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OverviewIt is proposed that the AIB amino acids at the K/T boundary were synthesized during entry of a comet. However, whether they were synthesized or supplied directly from space, the concentration of amino acids in the shallow K/T sea would have been about 10(exp -7) M. It is probable that clays were the dominant sinks for the amino acids in the K/T sea and in the primordial ocean. Because clay removed amino from the sea so quickly, we must study the amino acid contribution from individual comets in order to evaluate the effectiveness of comets for chemical evolution. Such an evaluation shows that comets would have produced amino acid concentrations higher than equilibrium concentrations of amino acids from corona discharge at all times preceding the age of the oldest fossils. The preferred sites for chemical evolution of cometary amino acids are in cloud drops and tide pools where the concentration of amino acids would have been the highest. Life could have originated at the surface even during periods of intense bombardment of the earth before 3.8 billion years ago. Aggarwal, Hans R. Unspecified Center NCC2-722... Full Product DetailsAuthor: National Aeronaut Administration (Nasa)Publisher: Createspace Independent Publishing Platform Imprint: Createspace Independent Publishing Platform Dimensions: Width: 21.60cm , Height: 0.20cm , Length: 27.90cm Weight: 0.100kg ISBN: 9781722292089ISBN 10: 1722292083 Pages: 32 Publication Date: 04 July 2018 Audience: General/trade , General Format: Paperback Publisher's Status: Active Availability: Available To Order We have confirmation that this item is in stock with the supplier. It will be ordered in for you and dispatched immediately. Table of ContentsReviewsAuthor InformationTab Content 6Author Website:Countries AvailableAll regions |
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