Have you ever been responsible for stopping a collision?

Question: Have you ever been responsible for stopping a collision?
- Keywords:
  acheivement,
  end of the world,
  work
Asked by chaudhryf to Alan on 11 Mar 2014.
- Alan Fitzsimmons answered on 11 Mar 2014:
  
  No, because the only two asteroids we’ve found on collision course have been so small we didn’t worry about them before they exploded in our atmosphere.
  
  Right now I’me working with other scientists and engineers on how to build a spacecraft to stop a large asteroid colliding with us. We have never found any large asteroids that are on a collision course, but just in case we’re working on how to divert it onto a safe path!

Question: Have you ever been responsible for stopping a collision?