South Pole Diaries 2000/01



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.

John Storey with telescope at Dome CWe 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.