I would have thought we already had one. If we are going to be sucking asteroids into our space shared by the moon we really should have a plan that is tested in case one gets loose! I know we will need this “Shotgun” to travel anywhere beyond our atmosphere. I was hoping more for a “laser” but shotgun, sling shot, whatever… get it ready before our technology has us dodging space rocks here at home!
http://nypost.com/2015/09/20/nasa-working-on-space-shotgun-to-blast-asteroids/