National Geographic News, Reporting Your World Daily

Monday, November 23, 2009

Photo: Earth Barely Big Enough for Life, Study Says


Email to a Friend	<< Back to Full Story

Earth is at the lower limit of how big a planet can be and still have the plate tectonics system needed to stabilize temperatures enough for life, according to a new study.

The findings suggest that scientists searching for habitable worlds should look for rocky planets two to ten times bigger than our own.

Image by Reto Stöckli, Nazmi El Saleous, and Marit Jentoft-Nilsen, NASA GSFC