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Wet, Carbonaceous Asteroids: Altering Minerals, Changing Amino Acids. + Water. Aqueous alteration has substantially affected the mineralogy of many carbonaceous chondrites. An unaltered chondrule. Amino Acids.
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Wet, Carbonaceous Asteroids: Altering Minerals, Changing Amino Acids + Water Aqueous alteration has substantially affected the mineralogy of many carbonaceous chondrites. An unaltered chondrule
Amino Acids Amino acids are characterized by the presence of an amine group, NH2, and a carboxylic acid group, COOH, joined to side chains (R). Two examples are shown. NASA /Mary Pat Hrybyk-Keith Amino acids also can have symmetrical differences in their structures, mirror images of each other. Shown are L-isovaline and D-isovaline.
Changes in the Amino Acid Mix with Aqueous Alteration Modified from Glavinet al., 2011. Increasing alteration causes the abundance of -Alanine to increase, others to decrease.
Changes in L/D with Aqueous Alteration Graphic prepared with data from Glavinet al. (2011). Aqueous alteration appears to have enriched isovaline in the L structure, suggesting that this could have happened on the early Earth or that carbonaceous chondrite asteroids added an already asymmetrical mix to the Earth.