This week at Mawson 19 December 2008
The Horseshow Harbour Iceberg
One of the reasons Mawson Station was built at this site (in 1954), is that it has a very nice sheltered harbour in a horseshoe shape, known, fortuitously, as "Horseshoe Harbour".
In 1980, an iceberg floated into Horseshoe Harbour and became lodged there, and when the sea froze at the end of summer, it was stuck there for the winter. This had obvious implications for the re-supply ship Nella Dan the next summer, particularly because the fuel is pumped ashore via a long hose.
Once summer came around and the sea ice thawed, they made several attempts to move it, lassooing it and winching it to one side, even dynamiting it (a big bang, a puff of smoke and a shower of ice leaving a charred divot the size of a bathtub). When the currents shifted it to one side one day, they tethered it there until the resupply ship had been through, festooned with various ropes.
Eventually the thing just left one night, to be rediscovered 200km along the coast months later, still nicely wrapped-up in ropes.
Last year, it happened again. In March, just before resupply, a little berg that had been sitting in East Harbour since breaking off the glacier there a year or two before, drifted through Horseshoe Harbour and then got stuck right in the middle of the mouth where it has been frozen ever since.
This Week at Mawson spoke to a local expert on what he thinks will happen to the berg this summer.
Andrew "Buckshot" W, Meterological Observer
"Well, I spend most of my day over in the Met Building, just observing things really, and I have had a pretty good view of the berg from my observation room. From what I can see, if the side of it there, just sort of caves away, then the whole thing will just tip up like this and be on its way. I'd say about the third week of January"
Some interesting calculations.
From our in-house aficionado of this kind of thing…
The Horseshoe Harbour iceberg weighs about 20,000 tonnes. This is enough water to fill 5,000 brand-new water tanks across Brisbane, thus attracting over $8 million in water tank subsidies from the government. However, the rebate expires on December 30 and it is unlikely that we could get the iceberg to Brisbane by then, because it is stuck in Horseshoe Harbour.
On the Penguin Front
Over on Bechervaise Island, our intrepid Penguin Crew have been inviting penguins to take part in their exciting new electronic tagging study.
A total of 24 Adelies will be outfitted with teeny-weeny transmitters to help with the team's automated weighing station and tracking program, but the birds seem very reticent to take part.
"They don't appear to be very keen on the idea at first, but once we've glued it onto their back, they seem to quite like being part of such an exciting project. It's often like that with new technology in our own society, and penguins are no different".
Darren went on to say that the work, which involved sitting on a small stool for several hours while penguins would try to peck him, would have been "rather less uncomfortable" if he had brought a better stool or "maybe even just a cushion" with him for the day. They certainly do it hard over at Bechervaise island.
Meanwhile, back at Mawson
This week saw the commencement of the big yearly shutdown and maintenance of the main power generators, boilers & other important stuff. Nathan "Steamboat" S and Dave "Hotdog" G were two of the team on the ground in the Gen-shed. Nathan, a member of our important electron-management team, is instrumental in encouraging electrons to move out of the generators, and down the wires into the electrical boilers where Dave coaxes them into transitioning to alternate energy levels and so heat the water.
The final instalment of cargo from Davis arrived on Tuesday via the CASA aircraft, which landed on the sea-ice a short way from Mawson.
In order to have some fresh herbs, vegetables and fruit, we have a small one-room hydroponics shed made from 2 shipping containers. Lit by orange light, with electronically controlled pumps, and running at 25 degrees and 70% humidity, we have tomatoes, basil, lettuce, bok choy and some strange zucchini like object that This Week at Mawson was unable to identify.
Kevin "Gunny" G seems to be the main man to take on this important role, with interest shown from several others to assist with the daily tasks of stepping into the tropics to do some gardening.
Field Training with Hully
This Week At Mawson went out on location this week for one of the two training trips, cuningly timed to coincide with a blizzard. Dreams of extravagant views and early-morning strolls across mountaintops were tragically unfulfilled, to be replaced by being trapped for a thrilling 36 hours in the famed Rumdoodle Hut until the weather improved.
Matt (Comms Tech) , Jasmine (Chef) & Andrew (Met Observer) however, set out Monday morning in fine weather and with more forecast, thanks to Andrew, who just kept observing better weather as each day went by.
"I have to admit", said Andrew "Buckshot" W today by radio from Fang Hut, "I really do know good weather when I see it."
It's not just penguins and ice when it comes to science at Mawson, there are a number of physics experiments that have been running for years but which still need maintenance and the occasional upgrade. One of these is the geophysics measurements of the Earth's constantly fluctuating magnetic field. There are two buildings dedicated to these tasks, a nice new yellow one and a quaint archaic old one called the "Magnetic Absolute Hut".
The newer one houses several highly-senstive automated devices of bafflingly obscure design which require a personal touch for validation purposes each week, by none other than "Tubby" G, who ventures into this building each week to line things up and take readings.
In the other hut – the "Absolute Hut" - certain points need to be sighted from a distance and angles measured in a rather special way with an inclinometer, which Tubby does once a week.
And then there is COSRAY.
The cosmic ray detection lab houses two detectors, one to detect neutrons and another to detect muons. It also, this summer, houses Bob S and Barry O who are upgrading the muon detectors – the big metal tubes which contain various clever electronics. More on that next issue.
The big white plastic things are the neutron detectors. The white plastic is polythene, which slows the neutrons down, under them is a big chunk of lead which slows them further so that they are slow enough to interact with the boron gas in tube placed right in the middle, ionising the boron gas, which can therefore be counted by clever electronics.
And last of all
You may be wondering how the station coped while our chef Jasmine was away for three days on field training – well Dieso Aaron F was well up to the task on Tuesday night with a range of gourmet pizzas in attractive colours, with the assistance of Ben S who chopped up the chillies.
That's it for TWAM for this week, but in our NEXT EXCITING ISSUE, we will not only have numerous full-colour pictures of an Icy Christmas, but also an IN DEPTH review of what your transport options are at Mawson Station.