How Brazil Nuts Solved A Mystery About Asteroids

When Japan's Hayabusa spacecraft photographed the asteroid Itokawa in 2005, scientists were puzzled by what they saw: The total volume of boulders strewn about its surface were greater than the volume of the craters they were supposed to have come from. Now physicists have an answer... by studying the movement of nuts. » 7/16/14 7:20am 7/16/14 7:20am

This Ancient Asteroid Strike Was More Insane Than We Realized

Around 3.26 billion years ago — long before the dinosaurs — a massive asteroid measuring nearly 36 miles (58 km) across smashed into the Earth. Geologists have now reconstructed this cataclysmic event, and it was far, far bigger than we thought. Here's how things went down on that fateful day. » 4/10/14 12:00pm 4/10/14 12:00pm

Ask an astrophysicist anything you want about nearby asteroids!

Amy Mainzer is an astrophysicist at the Jet Propulsion Lab who builds instruments for space telescopes that allow us to study Earth's nearest neighbors, including asteroids, comets, and stars. She's here today to answer your questions about all the objects whizzing past Earth — and which ones we should be keeping our… » 11/21/13 9:30am 11/21/13 9:30am