NSBF has launched a small balloon (called Pathfinder) to study the wind conditions at our flight altitude of about 125,000 feet (37 km). They get positions from the Pathfinder balloon every 20 to 90 minutes over the NOAA weather satellites orbiting the globe every 90 minutes. We will be able to use the same type of satellite link to get minimal communication with our payload once it is out of sight of Willy Field.
After dinner there was a science lecture on algae in the upper sea ice. The group's nick name is 'brine suckers' because they used to drill holes into the ice and collect the brine by sucking it out of the hole. When sea ice freezes, the salt is concentrated into small 'pockets'. In mid October the sea ice has a temperature of about -5 F (about -20 C) and the pockets are very small with a salinity that is 6 times higher than regular sea water. These pockets contain this highly salty water. When the air and ice temperatures increase, the pockets get larger and the salinity consequently decreases. The temperature of the ice goes up to about freezing and the salinity goes down to about sea water level in late December. This brine contains a lot of algae that are obviously able to live under highly variable temperatures and salinity levels. A nice feature of this brine is that with time the pockets get so large that they flow into the water below the ice. The brine can be much cooler than the sea water because of its high salinity. When the cold brine flows into the water, it freezes the sea water around it. A video was shown that showed the ice from below obtained by a diver. It showed stalactite-like features, that's where the brine flows into the water. It was interesting to learn that there is life within the sea ice at very low temperatures and very high salinities. These organisms seem to avoid freezing with organic sulfur compounds that are also released into the ice.
Here is some unrelated information of interest:
Scientists here get red parkas with a name tag. Support people get yellow parkas without name tags that do not look as nice as the red ones. It seems that being a scientist is a status symbol here. I slowly start to get some insight into the society here. Scientists seem to be considered to be at the top (probably the only place on earth). Non-scientists call them 'beakers' because of the many chemical and micro-biological experiments going on. I have some understanding for this. For example, the ASA people are normally not allowed to enter the Crary Lab. As scientists we got a special magnetic card that allows us to enter the building at any time and have access to many things such as free copy machines, powerful computers etc.
There are many recreational facilities here, such as a gym room to work out, a place to play volleyball and basketball, a climbing wall, a bowling room, several bars (non-smoking and smoking, no alcohol and alcoholic), a shop that sells the most needed items and a very limited number of souvenirs, and of course alcohol. The rations are large. Per week I could get 24 cans of beer, or two bottles of wine, or one bottle of liquor.
The roads here are dirt roads. It would be very hard to maintain roads with hard cover under these harsh conditions anyway. Now in summer, part of the ice and snow melts and the roads get rather muddy. McMurdo is therefore also called McMudhole. Actually it is not that bad. The soil here is mostly black, basaltic (volcanic) sand that does not stick too much to the shoes.
All vehicles including helicopters and aircraft are orange. I first thought that this is a good idea because orange is very easy to see on the white ice or snow. However, the real reason for this color is the fact that these are unarmed military vehicles, and international treaties require that they are kept in orange instead of the regular camouflage pattern or green color.
The runway on the ice close to McMurdo has been closed (because the sea ice is getting too thin) and the snow-field at Williams field has been opened. This means that only LC-130s with skis can land and take off. On the sea ice, the Kiwi C-130 (with more capacity than the LC-130) and the huge C-141 and C-5 were able to land. Therefore transportation is more restricted now. The ice on the sea is two years old. Last summer it did not get warm enough to melt. Therefore the ice is about 10-12 feet thick (3-3.5 m), while one-year ice would only be about 6 feet thick (2 m).
The carpenters worked (unexpectedly) on the door today. The door is made of canvas, but they obviously made it too short and the sides are not stiff enough. Therefore wind can blow inside the building and the door would probably not withstand a storm. One guy also sprayed a graffiti on the outside of the canvas door reading 'one big door for a pig barn'. It is the same guy who designed the door wrongly. He was fired the next day and was sent back on the next plane to New Zealand. If we push the folks here hard enough, we might perhaps move the gondola inside by tomorrow. We have been hoping to unpack the gondola on the next day for a week now, so nobody trusts any predictions anymore.
When I arrived at the wooden silo building, the gondola (a 6 by 6 by 14 feet metal frame (2 by 2 by 4 m)) was already inside the building. We discovered that quite some snow had gotten into the transport box (who knows how), but things looked quite ok. We then installed the main 80-cm mirror, which looked fine at that time. Russ then wanted to install the heat rejection mirror, which reflects most of the solar image back into space (otherwise our optics would be fried). While doing this he dropped this mirror onto the primary, which got damaged. We were very lucky because the damaged part will be covered by the heat rejection mirror and does not contribute to the light gathered by the telescope. We were very lucky and the incident tought us to be more careful. We went ahead and installed the graphite-epoxy tube surrounding the telescope, the liquid crystal modulators that allow us to measure magnetic fields, and the image motion compensation system, which stabilizes the solar light beam to better than 0.1 arcsec (an angle of 1 arcsec is 1/3600 of a degree). We also connected a lot of cables. We had dinner out at Willy Field in the Jamesway tent (asparagus, mushrooms, and a strawberry mouse) and worked until 9:15 pm, when we took the shuttle back to McMurdo.
We are now driving to Willy Field over the Ross Ice shelf, which is covered by a very thick layer of snow. This road tends to be very bumpy because there is no solid surface below the snow. A few vans or trucks with spinning wheels are enough to destroy the snow road. To keep the conditions at a reasonable level, heavy machines almost constantly try to flatten out the snow. There are several lanes that one has to drive in according to the vehicle type: tracks, 4-wheels, regular wheel, snowmobile, pedestrian, and cross-country skies. If there is any reason to wear seat belts here, it is not to bump with the head against the ceiling of the van. When a vehicle crosses from the Ross Island with its dirt road onto the snow of the Ross Ice shelf, the driver tries to remove as much of the soil on the bottom of the van as possible. This is not to avoid contamination, but the black soil of Ross Island on the snow absorbs more sunlight and therefore tends to make the snow very soft and actually 'burns' holes into the snow.
The weather here is partly cloudy, some snow is falling, and temperatures are around freezing.
I heard an interesting joke today about Antarctica. People going to Antarctica several times can be described as follows: The first time they go for the adventure, the second time they go for the money (salaries down here are good and expenses are very low), and the third time they go because they fit nowhere else on earth.
We were close to pointing the telescope to the sun when we went to see the launch of the next Patfinder balloon. The Pathfinder payload is very small and light and contains a satellite transmitter with a cellular phone type antenna. It also contains a GPS (Global Positioning System, a satellite system that allows pocket-calculator size instruments to determine the exact position on earth) receiver and 8 ballast cells that each weigh 1 pound (0.5 kg). The balloon was laid out on a piece of cloth, the estimated length of the balloon was about 20 m. The top was filled with Helium and then released. after 2pm. The first pathfinder launched about a week ago headed straight for the South Pole and rotated in the wrong direction around the pole. At present, the current balloon is going in the right direction. The large balloons (29 mio cubic feet) are launched in a similar fashion. The ascent is rather slow, but the Pathfinder reached 123,000 feet (37 km) in the late afternoon.
Around 4pm we reached track state 3 for the first time (i.e. the telescope found the sun on its own and kept the solar image in the TST for about an hour), about 2 hours after rolling out the gondola on the A frame. The main problems we had were gain settings for the tracking controllers (which were set for the long balloon cables and the solar panels on, right know we hang on short chains on an A-frame and the solar panels are not yet mounted) and a bug in Phil's code. We tested the emergency procedure (stowing the telescope into a secure position) if the balloon should fall below 90,000 feet. The test went well. The TST beam looks good and also the main telescope beam looks encouraging. After dinner in the Jamesway tent (spaghetti, salad, garlic bread, strawberries in chocolate cover), we used the gondola inside the Silo with the heliostate (two mirrors that deliver a solar beam inside the building) to illuminate the TST. I adjusted some more lenses. Kim and Graham worked on a radio communication problem.