[meteorite-list] Ice Diary 4: The Hunt Begins

From: Ron Baalke <baalke_at_meteoritecentral.com>
Date: Thu Apr 22 10:23:48 2004
Message-ID: <200303131817.KAA24499_at_zagami.jpl.nasa.gov>

http://www.astrobio.net/news/modules.php?op=modload&name=News&file=article&sid=400&mode=thread&order=0&thold=0

Ice Diary 4: The Hunt Begins
Astrobiology Magazine
March 13, 2003

Summary: The Ice Diary series explores the adventures of
a dedicated group of meteor hunters. The National Science
Foundation, NASA and the Smithsonian collect and curate
extraterrestrial samples scoured from the South Pole. This
week's chroniclers get whipped by the Kabatics: the cold
air that sinks over Antarctic continent, and head toward
the ocean with no landscape of note to slow it down.
"Despite our technology, we are in the same elements that
stranded [early explorers]".

Ice Diary 4
The Hunt Begins


8 December, 2002

We finally made it to our field camp! An LC-130 operated by the New York Air
National Guard dropped us off at the Beardmore South Camp a couple of days ago. The
next day we took our gear and snowmobiles on a 5.5-hour traverse to our camp at
Goodwin Nunatak, on the boundary of the Polar Plateau and the Trans-Antarctic
Mountains.

Antarctic ice backs up against the mountains, flows upward, and is
ablated by the wind. Meteorites are revealed in these "blue ice" areas,
but meteorites are not the only rocks. Some of the blue ice contains
moraines --a deposit of local rocks from a variety of areas. Some of the
local rock is dark and rounded like the meteorites, so close observations
are necessary. We've discovered that meteorites tend to collect with
other rocks in the wind scoops that formed around boulders.

The blue ice looks like a frozen ocean. The wind carves the ice into smaller waves
called "sastrugi" that almost look like whitecaps on the swell. In other areas the ice is
almost flat.

Our meteorite searching was extremely successful today. Although we weren't doing
any systematic searching, we still found 23 meteorites to add to the 21 we found
yesterday. We had most of our success at a place unofficially named Scoraine Moraine,
after Robbie Score, a former ANSMET team member. I hope we get a chance to go
back. It was late in the day and I think we left a lot behind.

I can't explain the thrill at finding a meteorite. Danny compares this to an Easter Egg
hunt, but I think it is more like fishing. Sometimes you can't catch them fast enough,
and other times you go for hours without finding any. It's great to find several, but
finding a rare variety is just as rewarding.


9 December, 2002

No searching took place today, and none was planned. If it had been a search day, it
would have been miserable. It started getting windy overnight, and the temperature
dropped to -14F. The wind has been gusting 10 to 20 knots all day and the high was
about -5F. We figured the wind-chill was about -45F.

We thought we were ready for the wind, but drifts formed in areas we didn't expect and
buried some of the equipment. We had to dig out the ski-doos and shovel additional
snow around the base of the tents to insulate them. Everything is more difficult in the
wind and cold. Just chipping ice for melt water or refueling stoves can be a challenge.

Carlton Allen arrived by twin otter plane today. Twin otters can land in strong winds,
on short runways, and snowy surfaces. He brought us peanut butter bars from the
McMurdo galley. Jaime explained before we left how important good food is to the
morale of the team. He's an amazing cook and seems to enjoy it. We've already had
sausages, steaks, stroganoff, and a variety of sides. Tonight, Jaime and I ate over at
Danny and Dante's tent and had shrimp fajitas. I stuffed myself because they were so
good. It's going to be hard to camp in the future without thinking of Jaime's cooking.

Jaime went up in the twin otter to scout out our upcoming traverse to McAlpine hills.
He also transferred ski-doo fuel to this camp and our camp at McAlpine. In addition to
all this, he constructed a wind turbine to provide electrical power. He is arguably the
busiest guy in camp. When Jaime returned, John boarded the twin otter and left for
South Pole. The reconnaissance team will join him tomorrow.


10 December, 2002

The winds picked up again last night, and Nancy came by this morning to tell us that
we were going to have a "weather delay." This meant a day in the tents and no
meteorite searching. Just looking outside, you couldn't tell how harsh the conditions
were. The sky was blue, but the horizon was hazy from all the blowing snow. We were
experiencing the full onslaught of the Katabatics.

Katabatic winds are pressure-derived winds. Cold air sinks over the
Antarctic continent and races over the ice toward the ocean. There is nothing
to stop the wind and the mountains only funnel it. We can tell when the
Katabatics are coming from the pressure change. I have a barometer on my watch
that shows basic trends in barometric pressure. If we see a change toward high
pressure, that generally means that windy days are ahead.

My watch uses this pressure to estimate our altitude, but this doesn't work so well in
Antarctica. Due to the Earth's rotation, the atmosphere bulges a little at the equator
and thins at the poles. For instance, McMurdo is at sea level, but our "pressure
altitude" was about 1,500 feet above sea level. The effect is most pronounced at the
South Pole, which is already at an elevation about 9,000 feet above sea level. Due to
the effect of pressure altitude, it actually feels like it's over 11,000 feet! Members of
our Rekki team are concerned about this because it's easy to become winded and feel
ill at high altitudes. Plus they have been at McMurdo for a couple of weeks, which isn't
helping with their acclimation. Our camp is just below 8,000 feet but feels like its over
9,000 feet, which is equivalent to some of the higher mountain towns back home in
Colorado.

Jamie put it best yesterday when he said, "Things develop a life of their own down
here." This has been very true. First of all, batteries go dead overnight from the cold.
So, constant electrical power is necessary to run our satellite phone, computers,
cameras, and any other electronic device. We are turning both to solar and wind
generated power. We have been able to partially capture the wind to derive electrical
power through a wind turbine, but like most of our technology, it has been much more
complex than it sounds. Both systems ideally charge a bank of car batteries, off of
which the direct current is converted to an alternating current. Unfortunately these
items don't work perfectly and are entirely dependent on the weather.

To add to our technology limitations, our camp stoves have been breaking down at an
alarming pace. We have already gone through six of thirteen stoves that are supposed
to last us the whole six weeks. We depend on these stoves not only for cooking, but
also for heat in the tent. Hopefully, we will receive an emergency shipment of them
from McMurdo tomorrow.

Danny was in earlier and is reading about Shackelton's expedition and we were
comparing and contrasting our situation. Despite our technology, we are in the same
elements that stranded the crew of the Endurance. It's really a miracle that we can
post this to the web at all.

Despite our technology limitations, we are able to get news of the outside world
through a short wave radio that picks up stations from Australia. Carl Allen, who just
arrived yesterday, also brought news and a poem written by Dr. Ralph Harvey, the
principal investigator of the ANSMET team. Ralph usually makes it to Antarctica, but
is home in Cleveland this year with his newborn son. This poem was Ralph's reaction
to the images of the Rekki team spelling out ANSMET:

RAW! RAW! RAWS! THE METEORITES COME FROM MAWS! WE'LL PICK
THEM UP AND WRAP THEM UP ALL DAY AND NEVER PAWS!

WE'LL SNAG EM! WE'LL BAG EM! WE'LL DO A LITTLE DANCE!

AND IF IT IS A MARTIAN, WE'RE GONNA WET OUR PANCE!


11 December, 2002

Today we were rewarded with clear skies, calm winds, and mild temperatures (5 to
20F). It looked like it was still blowing pretty well up at Goodwin Nunatak, though, so
we went back to Scoraine Moraine for our systematic searching.

We picked up three meteorites on the way to Scoraine Moraine and
used this as an opportunity to bring Carl up to speed on the
collection procedure. We were all excited to get to Scoraine Moraine
because of our earlier success, but for the first hour, we found nothing.

Then Dante brought out his metal detector. We were all skeptical about
how well it would work with the low metallic
content of most meteorites. But when it found a meteorite buried in the snow and
another under a rock, we were all convinced. There was a tie today for meteorites found
by the metal detector versus those found by people.

The metal detector helped, but it was easy to become complacent and just follow it
around. Our most exciting meteorite find of the day came at the end on our way back to
camp. We think it might be an achondrite, a rare type of meteorite that is thought to
come from the asteroid 4 Vesta. We tried the metal detector on it and it gave no signal.

A twin otter plane made a couple of stops at our camp today to drop off replacement
stoves and brought in an expert on solar power to check out our solar array. Jamie
already had it working fine, but the technician brought us a new wind generator that
should be more productive than the last.


12 December, 2002

This morning started out calm and downright warm. It's funny how quickly 25 degrees
F feels like a warm day. This reminds me of the college students at Western State
University in Gunnison, CO, who play volleyball in t-shirts and shorts when the
temperature rises above 20 degrees F. By the time we reached Goodwin Nunatak,
however, the temperature had dropped to -2 degrees F and the wind was blowing.

Prior to today, we would just fan out and randomly search areas that had already been
searched in previous years. Today we lined up our ski-doos at equal distances apart
and drove in relatively straight lines looking for meteorites in our lanes. This sounds a
lot easier than it is. It seems like every time I looked up I had drifted closer to Danny
or farther from Linda. It almost took more concentration to stay in formation than to
watch for meteorites.

I've tried this kind of searching before with the Denver Museum Meteorite Recovery
Team. We hiked a short grass prairie in eastern Colorado looking for meteorites and
wound up drifting and crisscrossing each other's paths. One member of the team tested
our ability to pick out a meteorite from the field by tossing a Snickers bar in the middle
of our search. The Snickers was never recovered.

Despite our difficulty with staying in formation, we managed to recover 32 meteorites.
That brings our total up to 91 in just four days of searching. We finished Goodwin
Nunatak today, and will begin packing up camp tomorrow for our traverse to MacAlpine
Hills.

-----------------------------------------------------------------------------

Since 1976, the Antarctic Search for Meteorites program
(ANSMET), funded by the Office of Polar Programs of the National
Science Foundation, has recovered more than 10,000 specimens
from meteorite stranding surfaces along the Transantarctic
Mountains. Dr. Ralph Harvey and John Schutt are members of each
field party, serving as ANSMET continues to be one of the few
Antarctic research projects that invites graduate students and
senior researchers from other institutions to participate in our field
work on a volunteer basis--including the Teacher Experiencing
Antarctica (TEA) program. As a multi-agency collaboration, the
NSF supports field operations, NASA supports storage curation, distribution and
notification of recovered samples, and the Smithsonian provides long term curation
facilities for the collection and assist in sample characterization.

In this multi-part Ice Diary series, all commentary are atributed to Andy Caldwell
unless otherwise noted, and reprinted by permission as part of his participation in the
TEA program.
Received on Thu 13 Mar 2003 01:17:34 PM PST