[meteorite-list] Gas in Rocks May Sustain Alien Life

From: Ron Baalke <baalke_at_meteoritecentral.com>
Date: Thu Apr 22 09:50:27 2004
Message-ID: <200204172120.OAA25196_at_zagami.jpl.nasa.gov>

http://dsc.discovery.com/news/briefs/20020415/mars.html

Gas in Rocks May Sustain Alien Life
Discovery News
April 16, 2002

April 16 - Huge colonies of Earth microbes are living off of hydrogen gas
released by common rocks, raising the possibility of similar life forms on
Mars, says a NASA researcher.

"The hydrogen comes from a subtle chemical reaction that occurs within rocks
that were once hot or even molten," said Friedemann Freund, a physicist,
geologist and chemist at NASA's Ames Research Center whose work appears in
the current issue of Astrobiology Journal.

Scientists have known for some time that hydrogen gas is produced when water
reaches freshly formed cracks in many types of rock. In 1995, researchers
discovered the first microbial ecosystem living off chemical energy in
basalt, a rock common to Earth and Mars.

But Freund found that rocks don't have to be cracked to release hydrogen.
Working with several types of rock in the lab, Freund analyzed released
gases and found that hydrogen is released throughout the entire rock as it
gradually cools over millions of years, resulting in vast quantities of
subterranean gas.

In fact, he said, the total mass of bacteria living below ground thriving
off hydrogen may be substantially larger than the mass of living things on
the planet's surface.

Freund's finding greatly expands the possibilities for life on Mars by
identifying a much more common process for the life-supporting gas.

"If deep microbial communities are to thrive over long periods of time, they
need a steady supply of hydrogen," he said.

Evidence is building that Mars once was, or still is, a planet with water,
making it possible that when that water comes into contact with rocks, it
forms hydrogen, as it does on Earth.

"The magmas that were flowing on Mars many years ago were saturated with
water vapor and it's a fact of life in our geological environment that when
you have water vapor in equilibrium with magma, you're going to have these
reactions."

David Kring, a planetary sciences professor with the University of Arizona,
said if Freund's work does indeed indicate a more common process for
hydrogen as chemical fuel for microbes, it will broaden scientists'
definition of "extreme" environments for life.

"Life that we now view as being extreme may not be extreme at all. It may be
very common, an ordinary niche that we simply weren't aware of in the past,"
said Kring.

"We are devising new technologies to locate and identify microscopic
organisms and the chemical processes they use to stay alive. In the context
of Mars, the research points to potential pockets where life may exist."
Received on Wed 17 Apr 2002 05:20:49 PM PDT