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3 minutes seems like an awful long time to be staring out the window. But, I wonder how many of the injured people were observing the flash of light and the aftermath when the shockwave struck.
What has caused meteorite explosion in atmosphere?
Quote from: simplified on 23/02/2013 07:29:27What has caused meteorite explosion in atmosphere? and if it was done purely through heating the whole thing would turn into lava, but it clearly doesn't.
Some stones can explode in a fire.I saw it,but I don't know the reason.
Quote from: simplified on 25/02/2013 15:05:43Some stones can explode in a fire.I saw it,but I don't know the reason.Isn't moisture content one of the reasons why stones explode in the fire.However, as far as meteorites, I would have to imagine that asteroids orbiting with an orbit near Earth's orbit would tend to be dry due to the low pressures and the sun's heat. Asteroids originating near Pluto, or further out, and not spending a lot of time near the sun would tend to have a higher water content.However, if the meteorite consists mainly of water, it may be rapidly vaporized.Many metals will also burn when heated in contact with oxygen.
Quote from: simplified on 23/02/2013 07:29:27What has caused meteorite explosion in atmosphere?I posted something about this in another thread, but it should really be here, so I'll put a modified version of that here:-An Australian by the name of Dr. Karl (who is a living scientific database) does a phone-in in the middle of the night (Radio 5, 3-4 on Thursday mornings). Last Thursday he said something very interesting about the mechanism by which asteroids/meteors burn up or explode. I'd always thought it was down to friction and heating generated from that, but with a big lump of rock that's only going to do superficial damage. He explained that it's actually pressure that tears these rocks to pieces as the rock piles into gas which builds up in front of it, compressing the rock because it's easier to do that than to get out of the way. He also said that things which we are taught are incompressible like water are actually compressible - if you smack something into water hard enough it can be compressed to 3/4 of its normal volume (I don't know if that's a limit or just an example taken from some specific experiment), but it will apply to solid things too, thereby giving an insight into what can happen when a rock slams into the atmosphere at tens of thousands of miles an hour. He didn't explain the heating mechanism, but I would imagine it comes along for free as a direct result of the compression, and it would take compression of the rock to drive it to tear itself to pieces - we're talking about a rock of ten to twenty metres across being reduced to fragments, and if it was done purely through heating the whole thing would turn into lava, but it clearly doesn't.