As you've probably heard already because you're bound to have at least one friend on Facebook or IRL who's constantly freaking out about conspiracies and the imminent end of the world and collapse of society, a meteor exploded above the Chelyabinsk region of central Russia earlier today. It inured over 900 people, at least two of them seriously.Since then, the web has been flooded with dashcam videos of the meteor streaking across the sky before exploding, sending a shockwave that shattered windows and knocked people to the ground. It wasn't immediately known what caused the explosion, with some speculating it was either UFOs, a missile test gone wrong or – from the more misguidedly pensive among them – perhaps America invading 25 years too late:
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Brendan Owens: It seems as if it was one major meteor. When we get a particularly large one, we call them fireballs, which are much bigger than a normal shooting star. It'll be interesting to see when people start to find pieces that survived the atmosphere, because then we'll see whether they're of a stony composition or a more metallic composition, which will tell us something more about the original object that entered the atmosphere.How come nobody saw this coming? I thought there were people watching the skies all the time?
Yeah, it was a little bit of a random one. We can’t account for everything, unfortunately, and when it comes to smaller objects, they’re trickier to spot. On top of that, this has actually come from a sunward direction, so you can't see that if you’re an amateur astronomer.
Skip to 1:20 for the shockwave.What caused the explosion in mid-air? Was that when it broke the sound barrier?
That’s still under debate. It was definitely travelling at a fast enough speed to break the sound barrier, so there would have been a sonic boom, but there are recorded scenes that show another explosion, indicating that the actual object blew up. Something similar happened in the Tunguska event in 1908. A meteor came crashing through the atmosphere, but into a much less populated area, exploded above the ground and flattened trees for about 800 square miles.
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I’d say a lot of the structural damage – although I haven't seen many photos of it – indicate that an object or objects smashed into buildings as well as the shockwave.I mean, there was that zinc factory that exploded.
Yeah, they’re still trying to work out if something inside that building caused it to explode, so we can’t be certain about that. But the meteorites themselves do fall from the sky, so depending on how many fragments there were, that's the equivalent of dumbbells falling from the sky, which are obviously going to do some damage.Is there any estimation so far on the size of this particular meteor?
The Russian scientific council have estimated it as about 10 tonnes, but the original object might have weighed even more. So that's 10 tonnes of meteor travelling at the speed of 33,000mph.That's a fun thought. And now people are saying that there might be more coming.
It’s unlikely that there'll be more. It seems to be a cosmic coincidence – there's no physical link between the asteroid (DA14) that's flying close today and the one that struck this morning. They're on a completely different trajectory, so it really is just a very surprising coincidence. Another thing is that this asteroid has been tracked by NASA since last year, so we know it’s not going to hit any, say, communication satellites, or anything like that.
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With 2012 DA14, we know it’s a stony asteroid and about 50m across. So, depending on stress and strains as it passed through our atmosphere, it would be large enough to cause major devastation of a city. It wouldn't be a civilisation-killer, though; the damage would be relatively localised.Where should budding doomsday preppers be looking if they want to catch a glimpse of DA14?
It'll be between the handle and the bucket of the Plough at around 9PM, so if you look in there with binoculars or a small telescope, you should see something move. To put the speed of this object into perspective, it covers the same distance of how the full moon appears in the sky about every 45 seconds. So, every 45 seconds, it will have done a moon-sized jump. It keeps moving so you actually don’t want something where you’re really zoomed quite close – you’d want a big wide view to see it.Thanks, Brendan, I'll be sure to whip out my binoculars tonight.Thanks to Gleb Timofeev and Alina KhametovaFollow Henry on Twitter: @Henry_LangstonMore times people have been worried about the world ending:Making Friends at Stonehenge at the End of the World I Hung Out in the Town Everyone Said Would Survive the ApocalypseThis Guy Is Convinced There Really Will Be a Zombie Apocalypse
