Organic Matter Can Survive Atmospheric Entry

Porfiry writes: "Astrobiologists have come to a number of interesting conclusions after observing the 1999 Leonids. "Last year's Leonid meteor storm yielded rich research results for NASA astrobiologists," said Dr. Peter Jenniskens. "Findings to date indicate that the chemical precursors to life -- found in comet dust -- may well have survived a plunge into early Earth's atmosphere. We discovered that most of the visible light of meteors comes from a warm wake just behind the meteor, not from the hot meteoroid's head," said Jenniskens. This warm wake has just the right temperature for the creation of life's chemical precursors." Note that this year's Leonids will be brightest on November 16 and 17.

Without Fail

[chaobell]

I can tell you right now what the weather will be like on the 16th and 17th without so much as looking out the window. It will be completely overcast. Every time we have a neat astronomical event (meteor shower, lunar eclipse, etc) around here, the Cloud Factory goes into overdrive. Bah, I say. Bah.

Other supporting evidence

[tesserae]

A recent issue of Science contained a paper [sciencemag.org] on the famous (or should that be "infamous"?) martian meteorite [sciencemag.org] earlier reported to contain evidence of life. The new paper concluded that the highest internal temperature experienced during entry into Earth's atmosphere was no more than 40 C -- in other words, quite a bit below sterilization temperatures for most microorganisms.

The authors conclude that "these data support the hypothesis that meteorites could transfer life between planets in the solar system." Not just the chemical precursors for life, as Jenniskens et al. are reporting -- they state that "[e]very million years, ~10 rocks larger than 100 g are transferred in just 2 to 3 years", and point out that microorganisms and bacterial spores can survive 5 years in space, as shown by experiments on NASA's Long Duration Exposure Facility (LDEF).

Looks like panspermia's going to make a comeback... the authors of the Science paper even suggest there's no reason to quarantine the rocks from a Mars sample return mission, because whatever's there, we've already got.

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