The "Blue Marble" was the first photo of the whole Earth and the only ever taken by a human. Fifty years on, new images of ...

But while lifeless during that time, the planet was already covered by vast oceans dotted with hydrothermal vent systems that released large amounts of ferrous iron into the water. The earliest ...

The changes in ocean chemistry were gradual. The Archaean period lasted 1.5 billion years. This is more than half of Earth’s ...