Discover how scientists have used iron isotopes to determine the likely origin of the Mars-sized planet named Theia.

Roughly four and a half billion years ago the planet Theia slammed into Earth, destroying Theia, melting large fractions of ...

Apollo samples provide evidence: Researchers analyzed Moon rocks brought back by the Apollo missions and, for the first time, ...

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 ...

Scientists traced the Moon's parent planet Theia to the inner Solar System, solving a 4.5-billion-year mystery.

A groundbreaking study in Nature has shaken up our understanding of the moon’s formation. This research suggests that the moon was born during Earth’s earliest days, revolutionizing the timeline of ...

The formation of the Moon may have come harder on the heels of Earth's birth than we thought. According to a new analysis by researchers from the US, France, and Germany, Earth's constant companion ...

To our best of our understanding, the Moon formed from Earth following a colossal impact. A Mars-sized world we nicknamed ...

Scientists continue to explore the deep story of how Earth and the moon formed. One idea has gained attention because it ...

Billions of years ago, so the theory goes, something around the size of Mars smacked into Earth, spewing a whole bunch of dirt into space that eventually coalesced to form the Moon. This is called the ...

New research suggests that Theia, the object whose collision with Earth is theorized to have caused the formation of the moon ...

Scientists have gone back and forth about explanations for the moon's formation for decades, with the general consensus being that it formed during some type of cosmic collision between Earth and a ...