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The First Discovered Tiny Asteroid of 2014 Has Harmlessly Impacted Earth

2009 asteroid

A bright meteor lit up the sky over the Netherlands in 2009. If anyone saw it, the tiny asteroid impacted Earth yesterday should be as bright as it. *Image source: delmagyar.hu

Astronomers discovered a tiny asteroid just before it impacted the Earth. This is not science fiction, it is what just happened. Actually it’s not the first time, but the second one. But don’t panic: It was very small, probably just a few meters in diameter, and burned up harmlessly in our atmosphere. But after this event, it underscores the need to keep our eyes open.

This asteroid is named 2014 AA, the first asteroid discovered this year. It was detected by the Mount Lemmon Survey using a 150 centimeter telescope located on a mountain in Arizona. The first image of the asteroid was taken on Jan. 1, 2014, at around 01:20 EST – telescopes work whenever the sky is clear, holidays or no. The rock was faint, at about magnitude 19; the faintest star you can see with naked eye is 150,000 times brighter than this one! But an orbital calculation suggested it was very close to Earth, and getting even closer.

As a matter of fact, as the Minor Planet Electronic Circular discovery announcement said:” It’s virtually certain that 2014 AA hit the Earth’ atmosphere on 2014 Jan. 2.2+/-0.4”— meaning about 05:00 UTC Jan.2, midnight EST, and just two days ago. It most likely burned up over the Atlantic, somewhere between Africa and South America.


The possible path of 2014 AA ramming through the atmosphere of Earth, locating in Atlantic southwest to Canary Islands. *Image source: Asteroid Initiatives, LLC

According to its brightness, it was probably around two to four meters across, about the size of a car. Small objects like this generally disintegrate as they ram through the Earth’s atmosphere at high speed, so this object would never become a big threat to us.

This is the second asteroid in history that was seen before it hit us; the first one was 2008 TC3, which burned up over Sudan in Africa in 2008. 2008 TC3 was found just a day prior to its atmospheric entry. Other rocks have been found in the past that gave us a very close shave, and often small asteroids that in fact hit us go undetected until someone looks up and sees them! This is because they are so small that makes them very faint and difficult to detect. Because they are close by they are also prone to move rapidly across the sky, making them more difficult to find. The 19-meter wide asteroid that blew up over Russia last year was undetected until it hit, for instance.

Of course, this underscores how seriously we should take asteroid impacts. Although 2014 AA was not a big danger, there are million bigger rocks out there that cross Earth’s orbit, big enough to result in real damage should they hit us. And they will, given enough time.

That is why we have to keep scanning the skies, locating and characterizing the asteroids. Both B612 Foundation and NASA are working on better detection approaches, but that is 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, however, we are a long way from being able to implement it.

As usual, I’d say that you shouldn’t run around in circles panicking over that; after all, such events are rare to see. But if we do nothing at all, we are guaranteeing that a big impact will happen sometime in future. Like some other problems, the prevention cost is small compared to the cost of doing nothing. We can afford the former, but not the latter.

SourceBad Astronomy