Imagine the world’s oceans with their beautiful blue color. Now, imagine that the same oceans were green. This is the intriguing possibility suggested by new research from Nagoya University in Japan.

Scientists have discovered evidence that Earth's oceans were once green, hinting that this could be a marker of early life, ...

But while lifeless during that time, the planet was already covered by vast oceans dotted with hydrothermal vent systems that ...