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 ...

Scientists proposed a novel idea on Wednesday that could solve two of the world's mysteries at once — one that passes over our heads every night, and one that sits far below our feet. The first ...

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 ...

There may be chunks of an alien planet hiding within Earth. Scientists have long theorized that Earth collided with a planet called Theia 4.5 billion years ago, creating the Moon that we now see every ...

Researchers have long suspected that the Moon was formed after a Mars-sized protoplanet, dubbed Theia, smashed into the primordial Earth some 4.5 billion years ago. The literally Earth-shattering ...

About 4.5 billion years ago, a colossal impact between the young Earth and a mysterious planetary body called Theia changed everything—reshaping Earth, forming the Moon, and scattering clues across ...

Astronomers have long suspected that the Moon formed roughly 4.5 billion years ago when a hefty planet-in-the-making called Theia collided with a young Earth. Now, researchers have found evidence that ...

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About 4.5 billion years ago, the most momentous event in the history of Earth occurred: a huge celestial body called Theia collided with the young Earth. How the collision unfolded and what exactly ...