Friday, October 2, 2009

Catch a falling star

Part of my job is so incredibly cool. I get to meet people who do the damnedest stuff and are just so totally wrapped up in their work, then I get a peek into a corner of the universe I had not seen before. Today I visited a scientist with NASA who works in Exobiology. Yup, that really is the name of his department. I had to think about that one a bit, exobiology. Lotsa possibilities in that name, huh?

He grinds meteors into powder, extracts the organics with water and compares the structural isomers of the sugar acids. So there is a lot of formaldehyde, a 1-carbon building block, floating around in space. When formaldehydes react and form a 2 or 3 or 4 or 5 or 6-membered carbon chain, and you get some water action thrown in, you get some very interesting left-hand vs right-hand structure stuff going on. Now since all of this meteoric carbon chains are formed by collisional chemistry, there ought to be as much left-handed compounds as right-handed ones, it just depends how things end up after the collision. This is very different than life on earth, where molecules made by organisms are overwhelmingly left-handed, because they are made by left-handed enzymes, not by random collisions. What this scientist is seeing, though, is the short chains ARE pretty much equally left- and right-handed. The 4 carbon chains are about 2:1, the 5 carbon chains are about 10:1 one way. By the time he gets to looking at the 6 carbon chains, they are all alike, no mirror images. Now THAT is unexpected, to say the least.

I get the "exo" part, but I would not have called collisional synthetic reactions "biology". Just reading the posters on the walls, I have to say there is some unique and strange chemistry being studied on that floor. Outta this world, I'm just sayin'.

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