Today, we got some hard numbers on the asteroids, comets and other objects whizzing through space near Earth.
Astrophysicist Amy Mainzer took a break from asteroid-hunting at JPL to answer a couple of our most burning questions about asteroids, comets, and whatever else is just over our heads. Among the questions she answered were just how likely an Armageddon-sized asteroid crash was ("The only asteroid we know of that's as big as Texas [Ceres] is parked safely and soundly in the Main Asteroid Belt and isn't going anywhere. Whew!"), just where Earth Trojan asteroids might come from ("there are some theories that postulate that they might be leftovers from the solar system's birth. But my guess is that they're more recent captures - kind of like a leaf that gets temporarily dragged into an eddy in a river, then eventually gets booted back out"), and also gave us some amazing information about just how much there is out there still left to find: