Around 700 million years ago, Earth was a very different planet—gripped by extreme deep freezes during the Cryogenian period. Enormous glaciers, kilometers thick, stretched across vast regions, ...

Imagine floating in space, gazing on a frozen white orb. The ball hangs in the void, lonely and gleaming in the light from its star. From pole to equator, the sphere is covered in a thick crust of ice ...

Earth was so cold at the time that the oceans were frozen all the way to the equator, and life only existed in the oceans ...

This is a fossilized coral — one of dozens scattered across the Indian Ocean archipelago of the Seychelles. It is a piece of history, hidden in plain sight. It tells of a time 125,000 years ago ...

In the 18th century, French scientists thought they had identified the location of the equator. But they got it wrong. Thousands of years earlier the pre-Incas were able to plot its location ...