Primitive Matter in Meteorites
نویسندگان
چکیده
منابع مشابه
Interstellar chemistry recorded in organic matter from primitive meteorites.
Organic matter in extraterrestrial materials has isotopic anomalies in hydrogen and nitrogen that suggest an origin in the presolar molecular cloud or perhaps in the protoplanetary disk. Interplanetary dust particles are generally regarded as the most primitive solar system matter available, in part because until recently they exhibited the most extreme isotope anomalies. However, we show that ...
متن کاملOrganic matter in meteorites.
Some primitive meteorites are carbon-rich objects containing a variety of organic molecules that constitute a valuable record of organic chemical evolution in the universe prior to the appearance of microorganisms. Families of compounds include hydrocarbons, alcohols, aldehydes, ketones, carboxylic acids, amino acids, amines, amides, heterocycles, phosphonic acids, sulfonic acids, sugar-related...
متن کاملInconclusive evidence for nonterrestrial isoleucine enantiomeric excesses in primitive meteorites.
Pizzarello et al. (1) recently described the soluble organic content of eight Antarctic Renazzo-type (CR) carbonaceous chondrites and reported large enantiomeric excesses (ee) of Lisoleucine and D-alloisoleucine. The reported values of ee decrease with inferred increases in aqueous alteration. We believe the conclusions presented in the paper are not fully justified and the data are potentially...
متن کاملLarge enantiomeric excesses in primitive meteorites and the diverse effects of water in cosmochemical evolution.
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...
متن کاملEvaluation of the 129I Half-Life Value Through Analyses of Primitive Meteorites
The preserved record of decay of now-extinct 129I into 129Xe forms the basis of the I-Xe chronometer. Comparison of the high precision I-Xe and Pb-Pb ages of chondrules and pure mineral phases separated from eight meteorites suggests the 17.5 ÷ 14.6 Ma range for the 129I half-life, assuming that the 235U and 238U half-lives are correct. The mean value of 16 Ma indicates that the 15.7 Ma half-li...
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ژورنال
عنوان ژورنال: Symposium - International Astronomical Union
سال: 1987
ISSN: 0074-1809
DOI: 10.1017/s0074180900154506