An amazing surprise greeted NASA's OSIRIS-REx spacecraft as it touched down on the asteroid
The asteroid was not what it seemed -- according to research published Thursday
After it analyzed data from the spacecraft, NASA said it would have sunk into the asteroid
if it hadn't fired thrusters to lift off as soon as it collected the dust and rock samples because of its makeup.
That's because the surface of Bennu consists of loosely packed particles so lightly bound to each other that
if a person were to step onto the asteroid surface it would feel like a pit of plastic balls
If Bennu was completely packed, that would imply nearly solid rock, but we found a lot of void space