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| South Pole Diaries 2000/01 |
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Wednesday
6th December 2000
From
John Storey.....
We spent the morning learning more
about the rotator, and contemplating observing scripts for
Summit. After lunch we moved on to the final assembly of Summit,
which proved to be remarkably challenging. I will not bore
readers with the technical details of which parts fitted and
which bits didn't, nor will I indulge in graphic descriptions
of just how horrible silicone heat-sink compound is when it's
smeared over everything. We were very grateful to have such
an excellent lab space to do it in, it would not have been
much fun in a tent.
 We
even found a fork-lift! It was actually sitting at the end
of our lab, cunningly disguised as, well, a fork-lift. We
had of course noticed it but decided it was unsuitable because
all its things were in the wrong place. (I'm sure there are
some specific technical terms for the various "things"
that fork-lifts have on them, like forks, bit that holds the
forks, legs, little wheels, and sticking-out-bits that stop
it falling over. Suffice to say these were all in the wrong
place.) Anyway, it turned out they were all adjustable and
so now we have a fully customised fork-lift better adapted
to our purpose than anything we could have dreamt of. As I
type, the Summit instrument is poised 2 metres above the ground
waiting to be lowered onto the Summit electronics rack.
Here at Dome C we are some 1700 km
away from the South Pole, or 15 degrees. At this time of year
the sun never sets, but at midnight dips to within 8 degrees
of the horizon, rising to about 40 degrees elevation at noon.
There causes a significant diurnal temperature variation,
from a high of nearly -25 C at midday to well below -40 C
at midnight. On some days there's quite a bit of low-level
haze, and on other occasions it's more generally overcast.
But most of the time it's just a crystal clear blue sky from
horizon to horizon.
It is very striking just how low the
wind speed is here. It hasn't been more than a couple of knots
the whole time we have been here, and it's always from exactly
the same direction.
Speaking of which, this afternoon Luigi
led us on a tour of the wind generator and energy storage
facility. This is still at the experimental stage. A 5 kW
wind generator has been modified for the low wind conditions
by changing the blade pitch angle and replacing the gear-box
driven alternator with a direct-drive high efficiency unit.
Several metres below the ground a well-insulated shipping
container holds a bank of lead-acid batteries and two large
cylinders of glycol. The latter act as thermal storage---any
excess energy from the wind generator is used to keep the
chamber warm. This is where we will place Icecam, which will
arrive at Dome C around Christmas.
Tonight's dinner featured home-made
yoghurt with a variety of liquers available to jolly it up.
The glazed pear tart wasn't bad, either.
John
 
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