Cometa 67P/Churyumov-Gerasimenko contém ingredientes necessários para a origem da vida

sábado, maio 28, 2016

Prebiotic chemicals—amino acid and phosphorus—in the coma of comet 67P/Churyumov-Gerasimenko

Kathrin Altwegg1,2,*, Hans Balsiger1, Akiva Bar-Nun3, Jean-Jacques Berthelier4, Andre Bieler1,5, Peter Bochsler1, Christelle Briois6, Ursina Calmonte1, Michael R. Combi5, Hervé Cottin7, Johan De Keyser8, Frederik Dhooghe8, Bjorn Fiethe9, Stephen A. Fuselier10, Sébastien Gasc1, Tamas I. Gombosi5, Kenneth C. Hansen5, Myrtha Haessig1,10, Annette Jäckel1, Ernest Kopp1, Axel Korth11, Lena Le Roy2, Urs Mall11, Bernard Marty12, Olivier Mousis13, Tobias Owen14, Henri Rème15,16, Martin Rubin1, Thierry Sémon1, Chia-Yu Tzou1, James Hunter Waite10 and Peter Wurz1

+ Author Affiliations

↵*Corresponding author. Email: kathrin.altwegg@space.unibe.ch

Science Advances 27 May 2016:

Vol. 2, no. 5, e1600285




Abstract

The importance of comets for the origin of life on Earth has been advocated for many decades. Amino acids are key ingredients in chemistry, leading to life as we know it. Many primitive meteorites contain amino acids, and it is generally believed that these are formed by aqueous alterations. In the collector aerogel and foil samples of the Stardust mission after the flyby at comet Wild 2, the simplest form of amino acids, glycine, has been found together with precursor molecules methylamine and ethylamine. Because of contamination issues of the samples, a cometary origin was deduced from the 13C isotopic signature. We report the presence of volatile glycine accompanied by methylamine and ethylamine in the coma of 67P/Churyumov-Gerasimenko measured by the ROSINA (Rosetta Orbiter Spectrometer for Ion and Neutral Analysis) mass spectrometer, confirming the Stardust results. Together with the detection of phosphorus and a multitude of organic molecules, this result demonstrates that comets could have played a crucial role in the emergence of life on Earth.

Keywords Origins of life chemistry astronomy comets prebiotic molecules amino acid 67P/Churyumov-Gerasimenko

Copyright © 2016, The Authors

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