Huge space rock rattled Earth 3 billion years ago

The size of the asteroid that may have killed the dinosaurs (Chicxulub) and even Mount Everest look tiny compared to a space rock that may have slammed into Earth 3.26 billion years ago. 

AGU

An asteroid almost as wide as Rhode Island may have plowed into Earth 3.26 billion years ago, leaving its mark in South Africa’s Barberton greenstone belt.

Hitting the planet at a speed of 20 kilometers per second, the 37- to 58-kilometer-wide space rock could have jolted Earth with the force of a magnitude 10.8 earthquake and set off tsunamis thousands of meters deep, researchers report in a paper accepted for publication in Geochemistry, Geophysics, Geosystems.

It is the first time scientists have been able to calculate the size of the impact and its effect on Earth.

The width of Hawaii and the Chicxulub crater seem extremely small compared to the hole gouged out by an asteroid that was at least 37 kilometers wide. AGU

Ashley Yeager is the associate news editor at Science News. She has worked at The Scientist, the Simons Foundation, Duke University and the W.M. Keck Observatory, and was the web producer for Science News from 2013 to 2015. She has a bachelor’s degree in journalism from the University of Tennessee, Knoxville, and a master’s degree in science writing from MIT.