Although the Earth’s been decidedly blue for 600 million years, rising populations of phytoplankton caused by rising ...

Imagine a world where the vast oceans glimmered not in deep blue, but in brilliant green. A time when Earth’s seas, ...

Of all the planets in our solar system, the Earth is the only one that—as far as we know—supports life. So why is our planet alone so hospitable? In part, we owe our existence to a process ...

For a long stretch of Earth’s history, our planet might have looked green from a distance, instead of the pale blue dot we know today. Earth’s green period, which lasted from around 3 billion ...