A team of astrophysicists, geoscientists, chemists and life scientists affiliated with a host of institutions in Japan has found evidence that billions of years ago, the Earth's oceans were green.

Instead, they were a striking shade of green, shaped by ancient microbial life and the chemical composition of early seas. Now, scientists warn that Earth’s oceans may be shifting back to a ...

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 ...