"This is maybe the first direct evidence that we've preserved the proto-Earth materials." When you purchase through links on our site, we may earn an affiliate commission. Here’s how it works.

About 4.5 billion years ago, the most momentous event in the history of Earth occurred: a huge celestial body called Theia collided with the young Earth. How the collision unfolded and what exactly ...

Water is everywhere on Earth, but nobody has ever been able to determine conclusively how it got here. Scientists know that the very early Earth was far too hot to hold water or water vapor, but then ...