Today in terrifying news about our total inability to spot incoming asteroids, we have a reality check for you.
For while the existence of reassuring-sounding programs like Nasa's Near Earth Object Program, ESA's CEO Coordinating Centre and the Space Weather Coordination Centre, we really have no idea what we're doing when it comes to preventing a devastating asteroid impact.
As evidence of that fact we present two events. The first took place almost exactly a year ago, when a massive asteroid exploded over Russia and injured 1,500 people with absolutely no warning at all. The other occurred on Monday, when an asteroid precisely tracked and monitored by Nasa totally failed to show up, because we lost it.







Global map showing possible impact locations of 2014 AA based on Catalina Sky Survey images (blue band), and probable impact location based on infrasound data (red dot).



http://neo.jpl.nasa.gov/news/news182a.html