"SPIREX Ascends and the 100,000 Year Snow Storm"

Jim Sweitzer - January 10, 1995

    Today was an important day for the SPIREX team. SPIREX stands for South Pole Infrared Explorer. It is a telescope designed to observe the sky at near infrared wavelengths. Last year it achieved fame by making unique observations of the comet collision with Jupiter. But it was only on a temporary pier back then.

Right after lunch, riggers, and heavy equipment operators arrived at our observatory building. The temperature was high, only -10 F, and very, very light snow flakes were falling. You almost had to look for them they were so few and far between. Next to the building is a 36 foot tower that was specially designed to keep the SPIREX telescope high above the snow pack. Next to the building and tower, SPIREX seemed very small. SPIREX isn't a particularly large telescope -- the mirror is 24" in diameter, but it is very specialized and massive. It weighs about 8,000 pounds. So, it had to be lifted by a bulldozer with forks just to bring it next to the crane that would take it for its last ride. Slowly and gingerly they proceeded with the telescope held out in front of the tractor. Down here in Antarctica the construction vehicles look pretty much the same as back in the "real" world. That's because the snow here isn't much different in consistency than the dirt you'd find at a construction site.

After about ten minutes of crawling, the telescope is eventually in reach of the crane. Riggers and SPIREX scientists then connect a triangular frame to the crane and hoist it above the telescope. Next chains are attached to the telescope mount and to the frame. Everything is checked and double checked before this unique telescope is lifted high into the air. There is some concern, because the crane that must make the lift has been driven up onto a snow berm about 10 feet high. The worry is that the extra weight of the telescope on the long crane resting on relatively soft snow might make the crane tip. We are instructed to stand clear of the direction in which the crane and telescope would fall.

But it never does. The telescope is quickly lifted and the 50 foot crane boom never sways. SPIREX scientists, engineers and students now ring the place on the tower where the telescope will rest. Carefully they crouch down and guide it to its three mounting bolts. As it slips down over the bolts it is a perfect fit. Everyone stands up and breaths a sigh of relief. Then they all dash for their cameras and hand them to me. For ten minutes I take group shots so that the event is recorded on everyone's film.

After the crane lift I had a discussion with Fred Mrozek, the engineer who designed the SPIREX telescope. But we weren't talking about the telescope. Rather, we were remarking on how slowly the snow was falling. This rate was typical, since the Polar Plateau only receives a few inches of snow per year. A quick calculation made us realize that the 2 miles of ice we were standing on top of was the result of a 100,000 year snow storm still in progress. It actually has been going on longer, but this is about the time it takes the ice to slide off the continent. It is only able to accumulate for that long.

Fred and I both remarked how rare such opportunities to perceive deep time are. We also both simultaneously remark that this Antarctic time scale is the same as the time it take for light to cross our galaxy.

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