The Earth formed over 4.6 billion years ago out of a mixture of dust and gas around the young sun.

This graphic illustrates how the moon may have formed after multiple collisions on Earth. Moon- to Mars-sized impactors strike the Earth and leave a disk of debris orbiting the planet.

The Moon's formation may not just have smashed Earth -- it may have stretched our planet into a potato for millions of years afterwards.

Billions of years ago, so the theory goes, something around the size of Mars smacked into Earth, spewing a whole bunch of dirt into space that eventually coalesced to form the Moon. This is called ...

New research reveals that the abundance of so-called highly siderophile, or metal-loving, elements like gold and platinum found in the mantles of Earth, the moon and Mars were delivered by massive ...

But new research shows that Earth and the Moon must have formed much later -- perhaps up to 150 million years after the formation of the solar system.

This mode of formation would explain the matching isotopic ratios of the Earth and moon, because they both would have formed from the same general region of the protoplanetary disk.

The moon formed from the collision of the Earth with a Mars-sized object named Theia. Now, astronomers have answered mysteries around this ancient event.

A new model that takes into account the distribution of various metals in the crust now suggests that the Moon-forming giant impact (MGI) could have occurred much later—but only if the Earth ...

A new study of the tungsten present in both the Moon and Earth show a crucial difference that confirms an explosive, interconnected past.