Lifeboat Foundation

For nearly 60 million years, our home planet was likely frozen into a big snowball.

Now, scientists have discovered evidence of Earth’s transition from a tropical underwater world, writhing with photosynthetic bacteria, to a frozen wasteland – all preserved within the layers of giant rocks in a chain of Scottish and Irish islands.

The team, led by researchers from University College London (UCL), examined more than 2,000 grains of zircon from 11 sandstone samples, taken from up to 200 meters within the 1.1 km-thick (0.7 miles) Port Askaig formation, and the older, underlying Garbh Eileach formation, which is 70 meters thick.