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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Four and a half billion years ago, a planet named Theia slammed into the early Earth — a cosmic catastrophe that forged the Moon and reshaped our world forever. Republican blasts "immoral" Trump ...