribing members must now establish a separate login relationship with Disqus. Click the Disqus icon below, enter your e-mail and click “forgot password” to reset your password. You may also log into Disqus using Facebook, Twitter or Google.