Space Topics: Planetary Analogs
The Antarctic Search for Meteorites
More Waiting; Runway's Ready; Ralph Goes Home
December 17-22, 2008
John Schutt paving the skiway
Credit: ANSMET |
Beardmore Glacier
Credit: ANSMET |
Paving the Way
December 17, 2008
If there are no technical hiccups, this will be the first post from the deep
field.
Although ANSMET has been working in Antarctica every year but one since
1976, every year has the potential to bring new surprises. This year was no
exception. For the first time, ANSMET is preparing its own snow skiway for
the airplane that will bring the team into the field. The reason for this
is complicated, but in essence, it was caused by problems with airplane scheduling
in Antarctica. ANSMET offered a solution: We would prepare a deep field skiway
for the Basler airplane to bring the main team out into the field.
The Basler is a plane built on the frame of the old DC-3 of legend. Basler
pilots do not want to land on very rough surfaces. In Antarctica in the deep
field, rough surfaces are the norm. The strong winds here sculpt snow into
hard drifts called Sastrugi. Sastrugi are so hard you can drive a snowmobile
over them with hardly a dent being made. (Quite the contrary, if you drive
a snowmobile over sastrugi too fast, you can break the suspension!) So something
had to be done to prepare our target site for the ANSMET team.
John Schutt and I were flown out on 11 Dec. with equipment to prepare a
snow skiway. Neither of us had done this before, but the task seemed simple
enough. We would drive up and down on a snowmobile dragging a heavy steel
grooming device. It would chew up the hard-pack snow with four “teeth” and
spread it out with a rake. Things were going smoothly (note clever pun) up
until a joint on the groomer broke. This was on 12 Dec. This brought work
to a screeching halt.
The solution is to get a replacement groomer flown out to us on a Twin Otter.
This seems simple enough. Just tell that to mother nature. After we put in
our call for the replacement, bad weather set in at McMurdo and then South
Pole. All Twin Otter flights were cancelled. For days.
John and
I are used to this waiting game. We haven’t been totally idle.
We have gone out and foot-searched areas near camp for meteorites, and have
found around twenty. We left them where they are, but marked them so we can
find them easily when the rest of the team arrives. The rest of the team will
bring the special collecting gear we use to harvest meteorites off the ice
without contaminating them.
The wait ended today. A Twin Otter arrived in the evening with the new groomer
and some other gear. We rapidly put the groomer together and are back at it
paving the skiway.
I call it Schutt Field.
In 1907, Ernest Shackleton (later Sir Ernest) was leading a team of explorers
to attempt to be the first to reach the South Pole. One hundred and one years
ago on this date, his team was ascending the Beardmore glacier on foot, pulling
sledges laden with hundreds of kilograms of gear. They were about 70 kilometers
(45 miles) north of where the ANSMET camp is located.
If you would like to learn more about Sir Shackleton’s heroic journey,
John and I recommend getting a copy of “The Heart of the Antarctic” by
Sir Ernest Shackleton. This book is Shackleton’s account of his attempt
to be the first to reach the South Pole.
Cheers,
duck
Birdwatching in McMurdo
Credit: ANSMET
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North for the winter
December 18, 2008
This little birdy is flying North later today. Since March
I had planned to spend only a short time in the field this season- about 10-12
days (in fact I wasn't sure I'd go to Antarctica at all because of family obligations
whose schedule I couldn't control). Knowing this, I made sure the 08-09 field
team was flush with veterans who could keep things going in my absence. And
although I have been here right up to the moment of field team deployment,
the delays that have built up (about 8-9 days) now make it silly for me to
go into the field, for a couple of reasons. First off, my exit from the field
(and Joe's entrance) was meant primarily as a resupply mission; an opportunity
to get a little more fuel, or stuff we have broken or lost 10-12 days into
the season. It makes little sense to have a resupply two days after we get
into the field, particularly since we will have had 5 flights over the past
week. Second, going out into the field simply to observe for a day or two is
a huge waste of resources during a field season where air logistics are so
strained that many projects are simply wrapping up and going home. For me to
waste a flight under those circumstances, when we're one of the LUCKY groups
actually getting to do our field work, would be a slap in the face of many.
I can't do that. Finally, simply staying in the field longer isn't an option
for me this year (see family obligations clause above).
So with 95% of my
job as Principal Investigator of ANSMET done (getting the field season underway),
and my replacement ready to go, I'm going to gracefully step out of the way.
The field season goes on, just without me. I won't deny that this feels very,
very wrong on a personal level; I really do live to hunt meteorites, and the
thrill I get being out on the plateau and finding rocks that have been untouched
since the birth of the solar system hasn't diminished at all. But it's the
right decision in every logical way. The hardest part of my job really is done;
the field team will end up with a better schedule of resupply missions, and
we can honestly say that our project made sacrifices to avoid wasting any logistics.
And of course I get one personal perk out of this; if the flight schedule allows
I should be home for Christmas with my family for only the 2nd time in the
last 10 years.
And if any of you have exceptional psychic abilities, please
send emanations to Qantas/American Airlines that will open up a few seats on
those chc-akl, akl-lax and lax-cle flights I'm trying to get on! Dec. 19 would
be nice.
-Ralph
Alphonse
"Alphonse" is the first meteorite found this year. It is about 2.5 cm (1 inch) across.
Credit: ANSMET
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Curly
"Curly" is possibly not a meteorite, but does not look like local Earth rocks either. It is about 4 cm (1.5 inches) across.
Credit: ANSMET
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Call me…Plow King
December 18, 2008
Today we got right at it. As soon as breakfast was done, John went out and
started grooming the skiway. After he got tired, I took over. So it went all
day until supper. We each put in several hours on the snowmobile during the
day, and we made great progress. I am sure the Basler pilots will compliment
us on such a fine, fine skiway.
We were aided by good weather. The wind speed is relatively low today, and
this helps us stay outside for long periods without suffering from the cold.
Indeed, I could have stayed out all day without trouble. John thinks we only
have about an hour’s worth of work left to do. We will be ready for a Basler landing
tomorrow. Hopefully, a flight can be arranged and the rest of the team can begin
to arrive.
In a previous post I mentioned that John and I had done some foot-searching
while we were waiting for the replacement groomer. When I was not busy plowing,
I went out and imaged a couple of the rocks we found. One is the first meteorite
discovered by the 2008-2009 ANSMET team. It will not get an official meteorite
name for several months; not until a preliminary examination is done by scientists
at NASA Johnson Space Center and the Smithsonian Institution. For the time
being, I’ll call it “Alphonse.”
Alphonse is typical of the meteorites we find. Many are about this size, they
are rounded, and often have a black glassy coating known as fusion crust. Fusion
crust develops on meteorites as they pass through the atmosphere. Friction
with the air molecules heats up the outer surface, melting it, and smoothing
any sharp points the rock may have had in space. When the meteorite slows down,
the melted coating freezes to a black glass, the fusion crust.
Sometimes we find rocks that we are not sure what they may be. We have found
one already. I will call this rock “Curly” after my favorite of the
Three Stooges. This is a black shiny rock. It is not like any other Earth rock
we have yet seen in the area, but it is also not like any meteorite John or I
remember seeing. We have marked it, and will wait for further information before
we decide whether to collect it or not.
One thing Curly could be is coal. There are coal seams in the Transantarctic
mountains. In fact, just north of here in the Queen Alexandra Range there is
coal. I was there with ANSMET in 1997-1998. My memory is that the coal does
not look exactly like Curly, but that was 11 years ago, and I an not sure.
After looking at Curly again today, I am beginning to think that it is coal.
While we are searching this year, we will keep our eyes open for other rocks
like Curly. If we decide Curly is definitely coal (or some other Earth rock),
we will leave it where it is. If at the end of the season we still cannot decide,
we will collect Curly. ANSMET prefers to collect a few atypical Earth rocks
rather than take the chance of leaving a new and unusual meteorite behind.
101 years ago on this date: After traversing the Ross ice shelf and the Beardmore
glacier, Shackleton’s expedition finally reached the Polar Plateau. They
man-hauled their sledges of gear and food up the slope, crossing difficult pressure
ridges and dangerous crevasses. They covered six and a third miles, but because
they could only take half their gear at a time, they actually walked nineteen
miles, climbing the slope up to the plateau pulling heavy sledges twice!
Cheers,
LYAN
duck
McMurdo from Ob Hill
Credit: ANSMET
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'round town
Credit: ANSMET
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We miss you, Ralph!
Credit: ANSMET
| Esperemos
December 19, 2008
Two full weeks have gone by since our arrival in McMurdo, and we inch ever closer
to getting into the field. The key word in that phrase is inch. Since NSF has
discouraged overuse of the LC-130s due to fuel costs, the Ken Borek Twin Otters
and Baslers are oversubscribed. Our field site is far enough away that we really
need the Basler, which is larger than the Twin Otters by maybe double, for our
three put-in loads of gear and passengers. But other groups need these planes
as well, so the pilots continue to put in long hours, and we continue to wait.
We're currently hopeful for a Monday (eek) put-in.
We each pass the time in our own special ways. We all meet for meals (although
breakfast has started to slip now that Ralph has gone home...) and usually finish
the evening together at the coffee house or another establishment. Last night
we were at Scott Base again for American night. This is a short, lovely jaunt
up the hill and two miles over, and though we suspect Joe walked home last night
for the nice views of Erebus, the ice shelf, and Ob Hill, the other three of
us took the lazy, shuttle mode. From here the plans vary widely - Joe probably
hits the sack first, followed by me, after an episode of Firefly or similar,
while Deon and Amy either watch more DVDs or go to Crary to work on LPSC abstracts
or the weblog until the wee hours. It's easy for this to happen, since there
are no bedtime cues from the sun! I believe we'll become fully nocturnal by next
week if we don't get into the field.
I took over Ralph's few remaining tasks in McMurdo to become transportation and
cargo mistress - a title I relish and abuse. Basically this involves walking
around to the different departments, checking on our flight status and location
of our cargo still waiting to go into the field. I find I'm becoming more and
more Ralph-ian all the time - I wander around town in my Carhartts, baseball
cap, and pager talking with people, checking the flight schedule, and raiding
the skua bins. It's scary. The flight ops girls have told me to just call from
now on, don't come by.
Here's hoping they run us out of town before we can do any more damage.
A few side notes: We appreciate Emily Lakdawalla's coverage of our blog on her
Planetary Society blog, we're glad she's helping to spread the word. So I guess
I just blogged her blog of our blog? It's a blog war! I'm sure there's some geek-speak
for that... Also, props to Barb, Nick, Dave, the Rads, and Troy for the mail
- many thanks!
And finally, our sympathies go to the family of Steve Ostro. He was a strong
proponent of research on small bodies in the solar system, so we feel he is an
ANSMET kindred spirit. He'd have loved coming down with us.
-- Jani Radebaugh
Picturesque pressure ridges
Credit: ANSMET
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Amy on the pressure ridge path with Scott Base in the background
Credit: ANSMET
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Seals near Hut Point
Credit: ANSMET
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The Waiting Game
December 22, 2008
We continue to wait in McMurdo to be deployed and as I write (knock on wood),
our first gear flight will go in on Monday. In the meantime, we’ve been
hanging around McMurdo fulfilling a role we’ve learned is termed a UE or “Useless
Eater”. We’ve been enjoying the recent weather in McMurdo, which
has been relatively warm and sunny. We just hope we don’t use up all the
good weather karma before our put-in flights next week!
Yesterday I took advantage of an unexpected opening and went along for a
tour of the pressure ridges near Scott Base. An arrangement has been worked
out with the Kiwis to allow several tours a week from McMurdo. Our group lucked
out with excellent weather and good lighting for pictures. The pressure ridges
are due to buckling and cracking where the sea ice meets the permanent ice
shelf. The result is amazing ice formations. The pictures don’t really do them justice.
Many had a beautiful deep sky blue color and their edges had sometimes been sculpted
into intricate patterns through the combined actions of wind, melting, and sublimation.
There were also several light blue pools of melt water to be seen along the path.
The pressure ridges were especially high this year, according to several trip
members who’ve seen them develop over the past few years. Seals sometimes
come up through the cracks in the ice associated with the pressure ridges, though
our tour did not happen upon any. Jani, Deon and I did however catch a few lazing
about near some cracks in the ice near Hut Point, on a different day’s
jaunt around McMurdo.
Cheers,
Amy
Status Update
December 22, 2008
A quick update on our schedule...Our
first cargo flight went out this morning (Monday). The weather looks good and
another flight is scheduled in 2 hrs. If all holds, the remaining 4 of our
team in McMurdo will put into the field early on Tuesday morning. Keep your
fingers crossed for us, because we are REALLY ready to go collect meteorites!
Last night we were invited for dinner at Scott base and asked to give a science
lecture. It went really well, and the Kiwi's were not only very interested
by our work, but were also a very interactive audience and we all had a very
enjoyable time. We were very jealous of the fireplace they have in their reading
room!
Aloha,
Deon.
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