South Pole Diaries 1993/94



7th February 1994

From Michael Burton.....

Well all being well this should be my last South Pole report for this summer; I'm due to fly out of here at 1pm today, and its 9:30am right now. It's been a memorable two weeks, and to tell the truth civilisation seems like a dream to me right now. The snow and ice and cold is reality! It's been remarkably successful time, not just for our experiments, but for all CARA's experiments and team. There will undoubtedly be problems over winter, of technical, physical and psychological nature, but Antarctic astronomy has made a major step forward this summer and spirits are high. The practical demonstration of the concept is virtually upon us!

I've left the IRPS in good shape; there are some teething difficulties but they are easily monitored and fixed by spinning various wheels one more time. There are some minor software bugs, but these are amenable to mcba sending patches over the network. (Actually the first test of the real time internet is being made at this minute - which should give us an extra 9600 baud for 3 hours a day, compared to the 1200 baud we have for 5 hours right now. And there is the potential promise of a NOAA weather satellite with considerably greater rates). I've taken a little data, but there is limited science to be obtained in daylight observing, and I have had to be content with daylight scans of the CVF. Even at M small changes in the thermal flux as the Sun moves around dominate over any sky fluctuation noise.

The microthermals are not in quite so good shape. The experiment is up and running, but we have discovered an interesting phenomenon; growth of ice crystals on the filaments. The higher up the mast you go the more prevalent is this growth; a sensor left of the roof of the Clean Air building shows moderate growth and those 85ft are absolutely covered. There clearly is some kind of critical size of filament or fibre on which crystals grow, as if there is a nucleation size. The larger cables and even the supports for the filaments don't show any ice growth for instance. And there is no ice growth on the roof of the Astro building. Some more experiments needs to be done, and it's possible that by sending a current through the sensors directly we may be able to melt the crystals for time periods long enough to take sensible data. But we need to do some consulting with the experts first!

So I'm going to sign off for what is probably the last time before I get to Australia. Unless my flight is turned back - the weather is deteriorating a little at the moment, or I get stuck in Mactown waiting for a flight out. Then you may get to here what life in an Antarctic coastal town is like. So at 40 below for the last time, cheers!

And wish John Briggs luck over the winter. Our data depends on him! (Good wishes to be emailed to jbriggs at the Pole.)