Taxonomy term

giant impact theory

Moon formed from pulverized Earth mantle

Scientists have long thought that the moon was formed when an impactor crashed into Earth, some 100 million years after the planet’s formation. But details of this collision, and how the moon formed in its aftermath, remain puzzling. Now, researchers have found new potassium isotopic evidence that suggests the moon condensed from a superheated cloud of Earth’s mantle material after an extremely violent collision vaporized the impactor and much of the proto-Earth.

23 Jan 2017

New lunar research answers old questions, poses others

From its close perch in the sky, the moon has long mystified artists, lovers and scientists. Now a quartet of recent papers — all of which touch on the moon’s violent birth and turbulent infancy — may help scientists put two long-standing lunar mysteries to rest, while deepening a third enigma and suggesting a speculative solution to a fourth.

23 Oct 2014

Moon could have formed from Earth after all: Reviving and revising the giant impact theory

Scientists are revisiting the age-old question of how Earth’s moon formed. New models indicate that it could have been born from the Earth following a giant collision after all.

The idea of a moon-forming collision is not new. The giant impact theory — the idea that a catastrophic collision about 4.5 billion years ago between Earth and a protoplanet about half Earth’s size created a disk of molten rock, gas and debris that consolidated to form the moon — was first set forth in the mid-1970s.

04 Feb 2013