Laura Poppick
Glaciers May Have Covered the Entire Planet—Twice
This story was originally published by Knowable Magazine.The Earth has endured many changes in its 4.5-billion-year history, with some tumultuous twists and turns along the way. One especially dramatic episode appears to have come between 700 million and 600 million years ago, when scientists think ice smothered the entire planet, from the poles to the equator—twice […]