Wednesday, August 02, 2006

Cabaret, Super Hero night, Still alive after Midwinter -its also getting lighter - AIS explanation

The rest of midwinter was just as tiring as the first half but instead of making presents there was frantic preparations for cabaret night and the photo competition.

The photo competition run by Anto over midwinter. Really amazing photos, which took ages to vote for. Posted by Picasa

The photo competition was hotly contested there were five categories: People, Environment, Wildlife, Abstract and Bob (pictures people had taken of themselves). Everyone entered at least one photo and most people entered one for every category. Since we have all done pretty much the same things we all had very similar photos so judging was harder than expected. I got second prize in the people competition with a picture of Jacko the RAF mast officer taken at the top of the 45 m masts. All the photos were great and all of them are going to be made into a collage.

The next big event was the cabaret. As usual with these sorts of things there are the people who can play instruments and sing and do everything and then there are the rest of us who just have to make fools of ourselves. Most acts were put together on the last day but the seemed to work.
It was a great night and inspired the formation of the Halley band which now meets on friday evenings (because all other evenings are taken up with other things).


One of the highlights of the cabaret was Liz cutting Andy in half. Liz couldn't help laughing hysterically the whole time which just so funny. Posted by Picasa


Bob, Liz and Chris start the meaning of life song just before Brian walks in. Really really good. Posted by Picasa


The Samba band runs through its paces, so much fun. Posted by Picasa

The cabaret was just about the last thing that happened at midwinter and I think most people were fairly glad to get back to the normal routine of work after a week of lazing about and getting fat, you have to draw parallels with christmas again. Apparently the danger after midwinter is that you get depressed because its still dark and you don't have anything to look forward to for a month or two. I didn't find this at all mainly because I was incredibly busy. I know that I have kept on saying that I would have more time after midwinter to keep the blog up-to-date and that I would have more time to do my stuff but that doesn't seem to have happened.

One thing I mentioned last time was the fact that we have had unusually high snow accumulation this year (maybe a consequence of global warming). This has mean that we have had to raise equipment out of the snow. I have more to do than most people because I am the winter mast officer which means I am in charge of making sure all the masts are nice and straight and not over tensioned etc... One of the jobs that I have spent a lot of time doing is raising turnbuckles. Turnbuckles are the attachments that have a right handed thread at one end and a left handed thread a the other and are used to tension stays. I have done quite a lot of this with Dave the Comm's manager since the Comms masts seem to be buried more and he has catalogued the process in his blog here. I like to think that he was taking photos while I was doing all the work but thats not true. I have probably raised about 30 stays so far and have about 10 more to do. My main responsibility, the AIS radar, has been behaving itself so I have started some winter projects. These are some programming to extend the AIS radar's range and some hardware design to make a cloudmonitor. It keeps me busy when the weather isn't very nice outside.

After two weeks of recovering from midwinter and digging in the snow we had a Super Hero's night. We preceeded this by watching the Incredibles in the afternoon.


Halley super heros. from left to right: Dave as Super Calf, Brian as Super Mario, Vicky as Electra, Nicola as Popeye, Kirsty as Haribo Girl, Fran as Caslab Girl, Liz as Super Gash, Mark as the Incredible Hulk, Alex as Batman, Andy as Bicycle Repair Man, John as Zorro, Simon as Thor. In the front we have Chris as Spider Man, Bob as Fat Man and me tucked in behind Chris as Kite Boy (special power making lots of wind). Posted by Picasa


Mark was a bit too scary, and I think the showers are still a bit green. Posted by Picasa

The night was really good fun. After dinner the main corridor was cleared of dangerous items and a few people had a go at bar-room-bungie. Here you put a harness on and attach a bungie to you back. You then run down the corridor as far as you can until you are suddenly pulled back by the bungie. At this moment you slam you hand down and stick a postit to the ground marking how far you got. This happened a few times until unfortunately the attachment between the bungie and the harness snapped and the bungie flew down the corridor and hit Bob on the leg. Luckily he wasn't too badly hurt but he was in pain. That put a bit of a dampener on the evening but it was still a good night.

The sun is slowly returning as expected after midwinter, so the base is getting ready for the post-winter trips that start at the beginning of September and last 10 days. On this trip we get to choose where we go. We seem to be sticking to the same teams which makes sense. The ones who went first (us) will go first so we had it the warmest last time and this time will have it the coldest. I think we are planning on exploring the rumples a bit. Before those trips we are going to have some penguin trips to the local emporer penguin colony at Windy Cove. Kirsty and I saw them from the top of the cliffs before midwinter here. This time we will be going in larger groups with Simon the GA and will abseil down to the sea-ice and I am told that the penguins come up to within a metre or so of you. It should be awesome. Once we are on the sea ice we have to get off it by jumarring back up. In anticipation of this we have been abseiling and jumarring back up off the Simpson platform.


The light is slowly returning. Sun-up is due on the 10th of August. We have already started kiting again, which was awesome as usual, but I haven't got any photos because I have been too busy kiting. I did get this photo of the memorial (to those who have died at Halley) when I went searching for it after reports that it had disappeared in the snow. The little blip on the left on the horizon is Wonky Caboose. Posted by Picasa

It getting light enough to kite as well, so now half the people on base are watching the wind speed for that perfect wind. Even though it is getting light its still pretty cold. Although it hasn't got below -50 degrees C (it hit about -48 degrees before midwinter) its sometimes below -40. When it started to approach -40 again about a week ago, Kirsty and Vicky ran outside with damp hair and let it freeze with their heads hanging down. That didn't work so well so they go a tub of warmish water and dunked their hair in it and then let it freeze (about 40 seconds) and then stood up.


Kirsty shows off her frozen hair. How cool is that. Photo courtesy of Dave Posted by Picasa


Vicky's wild woman impression. Photo courtesy of Dave Posted by Picasa

Another job we have been doing is helping build a Nansen sledge these are usually made by Snowsled, but we made ours out of spare bits.


Liz, me and Nicola working on the Nansen sledge, in the garage, that the whole base helped build out of spares. Its pretty amazing that we use these sledges made of ash, lashed together with leather and twine. So we had to learn to square lash and fettle all these wooden bits to make a fully working sledge. Photo courtesy of AntoPosted by Picasa

We've also had the return of the aurorae. Now for the science bit well and a bit to explain what I do. You might have gathered that I am the AIS (Advanced Ionospheric Sounder) engineer. The AIS is a radar that bounces low-medium (0.1-30MHz) radio waves of the ionosphere. The ionosphere is a charged region of the atmosphere (between about 100km and 800km up). These ions, charged particles, are created mainly by intense ultra-violet light and at low altitudes would just recombine with an oppositely charged particle. At high altitudes there aren't enought atoms or ions to do this so there is this charged region just sitting there. Radio waves bounce (actually they refract since the charge density changes with altitude) off the ions but the altitude that they do this depends on the frequency of the radio waves. So the AIS in it most basic sounding mode just sends pulse trains up at different frequencies and from this you get a picture of the ionosphere.

What is the point of all this?

Its all to do with space weather and how the Sun interacts with the Earth. The Sun is constantly sending out streams of particles which fly off and hit the Earth, or they would but the Earth's electromagnetic field protects us by deflecting these particles. The magnetic field is itself deflected out behind the earth into a long tail. Occasionally you get a coronal mass ejection where you get a flare on the sun and loads a particles are flung out of the sun. The Earth's electromagnetic field gets hit pretty hard and wobbles. Consequences of this are that satelites get knocked out and I think the North American electricity grid was knocked out by a big flare. Another consequence is that the charged particles get tunnelled by the magnetic field lines and dumped into the polar regions and you get aurora. The ionosphere gets affected by all this. You can see that if the magnetic field is fluctuating then the charged ionosphere is going to move about. The AIS is build here because Halley is near the auroral zone and it is one way of working out how the Sun affects us.

Anyway we had some aurorae. Now auroral activity is linked to the activity of the sun. The activity of the sun can be measured by looking at the number of sun spots on the sun's surface. The sun spots go through an 11 year cycle and from solar maximum to solar minimum and back to maximum. The last solar maximum was in the year 2000 so this year should be a solar minimum year. So we don't expect that many aurora. We have only seen about 3 good ones. The main problem being that you have to have good weather at the same time. There have been quite a few times when we can see on the magnetometers that there is something spectacular going on with the magnetic field but haven't been able to see anything because there is a blow on at the same time. And then there is the moon, incredibly bright to our sun deprived eyes. I could go on ...

It amazing when it is clear.

The Halley sign post, with a faint aurora in the background. Posted by Picasa


A slightly more impressive aurora taken from the Laws looking towards the Piggott. Posted by Picasa


My most recent "hair" picture. I'm trying to take a picture of myself in the same place everyday and will hopefully make a movie of my hair growing. I do look a bit disgusting. Posted by Picasa

Hopefully next entry will be soon and include photos from our first penguin trips down onto the sea-ice.

7 comments:

Anonymous said...

You look like Trumpkin, the evil, then good dwarf in Prince Caspian.
Heaps of love, the bride of Mao xxxx

Anonymous said...

http://www.inarnia.net/obrv/Trumpkin.jpg

Will said...

good god Juli, you look like some kind of deranged evil Santa, hidden away at the South Pole commanding a gang of wicked elves to make dangerous toys with which to punish all of humanity.

Anonymous said...

I agree with the Santa comparison.

Geoff_W said...

So how does the refraction work ... I'm thinking that the ions will re-radiate the radio waves in a frequency-dependent pattern, does this pattern not have spherical symmetry?? And if the emitter and receiver are in the same place, it can't be like a mirage-type refraction effect can it?
Also, what is the magnitude of the magnetic field fluctuations with respect to the long term stable field of the earth? Does the fluctuations change the sign, and is this historically evident in magnetic magmas? Is it the kind of thing that could cause pigeons to go crazy or kill people with pacemakers?

Angie said...

What a Hair do!

Reg said...

Hi: Anyone down there a radio ham?
Would LOVE to contact Halley on ham radio. No problem contacting the hams at Rothera, but never heard anyone on from Halley.