A rocket set to take off Thursday evening from Cape Canaveral, Fla., is part of a mission by NASA and the University of Arizona to send a robot to an asteroid. The goal: Bring back ancient dust.
The asteroid is called Bennu, and it's basically a giant rubble pile, shaped something like a spinning top. But it's a very special rubble pile. Scientists believe it has been moving through space untouched for about 4.5 billion years, making it a time capsule from when our solar system was just starting to form.