Scientists have dated the birth of the Solar System to about 4.57 billion years ago. About 60 million years later a “giant impact” collision between the infant Earth and a Mars-sized body called Theia ...

It’s been 30 days since Uranus first appeared in the sky. At first, it looked like our Moon had found itself a stellar partner. But then, we understood something much, much bigger was headed our way.

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Last time a stray planetoid the size of Mars smashed into Earth, it scattered our planet's young crust into space, where gravity glued those particles into what we now call the Moon. Trump threatens ...