Isotopic evidence for extraterrestrial non-racemic amino acids in the Murchison meteorite
Article Abstract:
Further investigations of the amino-acid enantiomers in the Murchison meteorite support earlier findings that the L-enantiomer excess may predate the origin of terrestrial life. Some scientists have expressed reservations about the extraterrestrial origin of the amino acids previously investigated, but this examination reveals 15N values in the enantiomers in excess of those found in terrestrial enantiomers and confirm their indigenous origin. This research suggests that the enantiomeric excess, deemed to be a precursor for the development of life on earth, originated in an extraterrestrial source.
Publication Name: Nature
Subject: Zoology and wildlife conservation
ISSN: 0028-0836
Year: 1997
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Anomalous CH4 and NH4+ concentrations at an unsedimented mid-ocean-ridge hydrothermal system
Article Abstract:
The Endeavour segment of the Juan de Fuca Ridge contains CH4 and NH4+ concentrations greater than those measured previously at any unsedimented mid-ocean ridge. The decomposition of sub-sea-floor organic matter associated with sediments buried at an earlier stage of the ridges evolution causes these high CH4 and NH4+ concentrations in the hydrothermal environment.
Publication Name: Nature
Subject: Zoology and wildlife conservation
ISSN: 0028-0836
Year: 1993
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Upper-mantle dynamics revealed by helium isotope variations along the southeast Indian ridge
Article Abstract:
Research is presented concerning the quantitative relation of spatial variations in geophysical and geochemical specifications along 5,800 kilometers of the southeast Indian ridge through the study of helium isotope variations.
Publication Name: Nature
Subject: Zoology and wildlife conservation
ISSN: 0028-0836
Year: 2001
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