SETI bioastro: Scientists Seek Cold-Loving Microbes And Meteorites In Antarctica

From: Larry Klaes (lklaes@bbn.com)
Date: Wed May 03 2000 - 17:35:48 PDT


Date: Wed, 3 May 2000 21:25:55 GMT
From: Ron Baalke <BAALKE@kelvin.jpl.nasa.gov>
To: astro-l@uwwvax.uww.edu
Subject: Scientists Seek Cold-Loving Microbes And Meteorites In Antarctica

http://science.nasa.gov/headlines/y2000/ast03may_1m.htm

A Mid-summer's Microbe Hunt
NASA Science News

A team of explorers including astrobiologist Richard Hoover and astronauts
Jim Lovell and Owen Garriott traveled to Antarctica in January 2000 to
search for extreme-loving microbes.

May 3, 2000 -- Imagine going on summer vacation to a resort where the sun
never sets, the temperature never rises above -10 C, and all the sun
worshipers are short, well-insulated waterfowl. It may not sound like a
dream vacation, but to Richard Hoover, an astrobiologist at NASA's Marshall
Space Flight Center, it was just what the doctor ordered.

In January 2000, Hoover joined an eight-member team of explorers on an
expedition to search for exotic microbes in one of the harshest environments
on our planet - the frozen, windswept continent of Antarctica. It was all
part of Hoover's continuing research to find hardy microorganisms on Earth
that could be similar to life forms that might exist in places like Martian
permafrost and beneath the ice of Jupiter's moon Europa. The 18 day
expedition, conducted near the middle of Antarctica's summer when the sun
was above the horizon 24 hours a day, allowed Hoover and his colleagues to
collect a treasure trove of microbial and meteoritic samples for analysis at
the Marshall Space Flight Center.

"This research expedition called Antarctica 2000 was sponsored by the
Planetary Studies Foundation in Chicago", said Hoover "and it included a
search for meteorites as well as the search for microorganisms that inhabit
the snow, ice and frozen rocks."

The Antarctica 2000 team included Planetary Studies Foundation president
Paul Sipiera, Apollo 13 mission commander Jim Lovell, and astronaut Owen
Garriott. Other members of the Expedition were Dave Butts, Jim Pritzker,
Bill Gruber and Fox News journalist Amanda Onion and photographer Adam
Petlin. Sharon Hooper, a Chicago area junior high school science teacher,
beamed expedition reports and data back to her students in Rolling Meadows,
IL.

Antarctica, We Have a Problem...

Hunting for tiny microbes in a big place like Antarctica sounds like a
daunting task. Fortunately, thanks to Hoover's experience with cold-loving
extremophiles, the expedition knew just where to look. But first they had to
get there.

The group took off on January 5th, 2000 from Punta Arenas, Chile on a 7-hour
flight to the team's base station at Patriot Hills on the Antarctic
continent. The first attempt at landing there was aborted due to low clouds,
high winds and white-out conditions from blowing snow. This forced the
aircraft to turn back to Chile just before landing-and former astronaut Jim
Lovell took some good-natured teasing about uncompleted missions during the
return trip.

Finally, on January 9, clearing weather permitted a successful flight. They
landed on a slick wind-swept blue ice runway at Patriot Hills, Antarctica,
and the team settled in for two days of ice core sampling and collecting
melt-water specimens from small kettle ponds on local hilltops and from
water in bubbles trapped in the glacial ice.

Although they arrived in Antarctica during the continent's mildest season -
austral summer - the scientists had to endure extreme conditions by normal
workaday standards.

"Summer or not, it was a harsh work environment," says Hoover."Outdoor work
temperatures at Patriot Station ranged from -30 oC (-17 oF) to -10oC (14oF),
and even the interiors of the expedition's tents hovered at about -10oC. One
member of the team, Skylab astronaut Owen Garriott, suffered frostbite of
his toes while searching for meteorites on the ice fields."

A cold and windy workplace

On January 11th, the team flew a ski-equipped DC-3 aircraft to the blue ice
fields near the Moulton Escarpment in the Thiel Mountains, less than 300
miles from the South Pole. There they struggled to set up a tent camp at an
altitude of almost 8,000 ft. with temperatures ranging from -10oC to -35oC.
Despite wind gusts up to 60 mph that drove wind chill factors to -80oC, they
succeeded in setting up camp.

"We searched for meteorites five to six hours a day for three days." Hoover
related. "The strong Katabatic winds are hard to work in, but they were an
advantage for our research because they sweep the ice clear of snow and
reduce the ice depth through evaporation and sublimation. Meteorites
actually sit on the surface or are just below it."

The team collected 20 meteorites ranging from small marble-sized specimens
to a large 2 kg. sample. Hoover said, "None of the meteorites were touched
by human hands in order to avoid contamination and some were recovered
partially encased in ice."

"The microbial extremophiles in the Arctic and Antarctic glaciers and
permafrost represent analogues for microbes that may someday be found in the
permafrost or ice caps of Mars or on other icy bodies of the solar system,"
Hoover explains. "Ancient microbes can remain viable through
cryopreservation, becoming dormant and then resuming metabolic activity upon
thawing after being frozen in glacial ice or permafrost for thousands to
millions of years. These ancient cryopreserved microbiota may hold clues to
the origin and evolution of life on Earth and the distribution of life in
the cosmos."

To the South Pole

On January 16th, the team flew to South Pole Station to visit U.S personnel
stationed there and to gather more samples.

"We at the South Pole stayed for three days" Hoover said, "and we received a
very warm welcome in large part thanks to the presence of astronauts Owen
Garriott and Jim Lovell on the team, who gave interesting lectures at the
Amundsen-Scott Station. Jim Lovell's stories of Apollo 13 and other space
flights were especially welcomed. The South Pole was a much different
environment than the glacier ice and rocks we had been examining, with deep
snow covering the whole area. We took snow samples from outside the station
to study as part of our research."

Leaving the South Pole on Jan 18th, the expedition returned to Patriot Hills
for another week of microbe and meteorite hunting. While they were there,
Hoover reports that the team was able to gather some very special samples of
ice bubbles.

"These are bubbles in solid ice, sometimes in strings like a diver's air
bubbles," he says, "and in the summer, when the sun shines continuously a
liquid films form on the inside of the bubbles forming micro-edens where
microbes can grow."

They also gathered dark rocks trapped in the ice. These harbor 'cryoconite
communities'. Hoover noted that "cryoconite ecosystems in polar glacial ice
are very exciting. They afford clues to the types of microbes that might be
able to survive in water pockets that might exist on Mars or on other solar
system bodies."

The Antarctica 2000 team, along with their precious cargo of meteorites and
microbe samples, left the Patriot Hills on Jan. 27th, returning to Chile and
then on home to the U.S.



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