To our best of our understanding, the Moon formed from Earth following a colossal impact. A Mars-sized world we nicknamed Theia slammed and merged with the primordial Earth, throwing material into ...

New simulations reveal that the Milky Way’s odd split between two chemically distinct groups of stars isn’t a universal ...

ALMA observations of interstellar object 3I/ATLAS show increasing methanol production near the Sun, with hydrogen cyanide ...

"The most convincing scenario is that most of the building blocks of Earth and Theia originated in the inner solar system. Earth and Theia are likely to have been neighbors." ...

Theia, the world that helped form the Moon, came from the Solar System. Chemical clues in Earth and Moon rocks reveal this ...

Later in December, the 3I/ATLAS interstellar comet will get as close to Earth as it ever will. Here's what to know.

Moon’s precursor planet, Theia, disappeared billions ago, leaving scientists no direct chemical evidence to support the hypothesis. Now a team of astromers in France, Germany and the United States ...

Little is known about the long-destroyed moon-forming planet, Theia. But it may have been born in the inner solar system—just like Earth—a new study suggests ...

Analysis of the second confirmed interstellar comet to visit our solar system suggests that the alien body could be covered ...

When a meteor streaks across the sky, it's not just beautiful. It's nature's way of delivering a time capsule to Earth.

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.

In the dense environment of the early universe, dark matter particles would collide with, and annihilate, each other, ...