The moon has been Earth's constant companion for approximately 4.5 billion years, escorting the planet during its myriad journeys around the sun. While its origins are a little hazy - it cannot be ...

Roughly four and a half billion years ago the planet Theia slammed into Earth, destroying Theia, melting large fractions of Earth’s mantle and ejecting a huge debris disk that later formed the moon.

'Theia' is a long-vanished world, a planet-sized body thought to have smashed into the early Earth and that helped to form the moon. A new study has now analysed ancient lunar and terrestrial rocks to ...

(CNN) — Scientists widely agree that an ancient planet likely smashed into Earth as it was forming billions of years ago, spewing debris that coalesced into the moon that decorates our night sky today ...

Scientists think a planet may have crashed into Earth 4.5 billion years ago, creating the moon. This alien planet, Theia, was thought to have completely disappeared in the collision. A new study ...

Two gigantic blobs of dense rock hundreds of miles tall sit deep inside Earth. New research suggests these blobs are remnants of a planet that hit Earth 4.5 billion years ago. The collision of Earth ...

A new study of metal ore deep inside the moon is offering fresh evidence that Earth's natural satellite was formed by an ancient planet crashing into Earth long ago. This long-theorized interplanetary ...

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