[meteorite-list] Meteorite Hunting in Antarctica

From: Ron Baalke <baalke_at_meteoritecentral.com>
Date: Mon, 22 Jan 2007 12:25:46 -0800 (PST)
Message-ID: <200701222025.MAA28622_at_zagami.jpl.nasa.gov>

http://www.jhu.edu/~gazette/2007/22jan07/22meteor.html

Meteorite Hunting in Antarctica

APL staffers brave the elements to gather space rocks for researchers

By Hayley Brown
Applied Physics Laboratory
The JHU Gazette
January 22, 2007 | Vol. 35 No. 18

Some APL staffers will go to the ends of the Earth and back in the
name of science. Take, for example, Nancy Chabot, Ben Bussey, Cari C
orrigan and Andrew Dombard, all of whom have spent time in Antarctica
collecting meteorites as part of the Antarctic Search for Meteorites
program, known as ANSMET.

ANSMET, which is funded by the National Science Foundation's Office of
Polar Programs and NASA, aims to find and characterize meteorite samples
in Antarctica and make those samples available to researchers worldwide.
Since its inception in 1976, ANSMET has provided the scientific
community with more than 15,000 meteorite specimens. These samples are a
unique way to study outer space without actually leaving the planet, and
they can offer important clues about the formation of the solar system
and the compositions and histories of asteroids and other planetary bodies.

Antarctica is uncommonly fertile ground for meteorite hunting; about 85
percent of all meteorites recovered worldwide are found there. In some
areas, the Antarctic ice sheet, nearly two miles thick, effectively
buries the continent and allows little to no accumulation of indigenous
sediment, which means that any rocks found on the surface are likely
extraterrestrial. They are easy to spot because they contrast starkly
with the homogeneously icy landscape.

Antarctica's ice flow acts as a natural concentration mechanism. As the
ice sheet creeps across the continent, it occasionally bumps into
mountain ranges and other obstructions beneath the ice. When strong
winds strike such areas, they remove large accumulations of snow and
ice, exposing clusters of meteorites on the surface.

Individual ANSMET missions last eight weeks - six spent looking for
meteorites, with a week at either end for preparation and cleanup.

The journey to Antarctica begins in New Zealand, where travelers
assemble their gear, and the flight out of this subtropical paradise can
be as treacherous as Antarctica itself, attests Dombard, a scientist in
the Space Department's Planetary Exploration Group.

"We were packed in like sardines for seven hours, and it was very
noisy," he said. "It's especially uncomfortable if the weather is bad.
When I went, it took us four tries to get down there, with Antarctic
weather canceling the flight or forcing the plane to turn back to New
Zealand after making it halfway."

The sojourn in Antarctica has its own hazards. That's why researchers
participate in a two-day survival school, learning how to cope with the
inhospitable climate and how to execute a rescue if something goes wrong.

Chabot, also a scientist in the Planetary Exploration Group, has visited
Antarctica five times.

"We would wake up, eat breakfast in the tent, dress warm and get
prepared for the day, with plenty of sunscreen - the sun is up 24 hours
a day in the summer season," she said about the start of a typical day.
Then each member of the team would get on a snowmobile and travel to the
ice field to search for meteorites. This usually involved driving up and
down in systematic grids to cover the ice area, stopping whenever they
found a meteorite.

"Some days were slow," Chabot said, "and we'd find less than 10
meteorites. But other days, we collected more than 100 in one day."

Lunch usually consisted of beef sticks and beef jerky and lots of
chocolate. The team would get back to camp before 6 p.m., fuel the
snowmobiles, catalog and record the meteorites of the day, melt ice for
water, cook dinner and read a book or play a game before trying to get a
good night's sleep. "Being out in the cold constantly takes a lot out of
you, and you need lots of sleep," Chabot said. Temperatures were
generally 14 to minus-4 degrees Fahrenheit, without wind chill
considerations.

Even with the inherent hazards and obstacles, the scientists say the
trip is worth the risks. "It's such a unique opportunity," Chabot said.
"You deal with being cold, being dirty and other hardships. But when you
go outside and look around, it's so beautiful, it just puts everything
else into perspective."

This article first appeared in The APL News. Its writer, Haley Brown,
served as an intern in APL's Office of Communications and Public Affairs.
Received on Mon 22 Jan 2007 03:25:46 PM PST