Monday 11th January - Ice Halos

From John Storey.....

Today we saw the most spectacular ice halo imaginable. All the ones I'd seen previously, and even been moved to write a paper about with Max, paled into insignificance. We got the full treatment - 22 and 46 degree haloes, sun dogs, a horizontal arc that went the full 360 degrees, a brilliant circumzenuthal arc, 120 degree spots, that funny football shaped thingy on top of the 46 degree arc, a cross 180 degrees from the sun, and some funny white arcs that completed the circumzenuthal arc but I'm sure weren't supposed to be here. The whole station went berserk with people firing off rolls of film. I tried to grab some images on the webcam by using a flag as an occulting disc, but not very successfully. There are some excellent photos and a description on the web page (http://www.spole.gov). This may be the best halo display ever recorded on film.

A little previously I had a go at bringing the Orbcomm satellite communication system up. When I came to plug the transceiver into the serial port on the general purpose PC, I found the serial connector was sort of dangling loose inside the machine so I had to take the whole computer apart. I was just musing to myself about this interesting interpretation of "plug and play" (sort of "find the screwdriver, dismantle, lash things together, and then play") and speculating out loud about how I could contrive a gruesome end for Bill Gates when in walked the two ASA psychologists. They said they just wanted a look inside the AASTO, but I'm sure they'd been tipped off. I tried to put on my best "I really do like Windows 95" expression but I think they know.

Anyway, believe it or it or not the Orbcomm box is alive and claims to be looking out for passing satellites, but it hasn't actually found one yet. Andre - is there an ephemeris somewhere? How many satellites are up there that I can talk to? Also, is that eggbeater antenna really 50 ohms?

Last night, Fred Mrozek, Peter Gillingham and I brought the whole top-end spider of SPIREX inside, put a plastic bag over the secondary to minimize condensation, and plugged the PZTs into the driver electronics to stop them arcing over as the unit warmed up.

We then confirmed Mick's diagnosis that PZT #3 is stuffed. We swapped cables around and made sure it was actually the PZT itself. Actually the strain gauge works, but not the PZT itself.

While fiddling about the whole thing suddenly stopped working. We decided it was a fuse and tried to dismantle the box to replace it. This was a totally baffling experience and I must have wasted 45 minutes undoing unimportant screws and pulling back promising looking rubber strips. If it wasn't for the fact that one of the world's top opto-mechanical engineers was working with me and was equally baffled I would have felt very silly.

I finally prized off the black plastic bit on the mains inlet and there sat not one but two fuses. The manual says 1.6 A slow blow so we stuck in a couple of 2.0 A slow blows which is ok if you don't worry too much about significant figures.

So then all the lights worked again, but when we plugged in the new PZT it didn't work. Arrggghhh! Not to put too fine a point on it, the strain gauge bridge that provides position feedback wouldn't balance.

At 2 am we gave up and went to bed.

Today we puzzled over the possible reasons why a brand new PZT strain gauge might not balance. The book says just to twiddle the front panel "zero" knob, but that simply didn't work. Ripping the plug-in circuit board out and examining it, it seems there are two amplifier stages. The front panel "zero" pot works on the second stage, and there is a second, internal zero pot, P2, on the first stage. Aha! So if the first stage is too far out of whack it will saturate and adjusting the second stage won't help. So, trim P2 and we're in business. P2 was at 19 turns from the CCW stop. However, turning it this way and that had remarkably little effect. Do you think there's any chance of scoring a circuit diagram out of PI?

The new bridge is 700/701 ohm, compared to the previous unit which is 706/707 ohms, ie a 1% difference. A drawing of the strain gauge assembly shows that both bridge elements measure the same thing, ie it's not differential. It's therefore the absolute value that matters, not the difference. Since the new strain gauge is 1% lower in resistance than the old one, we figured that reducing the other two resistors in the bridge (which are on the circuit board) by the same amount might just work.

Sure enough, a couple of 75K resistors in parallel with the existing 705 ohm resistors (which are described in the book as 703 ohm) and bingo! - a nicely balanced bridge.

I'm not sure what kind of resistors I used but they were blue and looked very expensive and have written on them: BET RN60D 7502FJ NA60.

I put P2 in middle of its travel, for want of a better idea, and adjusted the front "Zero" pot as per the manual.

Tonight we'll take the secondary mirror assembly apart and put the new PZT in. This evening I've just received some very helpful emails from mcba, Thomas and John McMahon which I think answer just about everything, so I'll make great progress tomorrow.

Al Fowler turned on Abu's closed cycle cooler and it went ker-chug ker-chug all day but is not cooling down the system fast enough. Al is now convinced that the cooler head is stuffed and is waiting for Al Harper to bring a new one in.

A major problem is looming with the flight schedule, in that they plan to close all flights between McMurdo and ChCh from 18 Jan until 26th, while they shift the airfield onto the ice runway.

My only other activity today was to make a nice gangway across to the AASTO from the snow. Until now you've add to fall down the bottom of a snow drift, pick yourself up and then climb up the ladder. The new method conserves gravitational potential energy and reduces the risk of breaking a limb. I also tidied up around the AASTO and straightened the thermometer so it looks nice on the webcam.

John

Tuesday 12th January - Mostly Bad

From John Storey.....

Most of today's news is not good.

Last night we had a meeting to discuss the PZT assembly behind the secondary mirror. Although we were initially quite proud of our design, Peter and Fred were able to point out some rather serious problems with it. First, the length of the aluminum rods on the end of the PZTs means that the weight of the mirror creates a bending moment on the PZT when the telescope is tipped. Secondly, the balls at the end of these rods are forced to slide across stainless steel grooves. Thirdly, because the backing plate is made of aluminium, rather than Invar (our original Invar one was the wrong shape), there will be a substantial sliding motion required. All this is in addition to the lateral load that we are placing on the PZTs through the weight of the mirror. In effect, the mounting almost *required* one PZT to break in order to accommodate the thermal contraction.

We decided the best thing was to machine grooves into the end of the aluminium rods, allowing the balls to roll rather than slide. (IRIS II at the AAT uses a similar system.) It was in disassembling one of the PZTs to do this machining that we broke it.

If we can't get a replacement we will instal the dummy PZT, and basically be back where we were 2 months ago.

The Abu cryo-cooler is still going ker-chug ker-chug, but to little effect. Al Harper is bringing in a new cold-head: it will take a week to instal and test. If it doesn't succeed in bringing the temperature down we will have little choice but to cancel the whole project.

A final piece of sad news: Walter Wild, an adaptive optics expert and astronomer from the University of Chicago, died yesterday of a heart attack, aged 44.

Last night the mail spooler (or name resolver or whatever) of magnolia got jammed, meaning that none of my mail went in or out. Victoria the unix she-guru fixed it this morning just before the satellite set, and there was a rash of messages transferred but not, I think, all.

Thanks to some very helpful messages from mcba, jfm, Mick, Andre and especially Thomas, we've solved most of the minor problems we were facing.

While I think of it, the last team here clearly made a big impression on the station. I'm often being asked (mainly by the women), "where's Mick, where's Andre, where's John?" (or, "where's that big hairy guy, where's that cute eskimo, and where's that Australian guy with the American accent?) and I have to confess they've scattered to the four corners of the earth.

Having got to bed late last night after picking up bits of broken PZT from the floor, I was awoken again at around six by a D7 bulldozer just outside my tent. Apparently they'd decided to rearrange the snow. Given that Antarctica is twice the size of Australia and is mostly snow, they had plenty to choose from and I cannot see why they couldn't have gone and rearranged some other bit. I guess I wasn't in a very good mood anyway.

Then they decided to fix the Rodriguez well that supplies water to the station, using waste heat from the diesel generators to melt snow. This meant we went into water conserving mode, which means paper plates and plastic cutlery in the dining room, just like being on a picnic.

The psychologists are continuing to watch my efforts to grow to love Windows 95. My attempts to actually print something today came to nought. Maybe I shouldn't have disconnected myself from the Microsoft Network by turning off the Microsoft Netware tool that was insisting I impersonate someone else so I could log into a Microsoft mail-server. As soon as I find the Windows 95 CD I'm back in business.

The good news is that, with jfm's help, I've found out what the other mouse buttons do! Namely, middle button: nothing; right-hand button: bring up a menu to change the screen colour. Hey, this is great, Bill! It's really useful having that on a mouse button! I like to change my screen colour every 5 minutes; much more often than I want to, say, print things. Oops, the shrinks are writing stuff down in their notebooks again...

The really funny thing is that *everyone* from PI AG (Deutschland) to Mick to various people's kids sent messages saying: "of course the bridge won't balance unless you include the extension lead, which has about 5 ohms resistance". Well yes of course I know that (now) and so I've taken the resistors out of the strain-gauge preamp while no-one was looking and it works perfectly and it's probably Ant's fault anyway.

The good news today was that Michael Burton, Daniel and Matt arrived this afternoon, along with the sodar. The sodar has been uncrated and looks good; the sodarmites also appear to be in good shape and ready for some hard work.

I've had no success with the Orbcomm. It's all wired up and claims to have spent the last 4 hours looking for a satellite. I've suggested to it that it try looking in the sky, rather than underneath buildings or hidden behind bulldozers but, even with this helpful advice, it's having no luck. I've now taken Andre's "short big" antenna and lashed it to a flag pole. This brings it 3 metres closer to any passing satellite than it was before, which might help.

Tonight there are a couple of talks by a team of French and a team of Dutch folk who are skiing their way across Antarctica. I've decided to give the talk a miss partly because I want to get on with doing stuff, and also I find it hard to fathom why anyone would want to ski across Antarctica when it's already been done. Particularly bizarre are those folk who choose to walk, when skiing is a lot easier and being towed behind a parafoil easier still. If you're going to be cold and miserable for 6 weeks why not just lock yourself in a meat freezer and listen to Spice Girls tapes. I look forward to meeting the first group to roller-blade across the continent dressed only in board shorts, T-shirts and back-to-front baseball caps.

John

Wednesday 13th January

From John Storey.....

This morning we put Jessica's nylon snow cover on the sodar antenna, attached all the little springs that hold it down, and spent a couple of hours taping up all the little holes where ice crystals might get in. It now looks exceeding smart with aluminium tape everywhere and the handsome colour-coordinated silver nylon cover. Webcam devotees will already have noted that the antenna is now installed in pride of place on the roof of the AASTO, just to the right of the entrance door. (By the way, "sodar" stands for sonic radar. The data reduction package is called SOD_IT. Or at least, if it's not, it should be.)

Lurking under that shiny cover are 52 piezoelectric transducers (the infamous "hooters") that can generate a sound level of 87dB 200metres away. Fortunately the beams are sent straight up or 30 degrees from the zenith. The sidelobes that come out horizontally at ground level are 40dB down, which is still loud but not offensive. It can't be heard inside the MAPO or ASTRO buildings, and is *just* audible from the cargo area in front of the Dome. However, it is a tad noisy *inside* the AASTO...

By early afternoon we had it merrily beeping, singing its little heart out with the sodar song. We seem to be measuring to 600 metres altitude without any problems, which is just beaut. It's also hooked up to the supervisor computer via port 2006. We can talk to it via telnet, but have the "Narrabri" problem that the frog-DOS wants to interpret the RS232 bytes in its own peculiar way. Daniel says that mcba can fix this particular problem in a flash, and possibly already has in a pharlap script somewhere. We await instructions.

It looks like the simplest thing is to leave the sodar powered up the whole time. The noise could then be turned on and off via a cron script on pharlap. The only disadvantage of this is that the hard disc on the IBM laptop will be running continuously. I confess to not having gotten around to designing a remote on/off switch, but did throw a passing glance at the switched 110V outlet on the back of the webcam.

Speaking of which, the webcam is working brilliantly, but the temperature in its little housing is up to 34C. Does anyone know why this might be? There's also only one perspex dome in place - I guess that's fine but not quite as energy efficient as with two.

Abu has now been switched off as it's clearly not going to get cold enough. Al Fowler is walking around looking depressed, waiting for Al Harper to turn up with the new cold head.

I've recorded the sodar song on my Mac in preparation for creating a .wav audio file on our home page. This will allow folk around the world to experience the delight and pleasure of an optimised echo-sensing tone sequence. Ambitious web surfers may also like to play it through their hifi at terrifying volume, thus truly recreating the sodar experience and provoking involuntary flight instabilities in passing birds.

Peter Gillingham has spent the day machining up new pieces for the tip-tilt secondary. He's resurrected the incorrectly made Invar backing plate that everyone else said would be too much work to fix. Peter has also cast his expert eye over the G-tower: "mostly good, but the stiffness is compromised by the poor pin-joints at the end of the struts". He's even come up with what I consider to be the most plausible theory so far on why vibration is mysteriously coupled from the MAPO building to the SPIREX telescope - as a sheer mode through the long canvas strips that seal the floor.

Meanwhile there's been an outbreak of graffiti on the wall of the solar-powered dunny, as various people attempt to prove or disprove the existence of god. The alt.toilet.religion discussion group has yet to go on-line.

The 18th to 26th no-fly period appears to be a reality, and confronts me with the difficult choice of leaving the Pole early before everything's finished, or getting home too late to stop the School of Physics collapsing in a big heap. Unless a major problem occurs in the next couple of days, I think I'll leave here on Saturday (there are no pax flights on Sunday) in the hope of catching the last flight to ChCh on Monday the 18th.

We had another tour of the AASTO by folk from the AGO (Automated Geophysical Observatory) project. They were very impressed with our instruments which are clearly lots more fun than geophysical ones. They were completely blown away by Melinda's 24 hour webcam movie which demonstrates, unequivocally, that we are at the South Pole. They said I should make sure Melinda makes another one - maybe several so we can pick the best one - very soon. (Actually I'm making that last bit up.)

John

Wednesday 13th January

From Michael Burton.....

Greetings from the Pole!

Coming towards the end of my first full day here now. After 4 days in Christchurch things moved fairly quickly and I was through McMurdo with just an overnight and down to Pole. Temperature a mild -30 right now, and sunny conditions, though I have to say I haven't quite acclimatized as yet! The altitude always hits you when you first arrive, but by tomorrow I hope I will have adjusted and feel like some real work.

The delays in ChCh meant I missed the Scott's Hut race in McMurdo by 1 day, and also the most fabulous ice-halo display. The locals believe it may even be a world record for the most number of different halo forms (24) ever seen in a single display - have a look at www.spole.com (which will be up about half the day for you) to see some of the spectacular shots of what ice particles high in the atmosphere can produce.

Pole is as crowded as ever, with many new experiments, and some of the old, all sharing the space, together with a large complement of construction crew who are starting work on the New Pole Station (a 5 year project). I came down with 2 of my students, and John Storey and Peter Gillingham (AAO) are also here. We seem to have got one of the expts going (a SODAR, or acoustic radar) but there are some major problems with the infrared camera at the moment.

I must admit the sense of adventure coming here is not quite what it was in the past, this being my third trip now, but it still is an incredible place and we are a long way from home. 2 sets of adventurers have passed though, a French expedition who were on the final leg of the '3 Poles' (Everest, the North Pole and the South Pole) having skied here from Berkner Island, and a Dutch group who paraglided here (attach sails to your sleds). The latter group are actually trying to cross the continent and end up in McMurdo, but are probably too late already, and are looking like they need to be rescued! And we are expecting a Kiwi expedition
in a few days, lead by Peter Hillary, Edmund Hillary's son (who was, of course, here in 57, as well as in 97)

Michael

Thursday 14th January - Snow Storm

From John Storey.....

Last night lots of Hercules arrived when I was trying to get to sleep, and then I started dreaming about Hercules only to be woken up by another arriving. But the one I was dreaming about was even louder so it put me back to sleep again (I think).

When I awoke the station was in the midst of a snow storm, with a 36km/hr wind blowing at right angles to the runway and wind-blown snow going everywhere. Visibility was down to about 50 metres. They even closed the big doors at the front of the dome - something I've never seen before and in fact I didn't even know the doors existed. Bob Lowenstein was also surprised by the doors, as he hurtled down the big slope to the dome entrance on his skis...

Under normal summer conditions here, when the wind is low and the temperature above -30C, I'm quite comfortable walking around in my Rockports and with my hands retracted into the sleeves of my parka as a substitute for gloves. However today was a stark reminder of how quickly the weather can get very nasty, when nothing short of the full ECW gear will keep the elements out.

It was very pleasing to see *no* snow accumulation on the sodar antenna. As hoped, the cover shakes like a drum-head in the wind, and keeps itself completely free of snow. On the other hand the sodar doesn't work at all when it's windy. Daniel says it's because the noise of the flags flapping etc drowns out the echo.

Daniel and I made an insulated collar for the antenna so that its little bottom can be kept as warm as possible by the AASTO room heat.

Peter has finished machining up parts for the tip-tilt secondary and has reassembled it. He's also measured the weight of the mirror and the spring constant of our phosphor-bronze diaphragm spring, calculated the maximum acceleration of the mirror and adjusted the tension accordingly (ie, to about one tenth of what it was before). He has also beautifully documented all the details, setting new standards for the project.

Abu is sitting forlornly while we await the arrival of Al Harper and the new cold head. At last count they still hadn't left Christchurch.

I tried to get the Toshiba to work but without success. The power light doesn't come on and it makes no attempt to read the floppy. Technically speaking, it's stuffed.

I'm about to put the SBIG camera and X-Y stage and Vectra computer business together, and see if it all works. Al Fowler has zero confidence that I'll be able to figure it out - slightly more than I have. Actually it looks pretty straightforward, but I can't help wondering:

1. Why the "Z" motor on the X-Y-Z stage is loose,
2. What the spare translation stage is for.

Today the AASTO had a visit from a reporter from the Washington Post. He is writing a major article about Antarctic physics, so we gave him the full tour. He especially liked the webcam movie, and said he was very keen to see the new one that Melinda is making.

Thomas has contacted PI in Germany on our behalf and arranged for them to specially make a replacement PZT. This can be flown out to Christchurch in a couple of days, which is fantastically good news.

The latest addition to the upstairs lounge is - to my complete astonishment - an automatic ice-maker. That's something that's clearly going to be really useful here. I'm going to survey other US stations around the world to see if the lounge in Saudi Arabia has an automatic sand maker. Such a trend in completely superfluous appliances could lead to a fog machine for the London embassy and an aphrodisiac dispensing machine for the White House.

Matt has been initiated into the delicate art of dallas dangling, and has rewired the sensors to the "big" supervisor computer. The new wiring complies strictly with the definitive dallas dogma of the dallas-danglin' big daddy himself (mcba): ie a straight daisy chain with no branches, twisted shielded-pair cabling and 0.1 mu capacitors at every point where voltages might otherwise be tempted to get out of hand. It's also routed mostly away from other digital cables - as long as you don't count ethernet as digital. With luck it will work more reliably than last year's wiring, which was basically a carefully uncontrolled experiment to see
just how tolerant the dallas sensors really are. Here's the detailed dallas designation dope:

1400000008D34910 Flag pole (Australian), 1 metre above AASTO
3B00000008F1A510 AASTO ceiling next to air intake baffle
E800000008D42B10 Sodar baseplate

Since last summer the station has acquired a brand new Caterpillar tractor for dragging the snow grader and other things around. It's one of the modern curvy ones with rubber tracks and has been named, appropriately enough, "The Drag Queen". Caterpillar certainly seem to be the heavy machine of choice around here. As the bumper sticker says: "If it ain't a Cat, it's a dog."

John

Friday 15th January - Sodar Problem

From John Storey.....

Today we fiddled around with the sodar, and discovered a major problem. It appears that when the flags (the big US and Australian ones) are flying the range is dramatically reduced. We tried tying the flags up, and the sodar once again worked properly. We'll do a couple more flags on - flags off trials, but it does look as if the flags will have to go. For some reason a square metre of fabric flapping around 2 metres from the sodar appears to create a larger acoustic reflection than a millikelvin turbulent air cell at 600 metres.

Removing the two flags will devastate our webcam audience, who average around 500 per day. Typical emails we get are: "Please send me information on penguins", "Your thermometer is too hard to read", "Why don't I ever see anyone working outside". We are bracing ourselves for some strident email criticism, but science must come first. I'm working on an explanation that involves Richard Butler, US air raids on Iraq and the need for all Australian/US endeavours to become less conspicuous. Mind you, we could see the first Iraqi ski-team to cross Antarctica towing a belt-fed mortar or similar AASTO-destroying device. It would make a change from bare-foot skiffle-boarding Antarctic-crossing adventurers.

It turns out that the Toshiba was not actually dead but merely in a coma. The battery was too flat to allow it to work, but by leaving it plugged in to the charger overnight it was able to recover. Unfortunately the DCU is not operating at present, leaving the Toshiba with little to talk to.

I'd put myself down to give a Sunday night science talk, but since I'm leaving tomorrow the task will fall to mgb. I trust he will resist the temptation to do Elvis impersonations - the South Pole does strange things to people.

Tonight's CARA meeting featured *real data* from the Sodar that Daniel passed around to critical acclaim. To my enormous relief no-one seems to be irritated by the noise. In fact, the winter-over crew feel it will be very useful to help them find their way out to the dark sector at night.

Today we had a major tidy up and vacuum clean of the AASTO.

We've packed up everything instrument-specific in the AASTO and will "retro" it to UNSW. We'll leave the big general purpose PC down here until Daniel leaves - my inclination is to then return it to UNSW as it simply takes up too much space in the AASTO.

Peter G. has left on this evening's flight, having done a wonderful job of reconstructing the tip-tilt mirror stage. Al Harper has arrived, and is acclimatising. I am disappointed to learn that helicopters are no longer being used to ferry passengers to the McMurdo airfield. While I am normally a strong supporter of the use of seatbelts, fitting them to the van to make it safe enough to render the helicopter unneccesary seems to me a cheap-skate, short-sighted solution and completely inappropriate.

Webcam devotees will have noticed a gold ribbon tied just below the thermometer, and no doubt have been wondering what it's doing there. There may even be an alt.aasto.webcam.gold_ribbon discussion group for all I know. Well, today I found out how it got there. On New year's Day, two South Pole folk got married at the Ceremonial Pole and tied the ribbon from their wedding cake onto the webcam for the world to see. Isn't that sweet?

I'll hand carry the broken PZTs back to Sydney so they can be rebuilt.

As I suspected, the PC in the AASTO had been set up especially with a trick version of Windows 95 as part of a fiendish psychological experiment (which I clearly failed). My suspicions were confirmed when Daniel walked in and was immediately able to log into other computers, print files and actually do useful stuff. I don't know what the psychologists will do with the data they have collected on me, but I fear it may not be to my advantage. In future, computers will probably choose the people they wish to work with (instead of vice versa), and I may end up simply being left on the shelf.

The shrinks finally caught up with us at dinner, where Joe was doing his "two corks" trick and Peter G. was challenging all comers to his "row of toothpicks" game. After half an hour or so the two shrinks were so perplexed they proceeded to certify each other.

CBS have completed their filming, and headed off to other parts of Antarctica. I will forward to you the message we received about screening times.

John

Saturday 16th January

From Michael Burton.....

About the hardest thing about writing a diary entry is remembering the day of the week - there is no reference point down here with which to hang your outlook of life upon!

We've had some mixed weather, going from miserable to gorgeous. A couple of days ago it got as bad as it can get at Pole. Bad weather always means its warm (Around -20C) but it results from 'moist' air entering the Antarctic continent from the coast, bringing winds from the wrong direction, fog, and a stiff breeze. Its the latter which makes moving around somewhat difficult - and indeed I took the shuttle bus out to the Dark Sector a couple of times instead of walking.

The SODAR (our acoustic radar) didn't like the comditions either and couldn't tell us anything about the boundary layer turbulence, presumably because there was so much of it that it scattered the signal every which way but back to the detector. I've also found that the local computers are *very* much slower than my pet machine back at UNSW. Its taking about 10 times as long to do the same data reductions with it as it takes me at home, making me wonder whether, even with 24 hours a day to work in, I'll manage to actually reduce the data I have with me from last year!

We had an interesting Science Talk the other night, on the Greenhouse Effect. The Pole is ground zero for establishing the baseline for global change, and is showing clear and accelerating upward trends in CO2 content of the atmosphere. Its quite clear there is going to be a temperature rise over the next few hundred years for us, its just a matter of how much it will be and whether we can slow it down.

I had some trouble sleeping last night, so I got up at 4am, which is when I can catch the fast satellite, for transferring data back and forth from Pole to UNSW, and then went to be and fortunately fell asleep immediately.

Today the bad weather finally cleared, bringing in a beautiful blue sky with little wind. Its only -25 still and it actually feels quite hot walking out across the runway to the Dark Sector.

Ice haloes are caused by ice, not water, and it is on the high plateau where the best displays are seen. In fact its all got to do with the refraction of light off hexagonal plates and pillars of ice, and its quite amazing the variety of patterns that two simple shapes can make.

Several of the computers at the Pole are named after well known horses, for no particular reason. The first winterover to use this particular computer was an Aussie and he just liked the name!

Michael

Saturday 16th January - The End

From John Storey.....

The subject title alludes both to this being my final email report for the season and is also an apt description of McMurdo. Even after just a week at South Pole, McMurdo is a grim return to reality. I hope to be here no more than 36 hours. Within 15 minutes of getting off the bus, one is confronted by:

1. Dirt, which is not as nice, and not nearly as white, as snow.
2. Keys, which are an extraordinarily anti-social invention.
3. An absence of keys, to useful things like the computer room.
4. A dining room with no food in it (seriously!) until midnight.
5. Computers that require a user name and password, which one does not
have. (Although hacking around the security is very satisfying.)

Nevertheless, today was a good day at the Pole. By noon the sky was completely cloudless and there was zero wind. Although it was -28C, it was very pleasant. By 1 am last night Al Fowler had installed the new cryo-head in Abu, and was pumping it down. He seemed happy.

The sodar continues to sing its merry song, and Daniel is exploring ways of improving the signal to noise. These include better grounding systems and worrying about flags and things. Matt has packed up all the parts associated with the old experiments (NISM, MISM etc.) ready for sending them to Sydney.

I gave a guided tour of the AASTO to Charlie Kaminski, who will be the winter-over looking after both the AASTO and the Abu/SPIREX experiment. I think this was the only useful thing I did today.

The webcam was at +52C today, a stunning demonstration of the Greenhouse Effect.* Andre has suggested a solution involving drilling holes and sticking corks in them. Could I propose a less invasive solution: Matt or Daniel, please go to the kitchen and chat up the cooks. Relieve them of approx one square foot of aluminum foil. Cut a hole in the middle for the camera to peer through, then wrap it around the webcam bubble. Cut another little hole so you can read what the temperature is!

(*Of course greenhouses don't work because of the greenhouse effect. Rather, they supress convection. Likewise the webcam housing.)

By the way, have you ever wondered what happens if you stick a CD in a microwave oven? The result is very pretty and probably has a lot to do with standing waves and mode structure. A fine example of this modern artform is hanging up in the control room for SPIREX. One can't help speculating about the result of the *opposite* experiment - namely what will happen if I shove a frozen chook into the CD drive? This experiment was in fact nearly conducted on a McMurdo computer an hour or so ago, until I found a way around the login security.

I will close down my "magnolia@spole.gov" account within a week or so, so please send all future mail to UNSW. Thanks to everyone who's helped this season, thanks to the patient readers who have waded through these diaries to the bitter end, and good luck Michael, Matt and Daniel who have to bring the experiments to a satisfactory conclusion.

John

Monday 18th January

From Michael Burton.....

Well now John has departed this fair and beloved icescape (and become marooned in Mactown) it falls to me to attempt to carry on the tradition of the daily South Pole diary. So what happended today? Got up at lunch time, wandered out to AASTO, wandered back again, did a little exercise, had a shower, took a few piccies. Yes, all in all a busy day now that John has left.

But getting serious for a minute, a few things did happen. Al Fowler decided that Abu wasn't pumping down properly, did a few checks with the leak detector, and discovered a leak near where the pump connected in. So pumping needed to be restarted. So far it looks as though its going better, but there is a couple of days to wait before we know whether our dewar really can hold a vacuum.

Matt has been busy resoldering wires for the SPIREX secondary mirror and sorting out and packing all the gear we're sending back to UNSW. Daniel continues to monitor the SODAR in all types of conditions, in particular trying to determine whether its the US flag or the Aussie one which is contributing to the turbulence measured. He's also started correlating the data with that of the Met balloons, which are launched twice daily. I expect him to be writing a paper soon on the inadequacies of meteorlogical data gathering methods! Actually the disagreement in our data sets on wind speeds and directions isn't that bad, but there is certainly NOT a one-to-one correlation between the two! The wind has, however, been pretty miniscule of late, when the swaying of the balloon payload dominates its readings. We're waiting for some strong winds to develop so we can make a better comparison.

Talking of weather, we're experiencing a heatwave. Temp around -25C. Its hard to cope. Clothing is being discarded, people wander around in T shirts and shorts, and curse the heat. We had a glorious 12 hours when the wind was absent and the Sun shining. Then the clouds came in for a few hours but now they've cleared again. Having been trained in the delicate art of taking movies with the webcam by Melinda (a very tricky unix command needs to be typed in on our local computer, pharlap) I've started the filming for the epic movie, `A Week in the Life of an AASTO', a picture every 4 mins. But there has already been a 8 hour gap when I decided to stop filming for some poor weather, only to miss the reappearance of the Sun. I'll probably get the tecqhnique right just about by the time I'm ready to leave!

If people have been wondering what I've been up to at Pole, while all this hectic activity goes on around me, I've been stuck in front of a keyboard trying to get to grips with reducing the SPIREX/Abu data from last year. One thing became immediatley apparant - how good our computer system is back at UNSW (our friendly decstation `roen'), compared to the Sun workstations I have available here! 1024**2 arrays really do generate a lot of data and when you are trying to process 100 images at once you need a computer with some real grunt, not to mention ample disk space. I've ended up shuffling files between 3 computers, parallel processing as I go, in an attempt to make progress. It must be about 10 times slower working than on roen, but since I have about 20 times as much time available to actually work as I do back in Sydney, I am making progress, just. I have, for instance finally worked out the sensitivities we reached through all the different filters we used last year. Any Abuists reading this diatribe - I will post the results shortly!

I also gave the weekly Sunday Science lecture tonight, a task neatly transferred to me by John when he decided to do a runner and hit Mactown for the weekend. Still, the galley seemed pretty packed (I guess there isn't a great deal else to do?) as I wizzed through a slide show on why study the Galaxy and used John's viewgraphs to talk about why come to Antarctica and where we really want to go.

So that will have to be it from me for tonight - its time to crunch some more data!

Michael

Tuesday 19th January

From Michael Burton.....

A bright sunny day at Pole, with the temperature creeping down towards -30C and a notable absence of any wind. A pleasant day for a stroll to the Dark Sector and back. Life continues apace with CARA; there were 30 people at our biweekly meeting last night working on 5 major projects and its getting a little tight for space in the MAPO building. The arrival of a large crate meant that you literally had to climb over the furniture to access and work on delicate instruments like dewars, three of which seem to be littering parts of the floor at the moment.

Abu is still on the vacuum and pumping hard, and Al Fowler looks worried, but its hard to judge whether this is just his usual worry or whether its more serious (ie we have a vacuum leak somewhere in the system). He plans to start cooling tomorrow and the instrument will be placed on the telescope by Friday, whether or not its really ready, as people cant stay here for ever. We're also waiting for a replacement piezo to arrive for our secondary mirror, which allows it to compensate for any untoward motions of the telescope. This has to be here by Thursday or we simply have to work without it. So its fingers crossed for a few days.......

Daniel still experiments with the Sodar, but its possible we aren't getting any sensible data at all with it at the moment. A Herc parked outside the Dome, a kilometre away, creates total garbage in the system, and I expect passing Caterpillar Tractors dont help. The South Pole is just too noisy a place! However at least these distractions will be absent in winter, which is when we want to gather our data. I guess microthermal flucuations in the atmosphere 300m above our heads dont really rate when competing with passing heavy machinery!

Matt has decided to attack the Orbcomm transmitter, and bits of wire and solder were littering the AASTO today. Even the communications expert from COMMS was called in, and commented maybe we had a dodgy transmitter (thanks!). So John, John and Matt have been baffled by this wonder piece of technology. Andre, where are you when we need you?!

I thought my movie making abilities were secure given the good weather, but a recent check of the webcam shows that it hung up about 12 hours ago, and so I've missed once more the 24 hour shadow-circle we're trying to capture on film (thus updating, ever so slightly, the original method Amundsen used to find the Pole in the first place!). Following Matt's pioneering efforts at Antarctic ice-running last week, I thought it time to come of the treadmill in the gym and run the skiway too. The skiway is about 100m wide and 5km along, just about big enough for an errant Herc pilot to catch if dozing off after a hard night at MacTown, and provides a hard surface to run on. The snow is jus too crunchy off it, and a real effort to trudge through, though its fine on skis. However the biggest problem with running is what to wear. Its just too hot here for the clothes your provided with, even though I removed a couple of layers! After 30 min I was nicely toasting and sweating profusely, which over the second half of the run then started to turn to snow and ice on the outside and giving me the appearnace of the abominable snowman. Next time I think I'll stick to my shorts and T-shirt!

That's all folks!

Michael

Wednesday 20th January

From Michael Burton.....

There's a brisk chill to the air, not that the temperatures dropped much (its still holding above -30), but because the winds picked up. Only a few m/s mind you, but enough to make it noticeable if still going around in jeans and training shoes! I think I'll have to remember to put a bit more of my Antarctic clothing on tomorrow. The weather continues to be beautifully sunny, with barely a cloud in sight, quite unlike McMurdo where John is still believed to be holed up, waiting for a Herc to appear to whisk him back to NZ.

Regular viewers of the webcam may have noticed some strange happenings around it around midnight last night as three strange individuals were seen showing that it is really high summer in Antarctica, performing some kind of ice-bonding ritual. Doubtless Melinda has turned the images into a MPEG movie by now, so enlightenment will be forthcoming! The mega-movie `A week in the life of an AASTO' continues filming, frames coming in every
4 minutes - so there will be some rivetting viewing ahead.

Matt & Daniel decided to place the anemometer back on the G-Tower, and to start cabling it up - so a trench has appeared between the AASTO and the G-Tower. Even more surprising when I entered inside today was to find the AASTO servicing crew, lead by Ron Rainbow, there! We weren't expecting them at Pole till Feb, and nor did they it seems, but somehow they had arrived on one of the flights yesterday and were busily servicing our unit. They had a "freon leak meter" which busily chirped away and announced that freon is indeed leaking along one of the inlets. Even further, they found a cracked socket joint (with a 0.5mm crack in it) just were the meter beeped, and even replaced it. So perhaps the problem is solved??!

At the same time the propane tanks arrived for the year and were deposited outside by caterpillar tractor. I thought the whole event was being beautifully captured by the webcam movie, until I realised it was that time of the day when the Sun shines directly into the camera, obliterating everything. So all webcam viewers will see is the sudden appearance of a set of propane tanks, beside the new location of the Aussie and US flags (we'd also decided that we really ought to move the flags off the roof just in case their flapping really does interfere with the turbulence measurements we're trying to make with the SODAR.)

We've been a little concerned about the temperature inside the webcam enclosure, which has been reaching over 50C when the sun is shining directly on the plexi-glass! So today we took the radical step of taping some aluminium foil around the whole structure in order to reflect sunlight away. With 5 min the temperature (or the thermometer inside anyway) had dropped by 25C, so we must have done something!

Abu, unfortunately, is still not cooling down and Al is out looking for vacuum leaks again. This is getting quite serious now as time is running out for having the instrument ready. Fred is convinced that the problem will be solvable though, and its good to have an optimist in times like this! The delay also means that the replacement PZT for the secondary mirror might actually get here in time to be installed before the instrument goes on the telescope. After couriering the part from Germany to Christchurch it has been hand-carried to McMurdo we believe, and are told it will come in on a flight tomorrow.........

Tonight we had a lecture on the construction plans for the new Pole Station, due to be completed in only 2 years from now if I read the viewgraphs correctly. We will be placed in nice, plush building elevated above the ice and may even have windows! Summer camp was proposed to be disestablished - but on the other hand the new station on has accommodation for 110 people, and since we have over 200 present now its hard to see the station population really declining, even if you do get rid of 80 constructors!

Michael

Friday 22nd January

From Michael Burton.....

What a difference a day makes in the weather. From a series of beautiful sunny days we have now changed to about the worst that the weather brings at Pole. As usual it is due the incursion of coastal weather patterns, bringing 'warm' moist air inland. In fact its only -23C now, but with a wind speed of upto 30 knots, the wind chill brings it below -50C! Visibility is minimal and you have to keep sight of the flags as you struggle the km between the Dome and the Dark Sector on the way to and from work. Several flights were scheduled today, 2 even made it off the ice at McMurdo, but got to Pole, flew around overhead for an hour hoping there might be a break in the clouds for a minute to land, and then just had to turn around and make the 3 hour trek back to McMurdo. In the second flight were a bunch of ASA admin-types who were here to conduct a meeting about redeployment back to civilisation at the end of the season. The meetings now cancelled, and, I guess, so is redeployment!

However bad weather doesn't stop us Polies making progress on our experiments! The AGO crew (Ron Rainbow and Joe) were hard at it in our AASTO giving it its annual service. They found what they think is the source of the dreaded freon leak, a cracked swage-lock fitting for the inlet pipe, and replaced it. They hooked up the external propane tanks, fired them up, and it is now nice and toasty inside the AASTO - perhaps too toasty indeed! A glitch with the recording of the health and safety data has some erroneous figures coming out of the Argos satellite into the www site at Augsburg where you can see how all the AGO's are doing across the plateau (space.Augsburg.edu) but our local expert on wiring, Mark Tomah, reckons he can fix it once the AGO crew are gone!

The trench Matt & Daniel dug yesterday has, unfortunately, filled in before they got around to putting the cable in, so they will have to re-dig tomorrow. The webcam, now its been sheathed in aluminium foil to stop it getting too hot, seems to have settled down to the thermostatted temperature of +15C now the Sun is invisible! Even some frost started appearing inside the plexi-dome, though equally quickly had disappeared when I looked again a few hours later. The great webcam movie continues to grow apace, though I felt the need to remove the sunglasses from the eyepiece given the conditions, though anyone looking in over the web will barely see anything right now! One benefit of the weather is that the size of the image files produced is reduced quite considerably, as there is now barely any dynamic range in the pictures!

Matt, Al H and myself talked some science tonight, going over a couple of the many (!) papers we have / are going to write about the various data sets we are assembling. Andre we might now want some more input on the IRPS paper, by the way! Then I discovered I had made a subtle error in the various sensitivity calculations I'd been doing, so now have to restart them again! I dont think the difference will be huge, but its always annoying when this happens!

The bad news is with Abu. The PZT still isn't here, coming within a (vertical) kilometre of the Pole before heading back to McMurdo. And Abu really isn't cooling down the way its expected, though is slowly grinding down to cryogenic temperatures. Its really too early to say whether we will actually have a useable instrument for the season, I'm afraid, though we all have our fingers crossed. Some of the other telescopes make progress. AST/RO (the sub-mm one) has opened its covers to have a peak at the clouds. SPARO, a sub-mm polarimeter, has been placed at the focus of the Viper telescope, after some drastic redesign of the telescope optics when it was found that the secondary mirror was vignetting half the field of view of the instrument (woops!). However Liquid Helium supplies are low at the moment, and unless some more arrives in the next 3 days both AST/RO and SPARO are going to warm up!

The station so far is 60 flights short of getting enough fuel to last the winter. The program is way behind schedule due to the delay in opening, mainly due to bad weather. Tomorrow 7 flights are scheduled in, mostly fuel tankers, and will make it #200 for the season. But there are of order 100 more flights needed before station close in just over a month. The French adventurers are still with us after 12 days! Apparantly a Herc flight with fuel finally reached Patriot Hills, so that a Twin Otter will now be able to slowly make its way from there to the Pole if the weather clears up. And the Kiwi "Ice-trek" team (with Peter Hillary, son of the famous Sir Edmund) still remains about a week away from Pole. They were about a week away when I left Christchurch, so they are making *very* slow progress! As for the Dutch paragliders who left a week ago, no word. We're presuming they'll be calling for "help" soon and wait around to be picked up by the Adventure Network people, once they find enough fuel to pick up the French.......

So its all go at the moment on the Antarctic Plateau!

Michael

Saturday 23rd January

From Michael Burton.....

Well after a couple of days of brutal weather, the clouds have gone, the wind has eased and the Sun has come out again, and even the Hercs have started arriving again! Then there's been the the steady chug of caterpillar tractors running up and down the ice all day dragging giant snowploughs behind them as they clear up the great snowdrifts that have accumulated behind all buildings, and re-grade the skiway and other walkways about town. Its gives those of us who are temporary residents a little feeling for what it's like in winter when Mother Nature is allowed to reign unchecked and the snow if left to lie where it falls!

The good weather could be seen as a sharp line of blue sky way to the north this morning (that grid N) moving slowly towards us with the wind. About noon the bisecting line between blue sky and cloud was directly over the station, with at one point the AASTO in brilliant sunshine and the Dome under cloud. An interesting observation of a change in the weather system moving unhindered across the continent.

The first Herc in brought us a replacement PZT for the secondary mirror of the SPIREX telescope, and its now installed, though not without a few concerns as it doesn't seem to have been manufactured exactly the same way as the others we have. I guess we'll know fairly soon whether its going to work.

Al Fowler is happy, which is a good sign for all! Abu is now definitely on its cooling curve, and after 48 hours is getting close
to the cryogenic temperatures we need it at if it is going to function. Another 10 hours on the pump and it should be there. The little extra load we placed on the system this year has been enough to take the pump right to the hairy-edge of what it can cool down, something Al was unaware of until he tried. So it looks like we may have a working telescope and instrument for the season!

The AASTO, on the other hand, is definitely an unhappy camper right now. The servicing crew have been and gone, and left it without its power system on!! There has been some considerable trouble with the cooling system, with the freon which is supposed to circulate and remove the excess heat, leaking, and the radiator itself being blocked. Our little portacabin on the ice has been getting up to about +40C inside, while the windchill outside was below -50C! Definitely very toasty inside, especially in our polar clobber, and not good for the freon which goes gaseous at these temperatures, thus exasperating the leaking! In an attempt to fix the blockage by the trusty method of wacking the radiator and pipe with a wooden stick it appears that another valve was cracked causing freon to leak once more! So the service crew have decided that drastic action is needed, which is to take the radiator off completely and bring the system inside for a thorough going over. Only, now the Hercs are flying again, they have headed north on another job, and wont be back till sometime in Feb! Charlie, our trusty winter-overer has decided to look into the problem himself and is now searching for leaks in the radiator by pumping down on it, and running a helium leak checker over it, just like you do for any cryogenic vacuum system! This might be overkill for our system, but at least we should know everywhere it has micro-pores in it afterwards!

Since the Sun has come out again I decided it might be as well to place the sunglasses back on the webcam, but ran into a minor technical hitch. The hi-tech blocking-filter-removal-module (BFRM) that Andre had designed (a piece of string with a bullbog clip on one end which you pull through a hole in the back of the camera mounting) worked great at raising the sunglasses, but not so well for putting them back on again as they run into the camera body! Well I discovered this at about 6am today, which is about my bedtime round here, and I was too tired to do anything about it. But fortunately Matt, who
wakes up about that time, spotted the problem and went to it with a screwdriver, removed the plexi-covering around the camera, fixed the sunglasses, and put it all together again! A remarkable piece of polar engineering at work!

The Orbcomm transmitter spoke! Matt's lashed together ground plane aerial actually did pick up a signal with Matt running around with it held on a stick as high as possible when the satellite was at its near point to us. A test email message did get out directly from the AASTO without going via the internet! Not that we've quite got the system to a useful data transmission rate, but its a start in making the AASTO independent of the need to have a local ethernet available with which to communicate with it.

Daniel continues to investigate all kinds of weather conditions on the SODAR and write up the definitive works on its use in Polar conditions, as well as knock holes in the reliability of any wind measurements from meteorological balloons! The SODAR had developed a nasty squawk to one of its notes, but, as mysteriously as it occurred, it seems to have cleared up.

I've been continuing to play around with the data reduction software, getting around to looking at some of the code that hopefully will be used for our data reduction pipeline. This is a little different to the code I've been using, and I've been wanting to compare methodologies and results. Somewhat to my surprise inside an elegant package I've found a number of simple errors which rather mess things up as regards to getting results! But I guess that's life when you're
dealing with software!

That's all for now!

Michael B

Monday 25th January

From Michael Burton.....

This may be my last journal report from the South Pole! I'm due to fly out to McM tomorrow (well actually today, but since I'm on a night schedule that means tomorrow for me!). The weather's now beautiful and it looks like things are working, so its fingers crossed for another great season!

Devotees of the webcam will have seen the great weather we're now having. Barely -28C and next to no wind, with great blue skies - its wonderful! Two Twin Otter's arrived last night, from Adventure Network International, to pick up our French adventurers (at last!) and also the Dutch paragliders, who'd radioed in to say they had only 1 days food supply left and please help! What that really means is that there is likely to be a food cache about 100 km out from Pole in the McMurdo direction if anyone feels like making the journey here one day.....

The Kiwi's, on the other hand, still seem to be struggling on. I heard today that its actually an official government appointed program under their Antarctic program, and thus that the Yanks will pull them out on Hercs if/when they get here. Sounds like an interesting way to be spending their meagre budget, but I guess when the PM can make calls to them on the Iridium phone and get it broadcast nationally, what does it matter about the cost!

NSF are apparantly going to have to apply some hard words to ANI for leaving their clients at Pole so long, after they had arrived on time!

The TEG is running again on the AASTO! After the AGO boys had left Charlie, our cunning winterover, decided to just put the radiator back on himself, fix up the connectors, and switch on power again. So far no freon leaks and everything seems to be working.....

SPIREX, the 60cm telescope, is back together, and now just awaiting Abu, its million pixel infrared camera, which is scheduled for tomorrow when they can get the crane operator to drive the massive mobile crane over. Measurements of the background flux from the instrument in the lab were high, but if I have my calcs right by the time it drops to -60C in the middle of winter there wont be much emission to worry about from the instrument, just that from the sky and space beyond. Lets just hope that Planck got his radiation formula correct!

Then comes the task of making sure everything is lined up, we can find stars and track on them. Its another few weeks work, but there is a hard working team from CARA here for the job.

I've been sorting out lots of things to do with how to process the data this year. We're trying to be really clever and automate most of the process using some software gurus in Rochester in the US. However, since it is software, this process probably wont prove to be as easy as it sounds on paper!

We are being visited by DV's (or Distinguished Visitors). Arriving tonight, as the only passenger in a Herc, was Karl Erb, the recently appointed Director of Polar Programs in the NSF. Tomorrow we have several other heavies as well. So all the PI's have been madly typing into their laptops summary and fact sheets to impress the DV's by as they make their whistle stop tour of the facilities. Those arriving tomorrow only have 5 hours at Pole, and are due to see everything. Given that it takes at least a day to acclimatise its going to be a tough day in the office! I've been given 10 minutes to make my mark with them! Actually what we really want to do is open their minds to our next project, SPIRIT, the 2-m telescope we want to start building at Pole in a couple years, and for which the chase for funding is now beginning in earnest! So we all have to be on our best behaviour tomorrow and put on our best pair of jeans for the occassion.

So weather permitting, this will be my last message from Pole, though there may be a few commenting on the delightful food at McMurdo. Daniel will have to take over the reins for the rest of the week!

Michael

Tuesday 26th January

From Daniel Marlay.....

Mike Burton has impressed upon me that it is my responsibility to continue the epic South Pole Diary now that I am the sole UNSW representative down here.

Mike got away early this morning (10:00am) with the DVs and all the other passengers who had been delayed with them. That was the first time that I've ever seen a Herc with its propellors stationary down here. On other incidental news, Peter Hillary has finally arrived here at the pole. He and his team spent the latter half of the afternoon walking from the point at which they were first spotted, across to the pole. They have just delivered a mildly interesting (pole expeditions are getting a bit ho-hum these days) talk about there trek over here. They don't seem to disappointed at being possibly the slowest team ever to reach the South Pole.

On the AASTO front, I spent the day finishing off the various spreadsheets and documentation that I've been working on. I'm finding out about getting the computer back and whether we will require an excess baggage allowance. I'll know on that front fairly soon.

I have been checking the readings coming back from the wind vane, and have ascertained that the readings from our windvane are within a few degrees and less than a meter a second of the station wind vane. Looks like that worked well. Is there some way of checking the data that is being monitored by the housekeeping software? I tried running DCUMON on the laptop, but it don't seem to work. Also Ron Rainbow did enquire when he was here as to whether that laptop was ours (the old Toshiba). I informed him that it was (given that we carted it down here this year). Did I inform correctly?

Bob Lowenstein (SP?) has started to work on a script that will automatically check the Dallas Semiconductor temperature sensors every hour or so to see whether the temperature is dropping or not. This script should hopefully provide the winterovers with some warning as to whether the TEG is working or not. They are concerned that a heater with a thermostat will operate above the 0 degrees C point. If it does this and the burners go out, then the propane won't automatically shut off, and you have the makings of a nice black mark surrounded by some pretty yellow poles. The Orbcomm has not been successful yet and so I have packed it away, ready for the trip home.

Well I think that just about covers today's business.

Daniel Marlay
UNSW / CARA / JACARA / AASTO person

Wednesday 27th January

From Daniel Marlay.....

Well today saw the final cleaning up of the AASTO in preparation for my departure tomorrow. I've tidied the place up (vacuumed it all as well) in the hope that it may be left in a decent condition when Ron Rainbow leaves. I have completed the documentation of he SODAR installation and testing, and left copies of this in the AASTO. Charlie Kaminski has been given a copy of my instructions for using the SODAR, along with a bit of a demonstration by me. I've ascertained that the computer doesn't put me over the 70 pound luggage limit, and so there should be no problems bringing that back (although the shift of gear into my hand carry has made it a bit of a hand-only-just-carry).

The AASTO temperature was a toasty 33 degrees when I opened it up today. I had a bit of a sniff around with the freon meter, and it registered freon around the big radiator valves and near the tank. After opening the windows to get the air circulating a bit, the freon meter failed to register any freon around the pipes and tank. It may be that a small amount, sufficient to be detected by the meter, escapes and stays around the tubes when the windows are closed, But disperses quickly once even a small through flow of air is established. I've closed the AASTO up for today, but I will check it again tomorrow before I leave.
Michael Burtons wallet was found in the computer room, and will be flying the secure skies via Dan Air back to him in McMurdo. It is just a little worrying that Mike, who left a few days before me, will still be in McMurdo when I arrive there. Hopefully I won't end up having to stay too long at Mactown.

My flight out of here leaves in about an hour, so time to give the final wrap up on the AASTO. I went out and gave it a brief checkover this morning. Charlie opened the valves on the Radiator a bit yesterday, and so the place is cooler now, about 25 degrees Celsius. I did another quick check around with the freon sniffer to see whether the leak that I detected when I first entered the AASTO yesterday had developed again today. The answer was that it hadn't, I wasn't able to find any traces of freon using the hand held freon meter.

I've left John Davis with a copy of the net2phone software, and it looks like we have another winter over friend there. That's good, it's good to have winter over friends.

Well that's about it, It's going to be a bit of a pity to leave this place, but we're finished here and it's time to go. See you guys
back in Sydney in a few days time.

Regards
Daniel Marlay

UNSW / CARA / JACARA / AASTO person

Contact:

• Prof John Storey: jwvs@phys.unsw.edu.au