The research could bolster those who think meteors and comets provided vital ingredients for life on Earth A meteorite found in Antarctica could lend weight to the argument that life on Earth was aided by an extraterrestrial body, scientists claim.
Chemical analysis of the meteorite shows it to be rich in the gas ammonia, which contains the element nitrogen - found in the amino and nucleic acids which form the basis of life.
Analysis of other meteorites has revealed organic compounds which the authors of the new paper believe are too complex to have played a role.
Professor Sandra Pizzarello Arizona State University“Meteorites could have showered the Earth with an attractive mix of components, including a large amount of ammonia”
Details of the study by researchers at Arizona State University and the University of California, Santa Cruz, are published in the journal Proceedings of the National Academy of Sciences.
The new study is based on analysis of just under 4g of powder extracted from a meteorite called Grave Nunataks 95229 (named after its place of discovery in Antarctica).
The meteorite was found in 1995 and belongs to the "Renazzo" family of "carbonaceous chondrite" meteorites, a group of meteorites that retain much of their original composition and have not been melted by their parent body. They can contain high proportions of water and organic compounds.
The powder sample was shown to contain abundant amounts of ammonia as well as hydrocarbons (including the amino acids glycine and alanine).
Analysis of the isotopes of nitrogen and hydrogen found within the sample suggest the material originated from a "cold cosmic" environment, and were not the result of Earthly contaminants.
The meteorite GRA95229 from which a sample was taken and analysed for this latest study Professor Sandra Pizzarello, who led the research, says the study "shows that there are asteroids out there that when fragmented and become meteorites, could have showered the Earth with an attractive mix of components, including a large amount of ammonia".
She claims the meteorite provides better evidence of the possible "prebiotic" role played by meteorites than the "Murchison" group of carbonaceous chondrites.
The professor says the Murchison meteorites represent "too much of a good thing" and contain hydrocarbon molecules which you would expect to find at the end rather than the start of the life story.
She believes t
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