Giant regions of the mantle where seismic waves slow down may have formed from subducted ocean crust, a new study finds.

But there is no evidence for large-scale magma seas in Earth's history. Also, the moon does have some volatile elements, like water, trapped in rock — but a giant-impact, giant-energy event ...

Some studies have suggested that they're material from the ancient Earth — either a layer of primordial unmixed rock from the planet's formation or a leftover hunk of the giant space rock that ...

In orbit around the white planet is a single cratered moon. You are gazing on Earth in the Cryogenian period, 700 million years ago. This is about three times as long ago as the earliest dinosaurs ...

New research has revealed how massive ancient glaciers acted like giant bulldozers, reshaping Earth's surface and paving the way for complex life to flourish. By chemically analyzing crystals in ...

which indicates that Earth and the moon evolved from the same clump of material. The leading explanation for all of these mysteries is known as the giant impact hypothesis. According to this story ...