Professor Michael Ashley is currently in Antarctica to deploy a telescope to one of the most remote locations on Earth – a place known as Ridge A, some 850km from the South Pole.
This is the fourth instalment in Professor Ashley’s Antarctica Diaries. To read the previous instalments, follow the links at the bottom of this article.
January 2 – Umbilical cable connected
I learned an interesting statistic: the cost of keeping a person here at the US South Pole Station is about the same as supporting someone in an intensive care unit. So we are indeed privileged that our science project has been rated highly enough to warrant this support.
Today was a significant milestone for our experimental work. We connected the “umbilical cable” that joins our Engine Module to our Instrument Module.
I should explain. The telescope we are deploying requires about 200 watts of continuous power to run. During the summer months, this can be easily provided by solar panels, but during the long winter months we rely on two small diesel engines running from jet fuel. The engines are in the Engine Module, naturally enough. The 70-metre-long umbilical cable routes the power from the Engine Module to where it is needed in the Instrument Module.
The physical separation between the two modules is needed to avoid water vapour from the diesel engines interfering with the astronomical observations (and covering our telescope in snow).
Meanwhile, work on the telescope continues apace, and Craig, Abram, and David (fellow researchers from the University of Arizona) decide the new cryostat is working sufficiently well that they can dismantle the old prototype detector, and move across to the new system.
January 3 – Tour of the Askaryan Radio Array
We awake this morning to a beautiful sunny day with almost no wind. The various flags around the station are hanging limp. These conditions are superb for getting work done outside. Even though it is nudging -30ºC, the lack of wind makes it very easy to stay out for extended periods.
Ridge A has much lower average wind speeds than South Pole, since it is very close to where the katabatic (downhill) winds originate on the Antarctic Plateau. The further you get away from this high-point on the plateau, the windier it gets.
After dinner I am fortunate enough to have Kara Hoffman (University of Maryland) and Michael Duvernois (University of Minnesota) give me a tour of the Askaryan Radio Array (ARA).
The aim of this project is to detect extremely high-energy “cosmic rays”. These are atomic nuclei that are accelerated to astonishing energies by mechanisms that are still unknown. A single such particle can have as much energy as a thrown cricket ball.
To put that in perspective, if a tiny dust mote had the same speed as one of these nuclei, its kinetic energy would be tens-of-times greater than the largest hydrogen bomb ever tested.
The Askaryan Radio Array will eventually cover about 100 square kilometres close to the Pole, and is typically 100-200 metres below the ice. We visit the closest part of the array, some 3km from the station, and it gives me a small appreciation of what it must be like venturing out onto the Antarctic Plateau.
Normally we do all our work within a kilometre of the station, and there are always people and machinery in view. But out here at the ARA, there is a full 180º region where you look on to a featureless expanse of ice.
The ARA is actively researching ways of providing power to their array. Distributing electricity from the station’s megawatt diesel engines would be costly, so they are investigating whether solar and wind power will meet their needs. It all hinges on whether the wind generators can be made reliable enough to run unattended in the extreme winter conditions.
The data from the ARA antennas are all sent back to the Ice Cube Laboratory. This building houses the data processing and electronics for the Ice Cube experiment – more than 5,000 photomultiplier tubes buried up to 2.4km deep in the ice, searching for neutrino sources in the universe.
January 4 – Bicycling at the Pole
There are lots of different ways of getting around at the South Pole. Most people walk, but a few ski, and a very few use a bicycle with special snow tires (see photo at the top of this article). Some years ago when I was here, a chap brought a unicycle with him, and used it to set a record for the first person to unicycle around all 360º of longitude.
Apart from the usual work on our instrumentation, today was marked by the erection of a meteorological mast that we will be fitting out with temperature and wind sensors and sending to Ridge A. Campbell and Luke (fellow researchers from UNSW) top the mast with a New Zealand All Blacks flag. The mast gets quite a bit of attention from people walking past.
Late in the evening I get an Iridium satellite call from Chinese collaborators of mine who have just arrived at Dome A after a gruelling three-week traverse from the Zhongshan Station on the Antarctic coast. While I am at the South Pole I will be in regular contact with the Chinese by Iridium phones and data links as they install a new PLATO module built by our team at the University of New South Wales.
January 5 – Skiing with a parasail
While walking out to the Martin A Pomerantz Observatory (MAPO) building this morning, I come across a very energetic person on skis, being pulled along by a parasail. He was cutting backwards and forwards across the wind, and being lifted more than a metre into the air at each turn. Wind-assisted skiing is definitely the way to travel across the Plateau. It looks very graceful and lots of fun, but is by no means easy.
Having completed the testing of the individual components, it is now time to put the Engine Module outside the Polar Haven to test the entire system. This takes most of the day (and will take some of tomorrow).
January 6 – We have main engine start
Just before dinner I venture on to the roof of the South Pole’s elevated building to locate a suitable access duct for an Iridium aerial. (I go under the close supervision of Al Baker – a senior manager at the South Pole Station – as the roof is normally a no-go area due to the risk of slipping over the edge.)
We can’t find a suitable duct, but we do find an Iridium aerial already mounted, and closer inspection inside the station reveals it is available for our use.
Having my own Iridium connection from the station will allow me to have continuous access to the internet, and from there I can log-in and control our experiment when it is deployed to Ridge A next week.
Immediately after dinner we hold a team meeting to discuss our progress to date and the work still to be done between now and leaving for Ridge A. Craig, Abram and David are making very solid progress on the telescope, and the UNSW team is happy with work on the engines and electronics.
After the meeting we are ready to run the engines. One of them starts nicely, but the other sounds rather sick and stops quite suddenly after just a few seconds of operating. We will have to take the engine out and examine it tomorrow.
January 7 – Engine disaster
Campbell and Luke spend this morning pulling the misbehaving engine out of the Engine Module and bringing it back inside the Polar Haven for testing.
After lunch the true horror of the situation is revealed: the engine has bent both its push rods and broken the rocker that activates the intake valve. We speculate that the exhaust valve may have stuck closed, perhaps related to the cold temperatures. That said, the engine should have been at around -10ºC, which is not an unreasonable temperature.
While there is no chance of repairing the engine before leaving for Ridge A next week, we fortunately have a spare one with us for just this kind of eventuality. Campbell and Luke labour long into the “night” (it’s light here 24 hours a day) to swap it in. Meanwhile, Yael (a fellow researcher from UNSW) is working hard on the cabling for a 15-metre meteorological mast that will sit next to our experiment.
Being Saturday, the chefs have a break and the meals are prepared by various groups of mechanics, scientists, managers and so on. You never know what you might get. Today the food is really very good, with excellent pizzas.
This evening is the annual South Pole Meteorological Wine and Cheese Party. For a moment I feel guilty sipping wine for an hour while Campbell and Luke are struggling with the diesel engines … but only for a moment. About 60 or so people attend the party, and it makes for a most enjoyable time. I met this year’s winterover station manager, Katie, who has wintered twice before.
I heard an interesting story of a vodka-fueled party, that occurred at Vostok Station in April 1980. Some hours after the party finished the station’s diesel engine plant burned down. This would normally have meant almost certain death for the station crew, if it hadn’t been for their extreme resourcefulness in the manufacturing of fuel heaters, and digging out and repairing old abandoned generators to restore the electricity supply.
January 8 – Elvis turns 77
Today would have been Elvis' 77th birthday, so we celebrate by having an Elvis-themed Sunday brunch.
Yesterday’s transplant of the spare diesel engine has worked well, and we now have a fully functional Engine Module ready for thermal testing.
We turn our attention to the Instrument Module, which is now essentially in a complete state, just undergoing final testing and software tweaks.
The University of Arizona team are working very long hours to finalise the telescope detector system, and so far everything is going smoothly.
The telescope is called HEAT – High Elevation Antarctic Telescope – and is quite unlike any telescope you would have seen before. Instead of taking optical images like a traditional telescope, HEAT observes terahertz radiation – between the infrared and radio parts of the electromagnetic spectrum.
Not much is known about what the universe looks like when observed with a terahertz telescope. This is because the earth’s atmosphere is so opaque to this radiation that essentially nothing reaches the ground from space.
Except, that is, at Ridge A, and the surrounding few-hundred kilometres on the Antarctic Plateau. Here the water vapour content of the air is so low that the terahertz radiation from astronomical objects can reach the ground. There are good theoretical reasons to believe we will learn a great deal about how stars are formed through terahertz observations of the cocoons of molecular gas from which the stars evolve.
At 8pm Craig and I give a South Pole weekly science lecture on HEAT and PLATO-R.
Further instalments in Michael Ashley’s Antarctica Diaries will appear on The Conversation in the coming weeks.
Follow the links below to read the previous instalments: