Ice Diary Encore: Thawing Out

Ice Diary Encore

Thawing Out

Andy Caldwell, a science teacher at Douglas County High School in Castle Rock, Colorado, joined the Teachers Experience Antarctica (TEA) program and accompanied members of the Antarctic Search for Meteorites program (ANSMET) last winter.

"Part of my philosophy of teaching is to show students that science is an adventure," says Caldwell. "Aside from visiting another planet, I can’t think of a much larger adventure than traveling to Antarctica."

Caldwell and his fellow explorers arrived ready to seek out meteorites amid the snow and ice fields of Antarctica’s vast wilderness. From the permanent base in McMurdo, the team flew to the ancient Beardmore Glacier. They then traveled by snowmobile 60 kilometers south to the Goodwin Nunataks. After a week of meteorite discoveries, they traversed to MacAlpine Hills. There they hit the "mother lode," recovering more than 100 meteorites in a single day.

Fresh from his season in Antarctica, Andy Caldwell answers questions about his experiences in the field and his goals for the future.

Q: What did you miss the most about modern life while you were living in Antarctica?

In all honesty, we missed very little from modern life. Of course we had conversations about missing showers, pizza, and other "beverages," but for the most part we had a number of fairly modern conveniences. We had a satellite telephone, that, although expensive, allowed us to call home on occasion. We had an HF radio that allowed us to communicate with McMurdo station. We brought DVDs that we played on computers on bad weather days, plus games (both card games and video). I did occasionally have dreams that I was driving my truck. I wasn’t going anyplace specific, just driving.

Q: Was there anything that you thought you’d have a hard time living without, but when the time came, you found it wasn’t necessary?

Scott’s hut at Cape Evans with glacier in the background. Each year, more than 800 scientists from all over the world journey to this world of ice to conduct all types of research.

This is kind of pathetic, but I’m a die-hard Denver Broncos fan. I couldn’t imagine leaving in the middle of the season. I caught a couple of games on Armed Forces Television at McMurdo, and got highlights from one of the other scientists who called home every Monday to see what happened around the league. By the end of the field season, though, I completely forgot that they played.

Q: What was the most thrilling moment of the expedition?

It’s hard to single out one. It was great finding each meteorite, seeing the steam rising from Mt. Erebus, the world’s southernmost active volcano, or walking through the hut constructed by Captain Robert F. Scott at Cape Evans. But I think my favorite moments came when we climbed the small peaks in the Trans-Antarctic Mountains. We were probably the first people to reach the summit and the first to see the vistas from the peaks. In Colorado, you’re lucky if you’re the first one up that day! It was like being on another planet and being the first to experience it.

Q: Were you ever frightened?

Overall, I had complete confidence in our mountaineer and the Air National Guard servicemen who deployed us in the field. But there was a hairy moment on our last traverse. I was following our mountaineer, Jamie Pierce, in single file as we made our way across the Beardmore Glacier back to the camp where the LC-130 was scheduled to pick us up. I saw the snow collapsing in small pits behind Jamie’s ski-doo and realized we were in a crevasse field. Although we were careful about steering around most of the crevasses, we couldn’t spot every one. It’s kind of like a minefield. There were definitely moments I was worried about plunging into one.

Search field. The numbers refer to the numbers of meteorites found on different blue ice fields or in moraines. Red numbers indicate areas that have been completely systematically searched. Blue numbers indicate areas where we have found meteorites but have yet to finish searching the area. Some blue ice, such as that in the lower portion of the image, we still have to visit. The image is oriented with north at the top of the image, and the image is about 10 km wide.
Credit: Caldwell, TEA

Q: The Antarctic Meteorite Newsletter says that the final tally for your group was 607 meteorites – will you be kept apprised of the scientific findings regarding these rocks?

I hope so. The meteorites just arrived recently at the Johnson Space Center. They will take the next few months to check them out. They will start with the ones we labeled in the field notes as "interesting." After that, the meteorites are sent to the Smithsonian for final analysis. This usually takes a couple of years. At that time, a newsletter is sent to all meteorite scientists describing each one, in case they would like to request a sample or thin section for analysis. It could be years until we find if any of them were significant.

Q: Do you have any valued "souvenirs" from your Antarctic experience?

We were not allowed to keep any of the meteorites for ourselves. And that’s OK, because you never know if that one will hold clues to the origin of the Solar System or the origins of life. I did bring back t-shirts, hats– the usual from McMurdo. But my photographs are my best souvenirs. I was relieved when I got my film developed. This is kind of sappy, but the friendships I made with my teammates will last a lifetime.

Q: What were the first things you did after you got back from Antarctica?

I had a few days in New Zealand, so I got a haircut and beard trim right away. When I got home, I couldn’t wait to visit a restaurant known for its ribs. I had to jump back into teaching almost right away, so on the way home, I prepared a PowerPoint presentation on Antarctica for my students. This gave me a chance to get my lesson plans together and get the students fired up for the semester.

Q: Has your experience in Antarctica changed your outlook or perceptions in any way?

Absolutely, but it’s really hard to put into words. There’s a phrase down there, "Everybody needs a little Antarctica." I think I feel a little more humbled than before. A local newspaper misquoted me recently saying that I said, "(after this experience) I can do anything!" I don’t feel that way at all. In fact, for the first time in my life, I don’t feel I have to top this experience. I like to climb Colorado’s mountains and go backpacking in the wilderness. But now I want to do these activities for the experience, not to climb higher than before or hike further than before.

Q: What are your plans for the future? Would you go back to Antarctica for another meteorite-hunting expedition?

In the near future, I want to do a lot with my students. I have them involved with a project sponsored by the Denver Museum of Nature and Science called the All Sky Camera Network. This is a group of a dozen schools around Colorado that have digital cameras trained on a curved mirror that are trying to spot bolide events. When linked and triangulated, we hope to trace these events and recover the meteorites if any make it to the ground. We have caught several this year and hope to do field searches this summer. It’s great to get students involved in this type of authentic research.

As far as going back to Antarctica, I would love to, of course. However, the competition is fierce to become an ANSMET member. I didn’t realize this until recently when I attended the Lunar and Planetary Conference and saw how many qualified scientists wanted to go. The TEA program that sent me is a one time only deal. TEA is sponsored by the National Science Foundation, and they paid all my expenses so that I wasn’t a burden on my research team. If I went again, ANSMET would have to cover the costs of a substitute for my classes, plus any other fees. ANSMET is planning on taking someone from the Artists and Writers program in the future.

An astronaut on our team is trying to convince me to apply to NASA’s Educator Astronaut program. While I’m honored that she thinks I’m qualified, I need some time to think about it. I’d like to spend some time with my students and try to be a better teacher here.

What’s Next

Linda Welzenbach, one of the ANSMET team members, described in an Ice Diary entry what happens to the meteorites once they arrive at Johnson Space Center (JSC):

[The meteorites are kept in cabinets that are] filled with Nitrogen gas, which is used to dry out any ice or snow that adhered to the meteorites when they were collected.

Suitland, Maryland handling facility for meteor storage, Smithsonian
Credit: Chip Clark

The gas also keeps out moisture, salts, metals, and organic compounds for as long as the meteorites remain stored in that environment. After they’ve been thawed and dried, they are weighed, described, photographed, and given a name.

After NASA has cataloged the meteorite, they remove a few grams and send it to me at the Smithsonian for identification and description. I conduct a macroscopic investigation of the chips, separating out the unique chondrites, achondrites, and irons for in-depth analyses, while the rest of the ordinary chondrites are set aside to be classified using standard optical mineralogy methods.

[The meteorite samples we select for in-depth analyses] go to our Polished Thin Section preparer, who will take the chip, impregnate it with epoxy, glue it to an inch-round glass slide, cut off most of the sample, and grind the remainder down to the a thickness of 30 to 40 microns. At this thickness you can see through the rock. When placed under a microscope, you see a kaleidoscopic view of all of the individual minerals. Using an Electron Microprobe, you can find out the chemical make-up of the individual mineral crystals.

For the ordinary chondrites, we remove a small piece from the chip for classification using a petrographic microscope. We grind the tiny sample into a powder (tiny mineral crystals) and immerse them in special optical oils on a glass slide. Our observation of optical effects that occur between the crystal and the oil tell us something about the iron content of the mineral.

When all the meteorites are classified, we send the data back to JSC, where it will be published in the Antarctic Meteorite Newsletter. Scientists all over the globe will read it to find out about the new meteorite samples available for research. NASA handles the scientist’s requests for samples: there are up to 75 per year for an average of 600 samples. In the 26 years the program has been operating, over 300 investigators from 24 nations have received over 10,000 samples.

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 is attributed to Andy Caldwell unless otherwise noted, and reprinted by permission as part of his participation in the TEA program.

Related Web Pages

Ice Diary I: Shooting Stars on Ice
Ice Diary 2: Great Scott, A Ghost
Ice Diary 3: Cheer for Team Meteorite
Ice Diary 4: The Hunt Begins
Ice Diary 5: MacAlpine Hills or Bust
Ice Diary 6: Contacting The Mother Pod
Ice Diary 7: Summer Christmas
Ice Diary 8: Where No One Has Gone Before
Ice Diary 9: Climbing the Mountains of Mars
Ice Diary 10: Frostbitten
Ice Diary 11: Indiana Jones on Ice
Antarctic Search for Meteorites (ANSMET)
Planetary Materials Curation (NASA/JSC)
Mars Meteorite Compendium (NASA/JSC)
AMLAMP: Antarctic Meteorite Location and Mapping Program (database of where meteorites have been found)
National Science Foundation (NSF) Office of Polar Programs
McMurdo Long Term Ecological Research (LTER) project
Ice Cube of Exotic Microbes
Antarctic Microbes Colonize under Mars-like Conditions
Cryobot (JPL)
Meteorite Repository (JSC) Rock Descriptions
NIPR Meteorite Collection (Japan)