It’s only the second time in history that an asteroid was seen before it hit us; the first was 2008 TC3, which burned up over Sudan in Africa in 2008. That one was also discovered just a day before atmospheric entry. Other rocks have been discovered in the past that gave us a very close shave, and usually small asteroids that actually hit us go undetected until someone looks up and sees them! That’s because they are so small: That makes them faint and hard to detect. Because they are close by they also tend to move very rapidly across the sky, making them harder to find. The 19-meter wide asteroid that blew up over Russia last year was undetected until it hit, for example.

It’s possible some satellites may have observed the entry of 2014 AA, and hopefully we’ll get an image or two. Stay tuned.

And of course this underscores how seriously we need to take asteroid impacts. While 2014 AA wasn’t a threat, there are a million bigger rocks out there that cross Earth’s orbit, big enough to cause real damage should they hit us. And given enough time, they will.

That’s why we need to keep scanning the skies, locating and characterizing these asteroids. Both NASA and the B612 Foundation are working on better detection methods, but that’s only the first step; we also need a plan in place should we find one with our number on it. B612 is working on that, but we’re a long way from being able to implement it.

Asteroid 2014 AA: Harmless impact over Atlantic Ocean last night.