Researchers have found that Earth’s first oceans may not have been blue at all like today. Instead, they may have gleamed in ...

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

The wildlife series narrated by David Attenborough explores the planet's green seas. From enchanted forests to undersea prairies, they teem with life. Show more It's our green seas, not the blue ...

Keep reading to learn more about Earth's different layers, its atmosphere, and what makes the "blue planet" unique. Earth is made out of different layers, and those layers get hotter and more ...