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NOTE: most of the images in this document can be viewed at the maximum resolution of your monitor by clicking on them (you can then right-click on this image, save it to disk, and re-open it to see the full-resolution of 2048x1536 pixels).
Six years after my first South Pole diary, and three years after my last antarctic adventure, I am returning "to the ice".
Four of my colleagues, Paolo Calisse, Jon Everett, Andre Phillips, and John Storey, have already headed south this season. Two of them, Paolo and Andre, are currently in Antarctica. One of them, Paolo, has just completed a two-month highly successful stint at Dome C, a remote French-Italian base high on the antarctic plateau. The plan is for me to meet up with Paolo and Andre in McMurdo, the US station at latitude -78, and then to take the next available flight to the Amundsen-Scott South Pole Station.
The last few months have seen an extraordinary amount of activity in the antarctic lab of the School of Physics, University New South Wales, culminating in the completion of two new instruments: SUMMIT, designed to measure the sub-millimetre emission from the atmosphere, and ICECAM, an instrument designed to measure the amount of cloud cover during the long, dark, antarctic night. Both instruments are crucial to our goal of establishing an astronomical observatory in Antarctica.
This work is in collaboration with the US Center for Astrophysical Research in Antarctica (CARA), which is a consortium of US universities.
Today is a hot, oppressively humid, summer day in Sydney. Jon Everett and I worked till late in the previous evening to ensure that the 25 kg of scientific equipment that I am taking to the Pole was fully-operational and well-packed. It is a relief now to settle back on the aircraft for the short hop to Christchurch in New Zealand, which is the gateway for the US flights to Antarctica.
Christchurch is a very pleasant city, which today was experiencing a cold southerly wind which saw the temperature plummeting to 20C despite the cloudless summer sky. After checking into my hotel at 3 PM, I took a bus into the city and headed for the Christchurch Botanical Gardens, which are spectacular during the summer. I used the opportunity to practice with my new Sony digital still camera, taking numerous close-up photographs of roses, two of which are displayed here for your viewing pleasure.
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Walking past the Dux de Lux restaurant, a popular haunt for antarctic adventurers in Christchurch, I happened across an international busking festival where a dozen or so buskers were trying their luck in front of an appreciative audience of about 1000. The restaurant was booked solid, so off I went across the road to the Le Bon Bolli for dinner. Le Bon Bolli is a French restaurant, where the waiters all speak with outrageous French accents, although my waiter, after greeting me with "bon jour", later confided that he was in fact Ukrainian. The decor of the restaurant also strays from pure French, with Germanic influences and a particularly impressive Italian ceiling. The photo shows the view directly up from my table.
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In the morning it was off to the CDC, the Clothing Distribution Centre, for fitting out with my ECW, extreme cold weather, clothing. The CDC is incredibly well organised, and in just 30 minutes they fit you out with a complete set of clothing that allows you to withstand the severe conditions in Antarctica. You get a pair of air-insulated rubber "bunny boots", six different pairs of gloves, six pairs of thick socks, two pairs of expedition underwear, various layers of thermal suits, a polar-fleece jacket, a balaclava, a neck tube, and culminating in a thick parka that is two or three times the weight of the heaviest you would find at any ski resort.
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About fifteen other people were being fitted out at the same time as me, and there was the usual mixture of OAEs (Old Antarctic Explorers, i.e., people who have spent a significant amount of time on the ice), pseudo-OAEs (those that have yet to clock up enough ice-time) and first timers, who can be easily recognised by their faint look of unease during the safety briefing. Detecting the pseudo-OAEs is more difficult. When we were told that "this year you will be relieved to know that we have secured lightweight Thermax underwear, which you can request to replace your expedition underwear" the pseudo-OAEs gave themselves away with their "gee, what a relief" and "about time" and "I wish I had had those when I fell down the crevasse" comments. I smiled inwardly, and tried to emulate the somewhat bemused indifference of the true OAE.
After clothing issue, I worked on some software to decode the Argos satellite transmissions from our ICECAM experiment. Paolo turned ICECAM on yesterday at Dome C, and every two hours it broadcasts 32 bytes messages to the Argos satellite network. The first batch of messages just came through via-email from the Argos ground-station, and the instrument looks healthy.
Back at the hotel I learnt that I am scheduled to report to the airport at 0615 for the 7-hour flight to McMurdo, this will be on a Kiwi C-130 Hercules aircraft. My first time with the Kiwis.
In the evening I downloaded photos from the Sony camera, and started dictating these diaries (I'm using some voice recognition software which works very well).
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Up at 5:00am in order to make it to the Antarctic Centre for the 6:15am check-in. About 40 PAX (passengers) are on this morning's flight. We all get dressed in our ECW gear, check in our baggage and then have 30 minutes to grab some breakfast at the Antarctic Cafe.
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Then its back to the Antarctic Passenger Terminal for our safety briefing, prior to being bussed to the waiting C-130 Hercules.
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The C-130s do not have skis, which means that the trip is 7 hours rather than 8 (since the drag is less), but the disadvantage is that they can only land on the Pegasus Blue Ice Runway, which makes it more likely for them to "boomerang" in the event of poor weather.
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The C-130 is completely packed. 40 PAX and 3 huge pallets of stuff. Twenty minutes after take off the pilot said "OK, you can undo your seat belts and move around the aircraft and find a comfortable place for the trip". I immediately scampered up on top of the closed cargo pallet and staked out a location where I could lie down. There was less than 0.5m of space between the top of the palette and the ceiling of the aircraft (which is full of pipes, wires, control-lines, etc). Worse still, the pilots always turn up the heat after take-off. It was 30C where most of the passengers were, and 35C where I was. Given that we were all wearing Extreme Cold Weather clothing, this makes it very uncomfortable. But this is just the way it is always done on flights to/from Antarctica. The aircrew wear light-weight clothing and have stretchers at the back of the aircraft where it is 10 to 15 degrees cooler.
The photo shows the view from the top of my palette. You can see how closely the passengers are packed; and this is with about half the passengers scattered around the rest of the aircraft.
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The next photo shows a bunch of people on the palette behind mine.
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And here is an exciting view of the urinal at the back of the aircraft. Fun, fun, fun.
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Five and a half hours into the flight we catch our first glimpses of Antarctica through the tiny portholes in the side of the Hercules. It is a truly awesome sight. The chances are that no human has ever been in the area we are flying over.
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After 7 hours we make a beautifully smooth landing at Pegasus, and disembark into the bright blue -6C weather near McMurdo.
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Within minutes we clamber aboard Ivan the Tera Bus for the hour-long, agonisingly slow, drive to McMurdo itself.
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On the trip we catch some superb views of Mt Erebus, an active, ice-covered volcano.
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Upon arrival at McMurdo, we drop into the Chalet, which is the administrative centre of the town. Just as Brian Stone, the NSF Science Representative started briefing us, I felt a tap on my shoulder; it was Paolo, he had flown in from Terra Nova Bay in a Twin Otter aircraft just ten minutes before our flight landed.
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John Storey later commented that some time during the day Andre, Paolo, and myself were all airborne over Antarctica (Andre was flying from McMurdo to the South Pole).
We collect our room assignments, and off we go for dinner.
Dinner is served in the McMurdo Galley. The Galley is a vast improvement over the situation I encountered on my earlier two trips to Antarctica. Then, it was divided into two window-less, low-ceilinged, sections: the O-side for Officers and the E-side for Enlisted men, this being a remnant of the military history of the town. And the food was indescribably bad. In the last year the Galley has been completely remodeled with large windows overlooking the spectacular antarctic scenery, and high ceilings to give the impression of space. And the food is delicious.
After dinner Paolo and I retired to the Crary Lab for a long discussion about his last two months at Dome C. We also phoned our wives (yes ladies, we are already spoken for) using some PC-to-phone software, which works excellently.
The Crary Lab has a very pleasant library and computer area with vast windows giving a 180 degree view in the direction away from McMurdo across the Ross Sea. There is a small telescope set up so that you can spot seals and penguins. There are lots of seals around today but no penguins in view. The Ross Sea itself is completely frozen, apart from a channel that has been forged by an icebreaker. Normally by this time of year there is open water within sight of McMurdo, which greatly simplifies unloading the various cargo ships that come towards the end of the summer season. A Russian ice-breaker tourist ship (visible in the next image) is visiting at the moment.
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We finish our conversation at 1 AM, and I have to get up at 5:30 AM for the flight to the South Pole. Paolo won't be coming with me because there is an over-population at the Pole and there isn't even one spare bed.
At 8 AM, six other passengers and I are delivered to Willy Field, and we take off on a ski-equipped LC-130 for the final three-hour leg of our journey.
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Due to cloud there isn't much of interest to see through the portholes of the aircraft, so most of us try to catch some sleep. After 2 1/2 hours the pilot instructs us to prepare for landing, and shortly thereafter we make a perfect touchdown and we hear the sound of the skis sliding along the runaway (I later learnt from a pilot that the friction of the skis on the ice is sufficient to heat them up so much that when the plane finally stops, up to a metre of snow can be melted and stuck to the bottom of the skis; this can make dislodging the aircraft impossible even with full thrust, requiring the air crew to use shovels to dig under the skis).
Just before the Hercules slid to a halt, the Loadmaster (the member of the air crew in charge of operations rearward of the cockpit) opens the rear cargo doors and we are engulfed in the rigid polar air. The ambient temperature is -26C, which is actually warm for this time of year.
Here is a 0.8MB movie of disembarking at the South Pole.
And here is a 5.4MB higher quality version of the same movie.
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We rapidly disembark and are herded towards a waiting vehicle for the short drive to the centre of the US Amundsen-Scott South Pole Station: the Dome. Apart from the temperature, the other thing that immediately strikes you about the South Pole is the lack of oxygen due to the relatively high altitude.
The air pressure today is the equivalent of an 11,000 foot mountain, which means that the oxygen level is about 67 percent of that at sea level. If you make a rapid transition from sea level to 11,000 feet, as we had just done, it comes as quite a shock to the body and it can lead to various degrees of altitude sickness, ranging from slight headaches, nausea and sleeplessness to cerebral embolisms and death. The other noticeable effect is shortness of breath when trying to climb stairs. The best cure for altitude sickness is to rapidly descend to a lower altitude, but this is impossible at the South Pole since the altitude is the same for hundreds of kilometres in every direction. So here the remedy is to put you in a pressurised bag and pump you up to the equivalent of sea level.
After a bite to eat the new arrivals at the Pole go to the upstairs Galley area for a briefing by Katy Jensen and Alexandra Brown, the Area Manager and Assistant Area Manager respectively. We are told the rules of the station, and the list of ten transgressions that will get you immediately sent back to McMurdo; an example is attempting to visit the Old Pole Station, which is now buried under the ice about 1/2 km from the Dome. We are also given our bed assignments: I am in Fred 7, a hypertat in the "Bedrock" complex consisting of hypertats Fred, Barney, Wilma, and Betty.
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Most of the people on the station are accommodated in the village of Jamesways in a section of Summer Camp built on a plateau of snow. Jamesways are similar to the hypertats, except that their outer skin is canvas rather than metal. Each Jamesway/hypertat sleeps about 8 people in individual bedrooms on either side of a central corridor. The Jamesway design was developed during the Korean War, and works surprisingly well in Antarctica. Each Jamesway is heated by a noisy burner using JP-8 fuel. When you consider the noise from the burners, the ever-present bulldozers, and up to seven LC-130 flights per day, the South Pole suffers from considerable noise pollution.
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In the evening I come down with a mild case of nausea due to altitude sickness, but this goes away after a few hours.
When I awake in the morning I discover Paolo in the Galley - he had arrived an hour earlier from McMurdo. We both visit the AASTO (the Automated Astrophysical Site-Testing Observatory, where most of our experiments are located) and are taken aback by an ominous smell of gas. I arrange to borrow a leak detector from the station's Environment Health and Safety Officer, and discover that several joints in the butane thermosyphon are leaking. Fixing these will be quite difficult since the joints are almost inaccessible; this will have to wait till Bob Pernic arrives on Thursday. Bob knows how to solve all mechanical problems.
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An unusual sight greets us on the runway this morning: a Hercules sitting with its engines off. Normally the pilots leave the engines running while at the Pole, since they can be very difficult to restart once they become cold (this is particularly true later in the season where temperatures can reach -50, at which point the JP-8 fuel becomes quite viscous).
Later at dinner I sit down next one of the pilots and ask him what is going on. He explains that just as they were landing, the tailpipe of the left-hand outboard engine dropped off, presumably due to metal fatigue. This is actually a moderately serious occurrence, since the tailpipe feeds the turbofan, and if it drops off the engine power is dramatically reduced. The pilots are now stranded at Pole until a replacement back-end for the engine can be flown from McMurdo. The air crew will be sleeping in the biomedical building, since the doctor is worried that they may get altitude sickness overnight.
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Chatting with the pilot was most interesting, I learned all sorts of new things about Hercules aircraft, most of which I would have been better off not to know.
For example, no Hercules had ever been able to make an emergency water landing without fatalities. What tends to happen is that the nose of the aircraft breaks off and the pilots don't survive. If a Hercules had to ditch in the Southern Ocean between New Zealand and Antarctica, the chances of survival would be very slim. While each aircraft carries rafts and dry suits, there would not be time for everyone (or indeed anyone) to suit-up before the aircraft sank.
Another interesting bit of information was that the friction on the skis makes it very difficult for the aircraft to reach takeoff speed; once, on the antarctic plateau, they had to travel fifteen miles at full thrust along the ice before they managed to lift off, and this was only due to a bump in the ice that was sufficient to get them airborne. Once in the air a ski-equipped Hercules is traveling only marginally above its stall speed and doesn't have directional control. If an engine fails at this point, the only alternative is to shut down the corresponding engine on the other side, and land in a straight line. So you have to make sure that there is a suitable landing area immediately ahead of the runway.
Andre, a pilot himself, got on like a house on fire with the Herc pilot. They discovered that they both had float-plane licences. "Yeah, once I was taking a J17, you know, the one with the pre-stressed horizontally-opposed gyro-flaps, lake-hopping in upstate New York when the stabiliser broke loose. The transverse control strut was vibrating like crazy, it was all I could do to keep her steady. Jeez I was relieved to land on that lake!" "Yeah, I always preferred the J18 myself. More forgiving in emergencies." etc, etc.
Today all three of us got stuck into unloading our cargo and organising the AASTO. The AASTO is quite a small box, designed to fit neatly into the cargo area of an LC-130, and conditions were rather cramped with three of us trying to work.
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We discovered that the ignition system for our thermoelectric generator has a problem which results in the igniters being triggered about once a second. This generates a lot of electromagnetic interference, so it is something that we need to fix.
Back at the Dome, I passed by the laundry and discovered how they the wash socks of the 200 or so people on station (and remember that we are allowed only two 2-minute showers per week, to conserve water). They put all the socks into a big vat filled with lukewarm water and then pummel them up and down, by hand, with wooden boards attached to sticks. After a couple of hours, this produces a thick dark brown liquid, which they pour off into trays and slowly dry under banks of infrared lamps. The resultant brown powder is scraped off, put into jars labeled "Folgers Coffee", and served in the Galley.
Paolo, Andre, and I have decided to work slightly different shifts so that we can make productive use of the small amount of space in the AASTO. Paolo is on a 7-21 shift, I'm on the 14-4 shift, and Andre takes 18-8.
By the time I get out to the AASTO, Paolo has single-handedly placed the SUMMIT experiment on the roof, and has the instrument working. There is much rejoicing that it survived the trip from Dome C, where it has been collecting the first-ever measurements of the sub-millimetre emission from the sky there.
There is one problem with SUMMIT: its Dallas temperature sensors are not being reliably read by its computer. We will need to work on this.
I re-installed the SODAR laptop, with upgraded software, and the SODAR (sonic radar) is now making its characteristic chirps across the antarctic landscape. A half-dozen people asked what the noise was. The SODAR is able to measure the wind speed/direction and atmospheric density in 30-m increments from ice-level to an altitude of 1km.
Incidentally, for more information on all our experiments, visit the AASTO homepage.
Today, Paolo took the NISM experiment apart, to fix a problem we had last year with a slipping gear. Memo to instrument designers: never, ever, use grubb screws.
I started work replacing some corroded spade-connectors on the TEG ignition system. The corrosion is due to a previous episode of loss of freon coolant, which resulted in the entire AASTO being exposed to a mixture of hydrofluoric and sulphuric acid vapours for 6 months.
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Andre shoveled snow. His many years of experience in the antarctic tells him that if we don't clear the front of the AASTO soon, it will be buried within a matter of months. The surrounding snow level is 1.5 to 2m above where it was when the AASTO was installed in 1997. The precipitation is only 0.2m per year, but any sort of structure tends to attract snow, since it creates turbulence which causes suspended snow particles to drop out of the air.
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In the late evening we were treated to a spectacular example of sun-dogs and arcs, including the rare secondary arcs and upturned parabola. These are caused by sunlight bouncing off "diamond-dust" (sub-millimeter sized cylinders of ice).
The images do not do the display justice, since my wide-angle lens is insufficient to capture the full display. In the magnified views you can see bright specs: these are individual diamond-dust particles.
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Today we are very concerned about our experiment called ICECAM. ICECAM is designed to take images of the sky every two hours throughout the year and store them for later inspection. Paolo installed ICECAM at Dome C, some 1500 kilometres from here, about a week ago. It is in a "crypt", about seven metres below ground level - the reason for this is that during winter time it is warmer below the ice than on the surface. ICECAM is connected to an Argos transmitter - every two hours it sends a summary of the data to a low earth orbit satellite.
The problem is that we haven't had any communication from ICECAM in two days. The Dome C station will be closing in four days time, so there is very little opportunity to fix problems. We decide to make a high-frequency radio call to Dome C, and Paolo goes to the communication room and fires up the radio transmitter. He is soon having an animated conversation, in Italian of course, with the radio operator at Dome C. Everyone at Dome C knows Paolo, and there is much joke swapping and general hilarity. He is nicknamed (translating from the Italian) "Roman of shit" which apparently is a term of endearment.
Paolo arranges to have an electronics engineer inspect the Argos transmitter. An hour later we have the news that the DB-25 connector that joins the ICECAM computer and the Argos transmitter had fallen out, probably due to the cold. The engineer reinserted it and secured it with screws. We are hopeful that this will fix the problem but we have to wait for between 7 and 24 hours to find out, this being the delay between the Argos satellite receiving the transmission and an acknowledgment e-mail being sent to us.
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The food at the South Pole is almost always excellent, which is a remarkable achievement when you consider how isolated we are. We even have fresh lettuces from the "Freshies shack", which is heated to avoid freezing (rumour has it that there is good coffee stored there under lock and key). We take our meals in the Galley under the Dome. The Galley has two disadvantages: it is too small for the 200 people at the station, and it has no view to the outside, so you may as well be in a submarine.
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The Galley in the new South Pole station, currently under construction, promises to be a vast improvement. It will have magnificent sweeping views across the plateau. The "tin can" (or "beer can" as it is sometimes called) at the left of the photo encloses a staircase that allows access from the machinery arches and Dome. About one-third of its length is under the snow.
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Today's main task is a difficult one: we are going to install a 50-m fiber-optic cable from the AASTO to the AFOS telescope on top of the GTOWER. The cable has to be pulled through a conduit, and attached to the telescope via an injection module. The purpose of the fibre is to carry star-light from the telescope to a spectrometer in the AASTO.
Incidentally, you will note that there is no cover (or "dome") for our telescopes. There is no need for a cover since the only form of precipitation at the Pole is wind-blown ice-crystals, and these disappear with the next gust of wind.
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Fortunately the wind is very low today, which makes working on the tower much easier, despite the temperature of -38C. Last year Paolo did this job at -47C with a stiff breeze, and acquired some nasty frostbite on his hands. Note that the wind never gets strong at the Pole: the howling gales that are often associated with Antarctica occur only on the edges of the continent, over 1000km from where we are now.
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Andre and I spent a total of about six hours outside performing the fibre installation, 1.5 hours of which were required to affix two small bolts on an almost inaccessible clamp on the GMOUNT. This required us to take our gloves off, and pass our hands between two metal plates. Touching either plate with bare skin gives an instantaneous burning sensation. At most, 30 seconds is available for each attempt to install the bolts. Memo to the clamp designers: you can run, but you can't hide.
The fibre installation is finally successful, due in no small measure to the superb design of the cable and terminators by Ceramoptic and Jon Everett, our colleague back in Sydney.
Paolo spent most of the day in the machine shop working on modifications to the NISM instrument to improve the reliability of its moving parts.
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We have diagnosed the problem with SUMMIT's Dallas sensors, and suspect a static-damaged DS1481 IC (static electricity is a major problem at the Pole due to the exceedingly low levels of humidity). Unfortunately, this is one component for which we do not have a spare, so we send an urgent e-mail to UNSW seeking a replacement. Jon Everett rushes into work and makes up a package for FedExing first thing Monday.
Earlier in the day I played "dozer-tag", this is where you spot a Caterpillar tractor going about its business, and contrive to walk 50-m in front of it. When wearing all of your ECW gear it is difficult to keep track of what is behind and to the side of you, so it is not unusual for Caterpillar drivers to be faced with wayward "beakers" - the Antarctic word for "scientists". You turn around, pretend to be shocked that the tractor is heading straight for you, and then make some futile attempts running back and forth to get out of the way. The driver normally plays along and pretends to go after you. Hopefully, it all ends with smiles all round.
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In the morning Paolo put NISM back on the AASTO roof, and in the afternoon we were able to test its various subsystems. After fixing some minor electrical problems, everything worked perfectly. The only problem was that the optics box was 180 degrees out of phase with respect to the detector box. Unfortunately, this means that we have to take NISM off the roof and back to the workshop. If we don't, NISM will spend a year looking down at the ice rather than up at the sky.
Bob Pernic came over, and with Charlie Kaminski's help we cooled the AASTO to ambient (to reduce the pressure in the butane thermosyphon system), and then tightened some of the joints and used an acetylene torch to fix some leaks in the outside condenser.
Unfortunately, after refilling the system and restarting the TEG, all but one of the leaks was still there, albeit reduced. The plan is to replace the big, ugly, thermostatic valve with a spare we have, and redo the outside connections tomorrow.
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Paolo has discovered that a bicycle makes a rapid form of transport in the icy conditions. You have to be very fit to ride a bike here since it is easy to over exert yourself and run out of oxygen. In the thin atmosphere it takes some time to get one's breath back. Paolo is in good shape since he has just spent two months at Dome C, at an even higher altitude.
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By now we should have received some Argos messages from ICECAM. The fact that we haven't is worrying us greatly. Dome C station will be closing in two days from now and many key people, including the helpful engineer we contacted earlier, have already left. The remaining people are very busy closing the station. We decide to try making radio contact again. Paolo spent most of the afternoon on the radio; it appears that ICECAM itself is working, although there could be an intermittent fault in the DB-25 connector. Paolo gives detailed instructions to a technician to clean the connector and spread the contacts slightly to try to achieve better electrical connection.
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By the time we receive confirmation via e-mail that the Argos transmissions are getting through (or not, as the case may be), Dome C will be closed. So we have done all we can.
With NISM back in the workshop, Paolo corrects the 180 degrees phase error, and use the opportunity to improve the limit switch brackets. This takes most of the day, and results in a huge pile of aluminium shavings and two tiny brackets.
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Bob Pernic and Charlie Kaminski make a second attempt at fixing the butane thermosyphon leaks. It is very difficult to work outside today since the wind is exceeding 14 knots, giving a wind-chill temperature of -59C. This time they are successful, and the system passes a leak test.
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In the afternoon we obtain a spectrum of the sky through the AFOS spectrometer, thereby verifying that yesterday's fibre installation was successful.
We take a publicity shot of the Andor CCD camera that is used in the AFOS spectrometer. Andor is a high-tech company based in Ireland, and has been particularly helpful in supporting our Antarctic program.
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While we are in the photo-taking mood, we take some additional shots at the Ceremonial Pole, a shiny metal sphere on a barber's pole surrounded by the flags of the Antarctic Treaty nations, and the Geographic South Pole, just a few tens of metres away.
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Watec is another company that has been very helpful to us, and I am holding one of their tiny CCD cameras in my gloved hands in the photo. We have verified that the Watec CCD cameras can operate down to -80C (way colder than its specifications) in our test chamber at UNSW. The ICECAM experiment uses one of these cameras.
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And here is close-up photo of a Watec CCD camera on top of the South Pole marker. This marker is within a metre of the actual point about which the earth's rotational axis intersects the earth's surface. Another way of thinking about it is that it is the point at which all the lines of longitude come together. If you walk around this marker you will pass through all 360 degrees of longitude.
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Andre's GPS receiver reads a latitude between -89:59:59 and -90:00:00 when placed on the marker. And here is a photo to prove it.
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The evening's e-mail brings no news of Argos transmissions from ICECAM, so we will just have to hope that the instrument is working and that when we return to its crypt 7m below ice level at Dome C we will have a year's worth of data. It is a great disappointment that we won't have real-time feedback during the year, but hey, its a harsh continent (as the saying goes).
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Andre has been concerned about the ice buildup around the AASTO, and today he organised a Caterpillar tractor to bulldoze to a depth of between 0.5 and 1m. You can't see it in the photo, but the AASTO is sitting in a depression about 1.5m below the surrounding ground level. There was no depression when we installed it 4 years ago.
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Meanwhile, I continued to work on some of the electronics problems that we had last year. For example, the act of switching on a quartz-iodine calibration lamp reboots the AFOS computer. This turned out to be due to a 470uF capacitor that was pulling down the main supply rail for a millisecond when the lamp was first turned on. I also tuned-up the NISM chopper motor driver, and installed a software-controlled servo-loop that stabilises the chopper frequency as the ambient temperature changes.
In the evening we aligned the AFOS spectrometer, a tedious
task that took several hours. The result was very satisfactory.
You can see the spectra from the six individual fibres in
the image. Three of the fibres cover the red end of the spectrum (at the
left of the image), and three cover the blue end. The structure you seen
in the spectra is due to a combination of atmospheric absorption and
absorption in the fibres themselves.
I added the colours to the above image; they are approximately correct.
Today the NISM experiment was finally installed on the AASTO roof. After some problems with limit switches, and a calcium hydride canister that was too large to fit the NISM housing, all of the functions checked out perfectly. NISM is designed to measure the sky emission at 2.35 microns, a wavelength in the infrared where the South Pole sky is 100 times darker than that at typical temperate-latitude observatories. This is one of the reasons we want to build a telescope in Antarctica (the other reasons are: Antarctica is the driest continent, so there is less water-vapour in the air to absorb radiation from the universe; the antarctic plateau is quite high, so there is less air to look through; and the lack of a daily heating cycle makes the air above the plateau incredibly stable).
Andre spent the afternoon refurbishing the two webcams that are mounted on the GTOWER. One of the webcams had icing problems last year, this has been fixed by increased the heat-flow over its transparent dome. The other webcam needed to be rotated slightly in azimuth so that we can clearly see the new South Pole station.
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The following three images were taken with the webcams on the GTOWER. The first one is a wide-angle shot of the AASTO, the second is a zoomed-in shot of the eagle-shaped ice-formation on the exhaust stack of the AASTO, and the third is black-and-white image of the GMOUNT with the AFOS and ADIMM telescopes. The zoomable webcam is particularly useful, since we can pan/tilt and zoom in by x12, all remotely via the internet. Follow this link for the latest images from the webcams.
We have been intrigued to monitor the development of the ice sculpture on the exhaust stack of the AASTO. The AASTO keeps warm by burning propane, and this process generates lots of water vapour, which leaves the AASTO via the exhaust stack at a temperature of about 60C. In certain conditions, the water can freeze and build up a remarkable pillar of ice. A new exhaust stack design was supposed to thwart the development of the pillar, but it hasn't worked quite as expected.
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Today was a very busy day solving various electronics/software problems.
Andre completed the installation of an internet-controllable mains switch. This will enable us to remotely power on/off various systems in the AASTO, and should reduce the need to bother the winterover technician.
The following image shows the inside of the entrance-way to the Dome (the smaller side passage leads to one of the arches). The entrance-way is constructed from hemi-cylindrical corrugated metal tubes, long since covered in a layer of ice.
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Just near the Dome entrance is a 2000-foot long tunnel chiseled through the ice. This was dug to allow passage between areas of the station when the outside conditions are bleak. It is very cold in the tunnel, about -58C, since at this depth below the surface the temperature remains at the yearly average.
The idea of being stuck halfway along a 2000-foot tunnel at -58C doesn't strike me as particularly appealing.
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Just for interest, here is a picture of the "Science" area where the computers are for public use. "Science" is in one of the big orange-coloured freezer boxes under the dome.
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Communication to the internet from the South Pole is only possible for about 8 hours a day, when various ex-geostationary satellites peek over the horizon. True geostationary satellites are not visible from the Pole, since they are just below the horizon. However, when such satellites reach the end of their useful life (usually due to running out of the fuel required to maintain their position) their rockets are given one last blast, which pushes the satellite away from the crowded geostationary orbit into one that can be seen from the South Pole for some hours per day.
This year our visit has coincided with the installation of a powerful new ground-station for the Marisat satellite, giving T1 performance to the South Pole for the first time. Here is a view of the antenna, about 1km from the Dome, orientated to catch the satellite as it skims over the horizon.
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After the usual stint at the AASTO working on our instruments, we took the opportunity to inspect the new station during an "open-day". The new station is normally off-limits, due to the on-going construction. The size of the new station is amazing: the part currently being completed is only one-quarter of the final building. The other amazing thing about the station is that it didn't exist three months ago - it has all been erected during the summer by the incredibly hard-working construction team.
About half of the 50 people wintering this year will be construction crew who will begin fitting out the inside of the new station. Unfortunately, not all the construction materials have arrived, and there is not enough time left to fly in all the material before the station closes. Priority is being given to food and medical gear.
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The new galley will be particularly impressive, with a bank of panoramic windows providing a magnificent view over the plateau. The new station is the highest structure at the Pole, apart from some aerials.
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When returning from the station tour, I persuaded our guide to show us the new power plant, currently being commissioned. The plant has three 750kW diesel generators, only one of which operates at a time. The generators are de-rated due to the combined effects of the altitude and running on JP-8 fuel (the same as used for all machinery, including the LC-130s, at the South Pole).
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While in a touring mode, I took the opportunity to pay a visit to the South Pole greenhouse. It is in an orange-coloured freezer box under the dome. You can see in the photo the ice deposits due to the humid air coming from the greenhouse.
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And here is the view from inside. Powerful lamps simulate the sun for a timed period each day. The plants look superb, and are highly prized during the long dark winter. There is a chair for people to relax and soak up the atmosphere. Apart from the sauna, this is the most humid location at the South Pole. The extreme dryness of the air at the pole makes for very dry skin.
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From the greenhouse it is a short walk through a tunnel to Skylab, a pleasant, warm, room overlooking the Dome and with a good view across the plateau.
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Andre relaxes after a hard day's work.
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In the evening we discovered that the crucial package of components has arrived from Sydney. We take it out to the AASTO, replace the mis-behaving board, and SUMMIT springs to life with all systems nominal.
Today is the first day that we have been able to relax for more than 30 minutes since arriving. All our experiments are operating, and our long list of tasks has been completed. In the afternoon we have "bag-drag" for the trip to McMurdo tomorrow. Unfortunately, we missed the snowmobile that had earlier visited the MAPO building to collect baggage, so Andre and I have to use a sled to pull about 60kg of stuff 1km back to the cargo area. The people who walk across Antarctica pulling sleds of 150kg or more are crazy. There is no other word for it.
The outside temperature dropped to -44C today, and is continuing to drop at about 1 degree per day as the sun slowly spirals towards the horizon. Once the temperature hits -50C, the LC-130 aircraft would be running outside their permitted envelope, i.e., no flights.
We spent an hour with Charlie Kaminski, the winterover technician who will be assisting with the AASTO experiments, and showed him how our experiments work, and the sort of problems that we might have during the year.
The evening gives me a chance to catch up on the diary entries.
Tomorrow at 9am we have a "re-deployment" meeting, followed by the 3 hour flight to McMurdo in the early afternoon. At McMurdo we will change planes (to a C-141 Starlifter) for the 5.5 hour flight to Christchurch, probably arriving early Tuesday morning. From previous experience, these flights are rather unpleasant. Still, it will be good to return to a place where you can walk around without ECW gear.
To bed at 6am (I was on a night shift), wake up at 8:40 just in time to get to the 9am meeting. Alexandra Brown gives us a pre-flight briefing and hands out certificates to prove that we were at the South Pole. She informs us that we will probably have a 5 hour delay in McMurdo. Groans all around.
There is time for one last visit to the AASTO (to install an array of infrared LEDs to allow us to use the webcameras during the long antarctic night) prior to assembling in front of the South Pole International PAX Terminal (a 3x3m solar-heated building) with 30 other people for the LC-130 flight to McMurdo. There are lots of tearful goodbyes exchanged between the outgoing passengers and the remaining winteroverers. After this flight there will be 111 people on the station. In two days time there will be 53, and thus it will remain until the first flight of the new season in October.
The flight to McMurdo's Willy Field is swift and pleasant. The temperature on the aircraft is about 0C, just right when you are sitting wearing ECW clothing.
The final approach to Willy Field takes 20 minutes, and is quite turbulent. This is due to white-out conditions which force the pilots to approach slowly and carefully. We disembark in the middle of a snow-storm; little wind, but lots of gently falling snow-flakes (such flakes are not seen at the Pole, where precipitation largely takes the form of "diamond-dust"). We pour out of the LC-130 and into one of two buses for the 45-min journey to the Pegasus runway where the C-141 Starlifter awaits us. The "road" to Pegasus is marked by flags at 10m intervals - if it wasn't for the flags, everything would be white.
Our driver informs us that due to the deteriorating conditions, the C-141 schedule has been brought forward, and we will be taking off within minutes. Also, the expected 160 passengers have been reduced to 80. There is much rejoicing on both counts.
There are, however, snatches of ominous messages on the bus's two-way radio that keep us edgy - "Pegasus base, we're worried about wing icing, can you send a crew out?" From experience we know that we could easily have to wait hours in a PAX terminal, spend a night (or, shudder, two) at McMurdo, or, as had happened a few days earlier, the C-141 could be turned around by mechanical failure after take-off.
We pull up briefly at a small building on stilts for a last minute toilet stop. For whatever reason, whether it was the temperature, the time-pressure, the swaying of the building caused by the queue of entering PAX, or the half-dozen people waiting impatiently directly behind me at the stalls, urination was elusive.
We rejoined the bus for the last 0.5km trip to the aircraft. I attempted to take a photo of the C-141, but we were being pushed along so quickly that there wasn't time. By a stroke of good luck, Andre, Paolo and I score seats that do not have another row of passengers directly in front of us. Is there no limit to our luck today? Will the weather close in? An aileron drop off? A hydraulic pump freeze? Surely something would go wrong?
Well, nothing did. We had tailwinds that reduced the flight-time by half an hour, and we landed in Christchurch after a smooth and comfortable flight 9 hours and 45 minutes after having left the South Pole, close to a record. Going from -44C and perpetual sunlight, to +20C and a balmy night was quite a shock. But a pleasant one.
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After clearing NZ customs, it was off to the Clothing Distribution Centre to return our ECW gear. Each item is checked off by the staff, and, if everything is accounted for, you receive a patch for your ski-parka labeled "US Antarctic Program". Americans are very good at patches, one of their many endearing qualities, almost compensating for the creation of Folgers coffee.
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After a miraculously painless trip to Christchurch, we disperse to our various hotels, and drain the hot water systems dry with long showers.
The adventure is over, and we will shortly return to UNSW to operate our experiments remotely for the next nine months.
As I concluded at the end of my last antarctic diary, the future of astronomy in Antarctica looks bright indeed.
Last updated 19-Feb-2001.
The Illustrated South Pole Diaries 2001 Michael Ashley mcba@newt.phys.unsw.edu.au