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Carbonaceous chondrites as bioengineered comets
SPIE Proceedings, 2012The discovery of microfossils on carbonaceous meteorites has electrified the public with the first concrete evidence of extraterrestrial biology. But how these organisms colonized and grew on the parent body–the comet–remains a mystery. We report on several features of cyanobacteria that permit them to bioengineer comets, as well as a tantalizing ...
Robert B. Sheldon, Richard Hoover
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Organic Matter in Carbonaceous Chondrites
1986Carbonaceous chondrites are objects of great interest for chemists and astrophysicists. They contain a large number of abiogenic organic molecules and they are fragments of the least metamorphized bodies which exist in the solar system. Therefore, the study of carbonaceous chondrites affords information about the state of matter 4.5 Gyr ago.
Françoise Mullie, Jacques Reisse
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Boron in Carbonaceous Chondrites
Nature, 1968BORON is remarkable in that its compounds are common and inexpensive although the element occurs quite low on the cosmic abundance scale, alongside lithium and beryllium. The cosmic scarcity of these three light elements is related to the ease with which their nuclei are disintegrated during nucleogenesis, whereas the terrestrial familiarity of borates
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Shock metamorphism of carbonaceous chondrites
Geochimica et Cosmochimica Acta, 1992Shock effects were studied in 69 carbonaceous chondrites, including CM2, CO3, CV3, ungrouped C2-C4, and CK4-6 chondrites, using optical microscopy of thin sections. It is shown that the classification scheme of Stoeffler et al. (1991) for the progressive stages of shock metamorphism in ordinary chondrites is also applicable to carbonaceous chondrites ...
Edward R.D. Scott +2 more
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Space Science Reviews, 1963
The carbonaceous chondrites are a group of stony meteorites characterized by the presence of an appreciable amount of carbonaceous material other than free carbon (diamond and graphite). They have been divided into three subgroups known respectively as Type I, Type II, and Type III.
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The carbonaceous chondrites are a group of stony meteorites characterized by the presence of an appreciable amount of carbonaceous material other than free carbon (diamond and graphite). They have been divided into three subgroups known respectively as Type I, Type II, and Type III.
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Developing Carbonaceous Chondrite Asteroid Simulants
Earth and Space 2018, 2018This paper describes the processes and challenges of producing high-fidelity asteroid simulants. DSI (in partnership with UCF) is producing four families of carbonaceous chondrite simulants: CI, CR, CM, and C2. Britt provided target mineralogies, recommendations for researcher safety considerations, and target physical characteristics of selected ...
Covey, S. D. +3 more
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Fluorescent organic matter in carbonaceous chondrites
Advances in Space Research, 1999Fluorescent organic matter in carbonaceous chondrites was investigated using a microscope equipped with a fluorescence spectrophotometer. Fluorescent particles were observed in powdered CM2 carbonaceous chondrites (Y-74662, Y-7791198, and Murchison) without carbon enrichment by acid treatments. Although it was difficult to find fluorescent particles in
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Noble gases in carbonaceous chondrites
Geochimica et Cosmochimica Acta, 1970Carbonaceous chondrites noble gases measurement by mass spectroscopy, discussing compositional trends and ...
Emanuel Mazor +2 more
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Boron concentrations in carbonaceous chondrites
Geochimica et Cosmochimica Acta, 1978We have analyzed B in carbonaceous chondrites in order to clarify a factor of 100 difference between the solar system B abundance derived from the solar photosphere and that inferred from previous meteorite data. Consistent results were obtained from two instrumental methods for B analysis: (a) counting of the high energy betas from ^(12)B produced by ...
Weller, Martha Riherd +3 more
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Rhenium-Osmium Isotope Systematics of Carbonaceous Chondrites
Science, 1989Rhenium and osmium concentrations and Os isotopic compositions of eight carbonaceous chondrites, one LL3 ordinary chondrite, and two iron meteorites were determined by resonance ionization mass spectrometry. Iron meteorite 187 Re/ 186 Os and 187 Os/ 186
R J, Walker, J W, Morgan
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