What's happening in this video of a meteorite hitting Earth?
You may have seen this police dash-cam video of a meteor landing somewhere around Edmonton, Canada, which seems to show the meteor "burning up" more as it gets closer to the ground.
I was under the impression that most of the friction and burning up process occurred as meteors entered the atmosphere, so what is happening in this case?
To sleep, perchance to experience amygdalocortical activation and prefrontal deactivation.
As the object gets closer to the ground, the density of the atmosphere increases. As that happens, the friction increases and there is more "stuff" in the air to reflect the light thrown off by the object.
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Could be way off base here but...the thing is also crazy crazy hot. Does it steam up moisture in the air?
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Another factor to add to Clothahump's point about air density: many meteorites are both relatively weakly joined together (I think sandstone is much more solid than carbonaceous space rock.), and very far from uniform in composition. The description "dirty snowball" is cliched, but it still has a lot of truth to it.
As the meteorite heats up pockets of frozen gas often will sublimate to gas, with catastrophic and dramatic results. Instead of single body, say, one third of a meter across, there's a pocket of hydrogen ice towards the middle that flashes to gas when it gets hot enough. The pressure is enough to shatter the rock into smaller pieces, each approximately the size of your thumb. This has two effects that will increase the apparent brightness of the event: this shattering will expose new surfaces that are often chemically unstable for the conditions of atmosphere, pressure and temperature they are now subjected to - in short they'll often react with the oxygen in the air very energetically; the second event is that because of the speed the object is moving through the air, the friction has already been heating up the surface, causing the glow from the falling body, when the body explodes, suddenly there's much more surface area exposed to the atmosphere, all of which is still moving at the same approximate speed - so there's more material burning off, and glowing as it does so, once the body has broken up.
Well explained, guise. Another related quickie: do all natural objects that enter the atmosphere end up striking land or sea, or do some come in at such an angle that they can fly back out through the atmosphere, albeit on a rather slower orbit than previous?
To sleep, perchance to experience amygdalocortical activation and prefrontal deactivation.
Yes, that can happen. It happened rather famously, with this meteor:
To read up on this near miss, check out the Wikipedia article.
Amazing
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