Today was the yearly art exhibition at McMurdo: There were pictures, drawings, sweaters (knitted), fridge magnets, woodwork etc. produced by people down here over the course of the last few months. Some of them were for sale.
The science talk focused on glaciology and climate. Before the talk, the NSF Rep (representative) told us that the Russian Vostok station on the Antarctic plateau (about 10,000 feet (3000 m) altitude) has to shut down because they run out of supplies. The Russians tried to move supplies from an other base of theirs at at the coast but the convoy broke down half way with no spare parts left. The US is helping with LC-130 flights and brings the Russians to McMurdo. They also support the ice drilling project at Vostok that delivers ice that is up to 200,000 years old. The science talk was about using ice for climatology on Taylor dome, a hill of ice about 100 miles from McMurdo. They have one drilling hole that is 550 m deep, 3 at 100 m, and several at 10 m. The ice contains records of past temperatures at the surface. For example, the ice temperature in Greenland at a depth of about 1 km is still cool from the last ice age. People make use Taylor dome because the ice can only flow away from there, which prevents a mixing of temporal and spatial patterns. They measure temperatures in the bore holes to see how the temperature changes in the ice. They also determine ice drifts by optical means and with GPS (Project S-171). At Taylor Dome they can go back about 120,000 years. An interesting period is around 1965 when most atmospheric nuclear tests were performed and the ice shows a marked increase in radioactivity. The ice is drilled with an organic fluid to keep the hole open (the ice around the hole is under large pressure and would close the hole in a short time unless it is filled with a fluid that has about the specific weight of ice) and ease drilling. This fluid is recycled. Scientists have also started to use Automatic Weather Stations to understand snow accumulation and temperatures in the air, wind directions etc. to understand the formation of ice on Taylor dome.
The weather was mostly cloudy, a little windy, and got more sunny in the evening. Kim, Harry, Russ, Graham worked at Willy Field.
Before noon we were hit by condition 2. The wind reached probably about 50 miles/hour (80 km/h), it was snowing, and the visibility was restricted. Nevertheless, we got our wind-breaker pants, bunny boots, balaclavas (face masks) and parkas with thick mittens and marched to the Jamesway for lunch. Around 3pm the NSBF guys and Phil and Russ left for McMurdo. The NSBF guys made it about 100 m from the silver barn when they got stuck in a snow accumulation and had to use a Spryte (track vehicle) to free their van. They barely made it to McMurdo and arrived there with the transmission broken (worn down). Phil and Russ were a little more successful on the regular shuttle. Shortly afterwards condition 1 was declared for Willy and the road to McMurdo. We were stuck at Willy and had leftovers from lunch (re-heated) for dinner. After 9pm we were able to drive a van back to McMurdo once condition 1 was lifted. The strong wind and snow fall produced large snow accumulations in short time, some of them reaching 1 meter in height.
JACEE was prepared for launch around 2pm. We had to redo our laser-setup because the JACEE solar panels had to be moved out of the silver barn through the wooden silo building we were using. The weather got very nice and after dinner in the Jamesway I watched the preparations of the launch, which took place at 8:30pm with a 29 mio cubic feet balloon. It was very impressive. The balloon is only partially filled with helium since it will expand to its full size only in the stratosphere. There the balloon will have a diameter of about 100 m and is about 200 m tall. It can be easily seen from the ground even at that altitude. It takes about 5 hours to get to 37 km. We headed back to McMurdo afterwards. I shot about two rolls of film since the weather might be worse when we launch and I might be busy during other things then. The temperature was well below freezing but the strong sunlight didn't make me feel the cool temperature.
It was the second day with clear skies and we therefore moved the telescope out. I aligned the main telescope and the small TST (Target Selection Telescope), and aligned the beam of the main telescope to the CCD camera. Everything seems to work quite nicely, but the image quality after the Barlow lens is very limited at the moment, but at least all lenses and mirrors are hit in their centers. The TST beam is still not optimal. We tried to test and lock the IMC described above, but the seeing (atmospheric turbulence) was way too bad to do that. We did some tests of automatically pointing the telescope to the sun, which worked quite well outside of the silo, but dumping momentum gives us pointing problems because of the short cables to the A frame. On the balloon, the gondola will hang on long cables, which will avoid this problem.
Later in the afternoon, I accidentally broke a bow of my prescription sunglasses. I got back to town around 8:45 pm and just heard the last part of a science talk on the use of GPS in Antarctica.
Later that night I heard that we were close to a disaster again. Kim tried to fill the pressure vessels that contain all our electronics and computers with pressurized air. After pressurizing the first vessel, he noticed that the compressor is used to drive tools, and therefore adds oil to the air to lubricate the tools. Fortunately, when Kim filled the first vessel, the pump that drives the oil did not come on, so that there should not be much oil in the first vessel. Nevertheless it has to be tested again. Afterwards the oil pump came on and produced a real mess outside the pressure vessel. We now use dry nitrogen to fill the vessels.
I built up the spectrograph with Steve, but we had quite some problems to align the whole thing while the main telescope is fed by a small heliostate (two flat mirrors that send the sunlight into the wooden silo). We managed to put all filters on band at a single temperature by tilting them. We then mounted the Fabry-Perot (a very narrow-band filter that can be tuned by applying a high voltage) and checked it at H-alpha. Things seem to work ok. In the late afternoon clouds came up and we couldn't finish testing. The NSBF guys started to set up their computers for our flight and the solar panels. Our panels have been pout together yesterday (and deliver about 1 kW).
The weather was quite nice all day long and very warm, certainly above freezing. It is interesting how a little dirt makes the snow melt locally and very mashy. Clean white snow is still hard.
We went back after 4pm to go to the Christmas dinner. I had a shower (I must admit for more than 2 minutes) and dressed up in the best clothes I had with me. Dinner was served in 3 shifts starting at 3pm and changing on the full hour. We had (free) tickets for the 6pm shift. Since this was the last one, we were able to sit at the tables for much longer than an hour. Dave had brought along champagne and wine. Dinner consisted of turkey, Antarctic cod (fish), and Australian lobster as the main course, and lots of different sweets for dessert. There was a small Christmas trees with some electrical light and an ad-hoc brass band trying (hard) to play some Christmas songs.
I went for brunch at 10am after a good night's sleep. At 10:50 am I went to Willy Field with the NSBF guys because I couldn't find anybody else of our crew and called Willy Field, where they were already working. The NSBF guys didn't get off a day over Christmas because JACEE is in the air. I spent most of the time working on the main telescope. It was sunny and we were able to keep the telescope pointing to the sun during most of the time. When I arrived, Dave and Kim had already installed a video camera at the place where Kim's silicon retina (an artificial eye that can detect the motion of patterns and steer a mirror such that the pattern will be stable) will be located. After adjusting the focus of this camera, we were able to see solar granulation (a convective pattern that covers the entire sun) through the main 80-cm telescope. This confirmed that the main telescope is not completely misaligned. Next, we tried to get images with the large Kodak CCD camera (1000 by 1500 pixels) through the main telescope. Unfortunately this was a real disaster. After some investigations I realized that probably a lens has not the focal length it was supposed to have. Indeed, Dave had changed the focal length of one lens and the optical design did not get adjusted to that change. We also had a leaky pressure vessel today. No time and effort was invested to keep the surfaces free from scratches while the vessels were open. When one of the vessels was leaking today, Phil found and removed scratches on matching surfaces through which air was leaking. We use pressure vessels around the electronics so that we can use standard, cheap components that would not operate at the low pressure of the stratosphere. Late in the afternoon clouds came up and we headed back around 6pm. Dave drove the van about 10 m when he got stuck in soft ice to the axes. It required a Spryte (track vehicle) to get it out. Dave was not too pleased with everybody taking pictures of the van in this uncomfortable position.