Was chicken little right about the sky falling? Possibly, since hundreds of tons of space debris falls to earth every single day. Most of these particles are microscopic, but the threat of a fireball the size of a football field is possible. Now the idea that our planet orbits in a shooting gallery of comets and asteroids is getting serious attention. In order to learn more about asteroids scientists need to get up close and personal with them. Watch incredible exclusive coverage of NASA's just completed mission to an asteroid. This dramatic, nail-biting mission is the first-ever attempt to land on an asteroid. Go inside the super-sanitized clean-room at Johnson Space Center, with cosmic mineralogists analyzing precious meteorites. Learn how meteorites may have played a role in brining life to earth. Join scientists in investigating how comets and asteroids may have helped re-shape evolution.