News Earth

A moon-forming cataclysm could have also triggered Earth’s plate tectonics

The hypothesis could help in the search for other Earthlike worlds

An illustration of a planet crashing into Earth, setitng off a huge explosion and launching chunks of rock into space

A hypothetical, Mars-sized planet might have collided with Earth about 4.5 billion years ago and birthed the moon. The impact could have kick-started subduction on Earth, researchers suggest.

Tobias Roetsch/Future Publishing via Getty Images

By Nikk Ogasa

THE WOODLANDS, TEXAS — Vestiges of a moon-forming cataclysm could have kick-started plate tectonics on Earth.

The leading explanation for the origin of the moon proposes that a Mars-sized planet, dubbed Theia, struck the nascent Earth, ejecting a