NASA Logo

NTRS

NTRS - NASA Technical Reports Server

Back to Results
Hydrothermal systems as environments for the emergence of lifeAnalysis of the chemical disequilibrium provided by the mixing of hydrothermal fluids and seawater in present-day systems indicates that organic synthesis from CO2 or carbonic acid is thermodynamically favoured in the conditions in which hyperthermophilic microorganisms are known to live. These organisms lower the Gibbs free energy of the chemical mixture by synthesizing many of the components of their cells. Primary productivity is enormous in hydrothermal systems because it depends only on catalysis of thermodynamically favourable, exergonic reactions. It follows that hydrothermal systems may be the most favourable environments for life on Earth. This fact makes hydrothermal systems logical candidates for the location of the emergence of life, a speculation that is supported by genetic evidence that modern hyperthermophilic organisms are closer to a common ancestor than any other forms of life. The presence of hydrothermal systems on the early Earth would correspond to the presence of liquid water. Evidence that hydrothermal systems existed early in the history of Mars raises the possibility that life may have emerged on Mars as well. Redox reactions between water and rock establish the potential for organic synthesis in and around hydrothermal systems. Therefore, the single most important parameter for modelling the geochemical emergence of life on the early Earth or Mars is the composition of the rock which hosts the hydrothermal system.
Document ID
20040173291
Acquisition Source
Legacy CDMS
Document Type
Reprint (Version printed in journal)
Authors
Shock, E. L.
(Washington University St Louis, MO 63130, United States)
Date Acquired
August 22, 2013
Publication Date
January 1, 1996
Publication Information
Publication: Ciba Foundation symposium
Volume: 202
ISSN: 0300-5208
Subject Category
Exobiology
Distribution Limits
Public
Copyright
Other
Keywords
Non-NASA Center
Review, Tutorial
NASA Discipline Exobiology
Review

Available Downloads

There are no available downloads for this record.
No Preview Available