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Evidence for Past Life on Early Mars: How the Evidence Stands

Published online by Cambridge University Press:  19 September 2017

Everett K. Gibson
Affiliation:
Astromaterials Research Office, NASA Johnson Space Center, Mail Code SR, Houston, Texas 77058, USA
Kathie L. Thomas-Keprta
Affiliation:
Lockheed Martin Space Operations, Mail Code C-23, Houston, Texas 77058, USA
Simon J. Clemett
Affiliation:
Lockheed Martin Space Operations, Mail Code C-23, Houston, Texas 77058, USA
David S. Mckay
Affiliation:
Astromaterials Research Office, NASA Johnson Space Center, Mail Code SR, Houston, Texas 77058, USA
Christopher Romanek
Affiliation:
Savannah River Ecology Laboratory, Drawer E, University of Georgia, Aiken SC 29802, USA
Susan J. Wentworth
Affiliation:
Lockheed Martin Space Operations, Mail Code C-23, Houston, Texas 77058, USA

Abstract

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Martian Meteorite ALH84001 contains four unusual features which have been interpreted as possible signatures of relic biogenic activity. After six years of intense study by the world's scientific community, the current status of the biogenic hypothesis is reviewed and shown to still be valid. Furthermore additional features have been observed in two younger Martian meteorites. The strongest argument for possible evidence of biogenic activity within the ALH84001 meteorite is the presence of truncated hexa-octahedral magnetite crystals which are only known on Earth to be the products of biology.

Type
Planetary Science
Copyright
Copyright © Astronomical Society of the Pacific 2004 

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