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The Skeptics' Guide to the Universe
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Noah Wiles's profile photoGratten Darmody's profile photoStacy Stevens's profile photoJennifer Bennett's profile photo
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"People were claiming that they were burnt by meteorites, and that there were fumes, weird fumes that even caused one to pass out apparently and had to be taken to the hospital. And right there that's gotta raise some skeptical eyebrows because meteorites generally are not hot, they're traveling in space in the close to absolute zero so after a brief little journey, fire journey through the atmosphere isn't going to make that much of a difference, and it doesn't conduct heat very well … they are not hot, they are generally pretty cold.  And the fumes, the whole thing with the fumes is silly."  http://theskepticsguide.org/archive/podcastinfo.aspx?mid=1&pid=400 (11:34 - 12:15)

- Meteoroids are usually relatively hot by the time they are reaching the Earth's atmosphere for the same reason as the surface of the Moon can reach 390 K by the day at the equator.

As with the moon surface, the continuous direct exposure to sunlight for several terrestrial days with the energetic intensity of the sunlight that reaches the Earth's upper atmosphere is enough to heat them above what we would consider warm (some 300 K).

Of course this would only apply to metallic or stony meteoroids, the icy meteoroids would start to sublimate before their surface could reach a relatively warm temperature (well above water's solid–gas phase line).

I also believe that the extreme temperatures that the outer surface of the meteor attains will contribute significantly to increase the temperature of the outer layer of the resulting meteorites, despite the short time available to its conduction (although the metallic ones will heat up much faster).  An evidence of this are the fused materials commonly found in the meteorites that have been recovered.

That said, I have the conviction that they simply found what they were looking for, terrestrial diatoms (i.e., Earth-born diatoms), or more accurately, fossil terrestrial diatoms.  Fortunately, they didn't find a pound sterling coin inside the meteorite.  Otherwise they would have claimed that Queen Elisabeth II was also an extraterrestrial organism.

Reference:
- Vasavada A et al. Near-surface temperatures on Mercury and the Moon and the stability of polar ice deposits. Icarus (1999) vol. 141 (2) pp. 179-193 sciencedirect.com/science/article/pii/S0019103599961754 
(p. 182) FIG. 2.  Surface temperature as a function of local time at the equators of Mercury (top) and the Moon (bottom).
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Have them in circles
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SGU is nearing 26 million downloads. 26,000,000! Thanks for tuning in.
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Matti Munnukka's profile photoKimberly Chapman's profile photoBob Marshall's profile photoGlenn Elert's profile photo
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You are correct I do not have a FB account.  I just add all my other skeptic podcasts to my G+. In addition to SGU I will now chek my account daily.
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Have them in circles
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A podcast about science, bad science, and how to tell the difference.
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One of the most popular science podcasts on the interwebz, featuring Steve, Bob, and Jay Novella, Evan Bernstein, and Rebecca Watson.