Large enantiomeric excesses in primitive meteorites and the diverse effects of water in cosmochemical evolution

Sandra Pizzarello, Devin Schrader, Adam A. Monroe, Dante S. Lauretta

Research output: Contribution to journalArticle

76 Scopus citations

Abstract

Carbonaceous chondrites are meteoritic fragments of asteroids that avoided the geological reprocessing of larger planets and allow laboratory probing of early solar-nebula materials. Among these, Renazzo-type (CR) chondrites found in Antarctica appear remarkably pristine and are distinguished by abundant organic materials and water-soluble molecules such as amino acids and ammonia. We present a comprehensive analysis of the organic composition of selected CR meteorites of different petrographic classification and compare compounds' abundance and distribution as they may relate to asteroidal aqueous processing and concomitant evolution of the mineral phases. We found that several CR compounds such as amino acids and sugar alcohols are fully represented in stones with no or minimal water exposure indicating a formation that, if solar, preceded parent body processes. The most pristine CRs also revealed natal enantiomeric excesses (ee) of up to 60%, much larger than ever recorded. However, aqueous alteration appears to affect CR soluble organic composition and abundances, in particular some diastereomeric amino acids may gauge its extent by the consequent racemization of their ee.

Original languageEnglish (US)
Pages (from-to)11949-11954
Number of pages6
JournalProceedings of the National Academy of Sciences of the United States of America
Volume109
Issue number30
DOIs
StatePublished - Jul 24 2012

Keywords

  • Abiotic molecular evolution
  • Clays
  • Primitive asteroids
  • Solar ices

ASJC Scopus subject areas

  • General

Fingerprint Dive into the research topics of 'Large enantiomeric excesses in primitive meteorites and the diverse effects of water in cosmochemical evolution'. Together they form a unique fingerprint.

  • Cite this