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Reports from the Field - December 2000

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Sunday - December 31, 2000
By G. Wilson

I've been wanting to write this particular update for a while. Tonight, I lay it all on the table.

You see, this is the last update of the year 2000 and in the spirit of reminiscing of days gone by, and in light of the fact that TopHat is bound for higher altitudes in a few days, I figure that this is an appropriate time to reminisce about our journey to build the beautiful and nearly flight-ready TopHat telescope.

Truly, this is an epic story. There are heros. There are villains. It's been a long and exciting road. But first, let me fill you in on our environs. McMurdo is abuzz tonight with New Years Eve revellers. The big party is supposed to be at New Zealand's Scott Base - a short walk but long stagger from downtown McMurdo. Adding to the excitement in the air is the arrival of the icebreaker Polar Sea. Each year in the summertime the sea ice north of the Ross ice shelf melts away under the sweltering Antarctic sun. The Coast Guard then sends in an icebreaker to cut a shipping lane through the remaining thin ice to McMurdo. Following the icebreakers are container ships from the US bearing next year's food, heavy equipment, and fuel. Also tailing the icebreakers are killer whales looking for yummy seals and penguins along the Ross island coastline. In fact, Jim has a nice postcard of a whale breaching in the sound just off Ross island ... yet another reminder to keep your toes out of the water!

So TopHat has been a long time in the making. Like most innovative projects, the original experiment was actually designed to be quite different from what we have now. Instead of an on-axis spinning telescope, we started out with a small telescope designed to point at specific points in the sky. Fortunately, during the "pointer" development, the thought arose to build a much simpler telescope that spun at a fixed speed on a fancy lazy-suzan. Thus, the TopHat-Spinner was born.

I personally joined the project in the fall of 1997 with the directive to move to Chicago where the top package was being worked on by the vastly experienced Steve Meyer and two graduate students (Tom and Jeff) who were wet behind the ears and itching to be bossed around by a young postdoc. What a fall. The three of us, with help from Casey Inman at GSFC and a lot of guidance from the older folks, built circuits, cables, and sensors and eventually integrated the top system's electronics - the same set of electronics that are at work acquiring data as I write. As we cranked on the electronics, Dale and Eun continued work on the nearly miraculous Indigo dewar and Tina Chen slaved away over acid baths and implanters to build our ultra-sensitive detectors.

The spring of 1998 brought a new challenge for the Chicago folks. NSBF was interested in launching a mockup of the top package to investigate the launch and flight dynamics of a 250 pound top-mounted payload. Tom, Jeff, and I were asked to build a small instrument to fly inside the mockup and deliver temperature, pointing, and acceleration data to the payload hanging below the balloon. This was a new experience for all of us but with a great deal of luck and a spring spent travelling between Chicago and Texas - punctuated by 5 or six high speed, high volume, drives on the open Texas highways at 3 am, we managed to pull the flight off.

I was the beneficiary of two frequent flier tickets on Southwest Airlines due to the incessant flying between work at home and work in the field. Man was I sick of peanuts. You can see a movie of the launch of the GSFC built mockup on this web siteour web site. Our travel experiences, we were soon to learn, were only just beginning.

In the fall of 1998 we shipped out again for the LDB qualification flight of our bottom gondola - this time to Fort Sumner, New Mexico. What a beautiful place. Fort Sumner is located in the desert west of Albuquerque. I haven't spent much time in the deserts of the southwest so, much like my current trip, I soaked up the scenery while we prepared the TopHat bottom gondola for launch. This time we had great help from the actual builders of the gondola: Bob Silverberg, Ken Rehman, Joe Novello, and John Stewart - all of GSFC - and once again we enjoyed great luck and had a successful test flight. I'll always have good memories of that Fort Sumner trip. Jeff and I learned about the fine art of surveying and Tom learned valuable lessons about hand carrying a set of duct-taped batteries through airport security.

It was around this time that my soon-to-be fiancee asked me if most physicists travel this much for their work. Of course not, I assured her. With two successful launches under our belts in 1998 and the addition of James to our posse, we were due for some serious karma payback in 1999. And pay we did. Nearly the entire year was spent trying to diagnose a particularly insidious and subtle thermal problem with our rotation system while sequestered in Goddard's building 7. Despite the 35.25 years of experience we had helping us, we somehow survived with our egos only slightly bruised and our attitudes firmly intact. What is truly amazing about 1999 is that any of us ended the year still dating our beaus after spending so much time away from Chicago. That includes Dave Cottingham who originally had graciously offered to let us sleep in his house for a few weeks. Those few weeks eventually grew to months and months and Dave, being the gentleman and scholar he is, never so much as blinked.

The year 2000 arrived with the Chicago crew back in Chicago for a brief chance to collect our breaths. We solved the rotation problem with the timely purchase of a restaurant meat locker big enough to cool the entire top package, beautiful detectors arrived from Goddard and Wisconsin where they had spent 1999 struggling to overcome a nasty problem with their detector-building setup (it was a bad year for everyone!) and Dale and Eun put together the first long-term working Indigo dewar. But home life was not to last long for Jeff and James who, with steely eyes and a bulletproof drive system, went back to the thermal chamber at Goddard to face another two months of integration and testing. Tom and I, busy building more Indigo dewars at Chicago, later joined them for a few weeks of beammapping in the Goddard anechoic chamber.

At this point we were entering the final stretch so spirits were high. Nearly the entire TopHat collaboration met up in Palestine, Texas for our pre-Antarctic integration and shipping of the telescope. Tom, Steve, Jeff, James, Bob, Ed, Dale, Eun, and Dave spent nearly the entire record-hot summer in Palestine while I stayed behind in Chicago to build yet more Indigo dewars. Work in Texas went amazingly well with only one blown up dewar (which was quickly repaired) and, a collaboration first, no trips to the emergency room on the fourth of July. When it was all over and all our equipment shipped out for the ride to Antarctica, we all breathed a collective sigh of relief. One more trip to GSFC for beammapping and $75 spent at Wallmart for Antarctic supplies later, we were Antarctica bound.

And here we are, on the eve of a new year and (metaphorically speaking) a new launch. It's been a long and interesting trip so far. The next few days promise to be interesting and exciting as well. We've learned a lot, laughed a lot, and quite miraculously have suffered no divorces in the meantime. Thanks to everyone who has helped us get this far. We're bringing it into the home stretch now so keep watching and keep rooting. We're working hard to ensure that 2001 begins with a ... well, a great launch!


Friday - December 29, 2000
By G. Wilson

Greetings from the deep deep south once again. I am in a particularly good mood this evening because I am writing with a clean set of clothes, a generally clean outer layer of skin, and a slightly dirty coffee cup that's filled to the brim with hot Peets.

Never mind that TopHat is in particularly good shape as we round out our pre-integration testing, it's really the simple things that make the biggest differences. Are we going to continue to count down the days until our launch? When will that be? It's a bit difficult to say.

We have gotten most of our testing out of the way now - there are still a few left to do - and we are nearing the time when we will begin integrating the telescope with the balloon. Once we declare flight-ready, it is the weather's will that determines when we launch.

Speaking of the weather, we were privy to witness a beautiful sight yesterday. The ATIC package, the other ballooning group down here, was launched yesterday evening at approximately 5:30pm local time. The launch was simply amazing. The day started out and continued to be completely overcast. I had even seen some snow flakes in the morning before their roll out. Well, that didn't stop them. Around 4:00pm we walked out to the launch pad and stood in the chilly wind as they blew up the balloon. The clouds and snow provided very little for contrast as backdrops against the balloon so if you took your polarized sunglasses off, the bulk of the operation nearly disappeared from view.

The ATIC experiment on the crane prior to being taken out to the launch pad.
Checking the balloon prior to inflation.
The balloon in the process of being inflated.
The balloon just after release.

After nearly an hour of inflation, the spool capturing the base of the balloon was released and the bubble made a quick jump into the very still low level winds. Like all balloon launches I've seen, it was quite beautiful. The balloon resembled a very large jellyfish as the helium pushed in waves against the balloon material and it seemed to climb into the sky much like a jellyfish swims to the surface. Finally, after what seemed like minutes, the balloon was over the launch vehicle holding the payload and the gondola was released for its voyage around the continent.

Fortunately for us, there was a fairly low cloud cover which made for a memorable scene as first the balloon and then the gondola slowly disappeared into the puffy grayness. As I understand from the local gossip, the flight is going well and the balloon has so-far held a roughly fixed-latitude course.

Back on the TopHat front, tomorrow we hope to move the lower gondola over to the lab space the ATIC team had occupied. This will allow us to spread our elbows a little and get our solar panels mounted up for a power test. The top system will spend another day here in the lab while some finishing touches are made on the light shield. That's it for now. Check back often for my "Ode to Stalagmites" audio file which will be done in two part harmony. I'll be doing the number one part.


Tuesday - December 26, 2000
By G. Wilson

Happy Holidays!

Every once in a while I like to remind myself why I'm here. Of course on the surface I am acutely aware of it, since I see and touch TopHat every day. But every so often it's healthy and useful to think through the chain of events that has brought us to Antarctica to do this experiment.

For those who read these updates to find out what's going on down here (a dubious proposition indeed given what I've written in the past), I'll devote a paragraph to our status first. For those who are just looking for the latest gossip about our younger team members, you have come to the wrong place... of course, I'll be delighted to tell you in private though!

Overall our flight preparation is continuing very positively. The cryostat is cold once again in the flight configuration after our successful noise testing and the telescope is in the process of being buttoned up once and for all. Luck was with us today and the weather cleared, allowing TopHat to be once again outside on the berm spinning.

This test was necessary after the last spinning test revealed a partially occulted sun sensor. Fortunately this was very simple to remedy and we are now getting the cross calibration data with the various sun sensors. I should also mention that this test is being done with the main rotation bearing in its flight-lubricated state. Jeff spent nearly all of Christmas day and Christmas eve putting the bearing into its flight configuration and buttoning up the stationary part of the telescope. We'll have to make sure he gets an extra orange in his stocking next year!

Now we find ourselves with flight day rapidly approaching. I won't deny that everyone is starting to get a little fire in their belly thinking about the big day. And who can blame them? The majority of the people here have devoted their working lives to TopHat for the past three years. And some have been working on the project for the past six years! After all that time, all the weekends and nights spent in the lab, we are simultaneously eager and apprehensive about the launch.

So, for the remainder of this "update" I want to remind everyone why we do what we do. The big picture. I like to think about this because it makes muscling through the rougher times a little easier. Thinking about our raison-d'etre is also just plain fun. It all starts with a simple idea. We know that the universe is expanding. We also know that if we let a gas in a bottle expand, it cools. Simple thermodynamics. Put the two ideas together, turn time around, and we're led to the conclusion that the universe used to be dense and hot. Both a simple idea and a predictive one (the best kind of theory) because if the universe used to be hot, it used to radiate hot photons. Indeed, in 1965 those photons were measured.

But it was the next idea that opened a real can of worms: if the universe radiated photons when it was young, and we can measure them now, we should be able to infer the fundamental characteristics of the universe by making a measurement of the spatial distribution of these photons today. It didn't take long for the idea to be generated, but it's taken 35 years for us to develop the techniques and technology to make the measurement.

Now to understand TopHat, you need to put yourself in the shoes of some of people who came up with the idea of TopHat in the early 1990s. That would be Steve Meyer, Ed Cheng, Matt Kowitt, Dave Cottingham, and Dale Fixsen. At the time, they were running a successful campaign involving a telescope called MSAM. The details of the experiment are not important but the critical notion is that these were very scientifically conservative people and these were people who understood that they were trying to make a very difficult measurement. This had an interesting consequence with the MSAM experiment. You see, during the three balloon flights of the telescope, the MSAM team was widely criticized for using an ultra-conservative observing strategy. The cosmology community didn't want conservatism, they wanted someone to make an "exciting" measurement that pushed the telescope to its limits. What Steve, Ed, and the others understood, however, was that the *only* way to make a successful CMB measurement was to play it safe. And this strategy has withstood the test of time.

In fact, we wrote an interesting and significant paper in 1998 based on the MSAM data - three years after its last flight! So here were these guys thinking about what to do after MSAM. It was already obvious at the time that what was required was an experiment that covered a large fraction of the sky with very high sensitivity. It was also clear that the experiment had to be designed with the idea that the possibility of systematic errors (environmental contamination, foreground source contamination, etc.) had to be mitigated at all times. After all, these were the kinds of errors that had been the downfall of most other CMB telescope experiments. In other words, what they wanted to design was a conservative experiment. Enter TopHat.

On it's face, TopHat does not come across as very conservative. Number one, it's flown from a balloon and thereby absorbs all the associated risks of bad launches, bursting balloons, and weather related delays. Number two, it flies from the top of the balloon adding yet another complication. And number three, it flies in Antarctica - demanding an experiment that can function properly and reliably for at least seven days at float altitudes. But while a pedestrian might shy away from these ideas, in fact, they have all been done before and the benefits of each to the quality of the measurement far outweighs the risks and vastly *increases* the probability of success. Flying on a balloon puts us above the atmosphere - a dubiously unpredictable and uncontrollable contaminate of ground-based instruments. Flying on top of the balloon gives us a wide and unobstructed view of the sky - vastly reducing the possibility that our signal is coming from the balloon itself. And doing this from Antarctica gives us days of integration time and, coupled with our observing scheme, allows us to make the same measurement of the sky each day of our flight.

How many CMB experiments to-date have had these leisures? None. Until now. So, in case it hasn't gotten across yet, I am excited about TopHat. If it works only half as well as our predictions, we will still be able to hand the world something significant. This is something worth spending the holiday season in Antarctica for. This is something worth being excited about.


Thursday - December 22, 2000 - the first full day of Summer. See how the ice is breaking up!


Wednesday - December 20, 2000
By G. Wilson

The more I hear about the weather in Chicago, the more guilty I feel about being away in Antarctica. Reports include bone-chilling temperatures combined with lots and lots of snow. Here we continue to have temperatures hovering right above freezing and at least part of every day with blue skies and pleasant views of the surrounding mountains. Don't get me wrong though. Warm temperatures aren't all they're cracked up to be. Today I noticed that we have melted our way nearly down to the ice floor below and the path between our lab and the outhouse has turned to slush. I would describe further features of Antarctic life in this heat wave but I would be forced to violate my promises about potty humor. That is too slippery a slope to play near.

We are nearly finished putting the TopHat subsystems back together after our marathon disassembly, fix, and integration. This has been a busy couple of days. Below I'll give you a taste of some of the changes we've made and what results we've seen in our testing today. Overall I should say that we are extremely encouraged by what's happened.

The radiometer was warmed up and opened for two operations: a set of capacitors were placed on our signal lines to dampen the detectors' microphonic responses and a cap was installed to cover our input horn. The cap on the input horn will allow us to work on the system sensitivity in conditions similar to those we will encounter in flight. Frankly, doing this makes the system ultra-sensitive - allowing us to sniff out noise sources and eliminate them. Both operations were completed in a day and the dewar was re-closed and pumped out the same day it was opened. The following day we cooled it down and it is now running with nominal boiloffs and temperatures.

The telescope was also disassembled for some small modifications. RF filters were installed on our motor amplifier, the coupling between the bearing and our top platform was improved by inserting some soft o-ring cushions, the dewar thermal blankets were reinforced and improved, and the cabling was re-routed and tied down in flight configuration.

On a different front, we met with the NSBF folks yesterday morning to go over our launch day operations and requirements. The meeting was very productive (despite my all too apparent lack of sleep from dewar operations the night before). We passed out our schedule of what we expect to happen on launch day and went through it item by item. Amazingly enough, there were no major surprises as can happen when two nearly independent groups make plans which require each other. The most startling thing that was said was that we will do our compatibility tests and if the weather is good, we'll then head out to the launch pad and go for a flight. This is in stark contrast to the way things work in Palestine where the launch opportunities only coincide with dawn and dusk lulls in the wind.

As far as launch day goes, the plan goes as follows. First they will pick up the bottom gondola and drag it out to the launch pad. They will then return and pick up the top package. Steve and I rode on a balloon-laden sled yesterday to test if the vibration from the tractor would rattle the dewar to pieces. It turns out to be a pretty cushy ride (a bit smoother than my Jeep) so it looks like we can avoid the headache of installing the dewar on the launch pad. Once the telescope reaches the pad, we do some tests of the telemetry and commanding and then give them the go for tow balloon inflation; the tow balloon goes up, the main balloon gets inflated, the tow balloon is released, we orient the package in the launch-direction, and then they pull the spool.

I must remember to ask if they will provide anticipation-induced air-sickness bags for the launch. I'm feeling queasy just writing about this stuff!


Tuesday, December 19, 2000: The upper atmosphere winds are beautiful. Any flight with winds like this would make an almost perfect circle around the South Pole.

Sunday - December 17, 2000
By G. Wilson

It is said that winter is the time of year that steels our bodies and minds to the hardships of life. I've always liked a good winter. I like it snowy and bitterly cold for at least a few weeks of the year. I like that it gets dark early and that the snow on the ground and in the trees muffles the sounds of the city. I like that people help each other out of snow drifts and generally acknowledge that we might as well be neighborly because the difficulty of winter is mostly unavoidable. So I was thinking about winter in Chicago today (which I am currently missing) and it led me to ask - am I experiencing winter here in Antarctica ... or is this really summer like they tell me?

Of course we've got plenty of snow, and there are certainly moments when the cold reminds you where you are, but on the other hand there is no escaping the 24 hours of invigorating sunlight and the weather is not nearly as oppressive as it might be. Despite these summer features, however, McMurdo (and to a larger extent the crowd at Willy Field), is a community of people who are bonded by the dangers of the weather and its unpredictability. The winter spirit is alive and well here and it will make all the difference in being able to bear being away from our families next week.

TopHat spun atop the Ross Ice Shelf with tremendous majesty yesterday. At approximately 1:00 in the morning we brought the fully assembled TopHat to our remote testing sight and let it run for 15 hours as the sun rose and circled the package. It was really a sight to see. During that time we acquired the data needed to make a calibration of our sun sensors and our glint sensors. Jeff is working full time at analyzing that data now. As expected we found some small bugs in the setup (we need to lower the suny shade a bit) but they are minor and we are on to fixing them already.

Once the package came home, we met and decided that we are ready to do our final tune-up and assembly of the flight telescope. The euphoria of having the package fully assembled was short lived as we began disassembly late yesterday and returned TopHat to its component subsystems. We are planning two to three days of subsystem configuration followed by the final integration. For this next round of tests, the dewar will be sporting an eye patch at 4.2K and new microphonics shorting capacitors between gate and return of the six low temperature FETs. These have been installed and the dewar is back on the pump in preparation for tomorrow's cooldown.

Yesterday marked the arrival of Hans Ulrik - one of our Danish collaborators - to the lab. Hans Ulrik will be staying through the flight and we are excited to have him around to help with real time flight analysis software. Unfortunately, his arrival coincides with Dale's departure. We will certainly be missing Dale both during the lead-up to the flight and then again during the flight. Dale has a way of thinking about things that is unique to the group. He also thinks fast on his feet and is great to have around in a pinch. He also has an uncanny ability to wear the same cloths 35 days in a row while maintaining body odor levels lower than mine reach on a sunny day. Yes, his talents are multifaceted.For the next few weeks we'll have to learn to take advantage of those talents that are transferrable via email.

In case anyone is worried about us working too hard and becoming dull, last night the TopHat crew (minus our tireless leader but plus Dale!) took the evening off to celebrate Mardi Gras in town. Why does McMurdo plan a Mardi Gras celebration in December? See paragraph two above. I've got to say, it's quite an event when this town throws a party. The celebratory energy that is expended is large and even though there is the unavoidable idiot factor, the town bar was a fine place to spend a relaxing and entertaining evening ... Winter is alive and well in Antarctica. Don't let them tell you otherwise.


Thursday - December 14, 2000
By G. Wilson

Christmas is 10 days away and all I want at the moment is a shower and a meal that has more starch than protein. But what can I say? If I've learned anything from incessant cinema and sports watching it's that you don't mess with a streak ... and a streak is just what we're on. Fortunately, that doesn't mean we have to wear garters (with the rose facing forward). It means we've got to keep working and making the great progress that has characterized the last two days.

TopHat continues to come together. Top system integration is nearly complete now that the sun shield has been added to the fray. Last night we fired up the glint and sun sensors and saw that they are running nominally. Tonight, starting at midnight, we will have a glint and sun sensor calibration run. This involves bringing the top package to the top of a berm (not the one with the controversial third forker) about 200 feet from the lab tent.

The package will then run for 12 hours so that we can calibrate the sun and glint sensors over the entire range of angles we will view the sun during the flight. A large fraction of today was spent working with the dewar and the telescope. The overall system noise when we are stationary is simply fantastic ... ie, it is consistent with what we would expect from calculations. Tests from last night have shown that we likely have some pickup from AM modulation of one of the dewar resonances. A fix has been envisioned and DC will do a bolometer calculation tomorrow to confirm that it is the right thing to do. In any event, we have been plugging away mercilessly and we are confident that we will beat down the rotation-induced noise.

Tomorrow we are scheduled to have prime rib once again for lunch. Okay, this is probably a good sign as far as the streak goes, but the fact is that I've been waking up in the middle of the night yearning to graze in a warm pasture. I remember days of yore when Dale would eat steak after steak in Palestine ... for months on end. I would sit and stare in wonder.

Now here I am in Antarctica and day after day and night after night I eat cow - three meals a day (okay, milk isn't exactly roast tenderloin but you know what I mean). This isn't nearly as disturbing until you remember that this is the *only* continent on the earth where there are no cows! In fact, I was privy to learn this morning that I have yet to eat something here that has not been on this continent for at least 12 months. If that's the case, why aren't we eating Roquefort based dishes or Antarctic kimchi? Such are the things I ponder in the daylight of Antarctica in the middle of the night. This place is wonderful ... but very odd.


Wednesday - December 13, 2000
By G. Wilson

Noise, noise, noise. That's all that comes from the speakers here. Those graduate students have loaded our computers up with loud, inexplicable noise that plays incessantly throughout the day. I keep asking them to fix it. They just look at me befuddled. The best they can do is to stop the DJ from spinning disks. That certainly helps but as soon as they're going again my brain starts to throb. I just can't stand that noise much longer. We really must do something about it. We've tried putting the source outside on the snow and it didn't help much. I am currently planning my next move to get some peace and quiet around here.

The weather, on the other hand, continues to be beautiful here. Today must have been in the 40's - allowing me to walk to the galley in short sleeves at one point. I'm feeling sorry for those poor souls in Chicago who are dealing with -30 degree wind chill and a foot and a half of snow ... especially since I nabbed all the cold weather clothing on my way out the door.

Dave continues to think deep thoughts about the flight software. He has been tasked with making a final review and searching out any small bugs that might lie within. He is finding the task quite challenging and we all should thank him for this after the flight. This kind of detective work is a bit numbing and is quite tedious ... Fortunately, the cook provides a steady stream of sugar in her time-release deserts. This seems to be plenty to keep Dave going throughout the evening.

As I understand it, the balloon group next door is holding at launch minus two days while they try to repair a software problem in their system. The pressure is on now. The Pathfinder (a balloon that they use to measure the wind speed and direction at "float" altitudes) is showing that the high altitude winds have indeed set up in a vortex around the continent just as the ground based sensors previously hinted.

To see the current position of the Pathfinder, check out http://192.149.107.13/ice0001.htm.
To check out the ACLU homepage, go to http://www.aclu.org/

Best to all -


Tuesday - December 12, 2000
By G. Wilson

Yet another day passes for TopHat in Antarctica. Will some find this a depressing thought? I don't think so. Each day we are one day closer to our launch date. Each day we encounter new challenges, overcome old obstacles, and reach and explore our own limitations as both scientists and people. Some of these days are difficult. Some of these days bring great surprises. And some of these days leave us wondering why we ever came here in the first place.

In the end, however, these days before launch carry with them the ever-growing anticipation of the flight, that each of us has felt, for better or for worse, with them since joining the project. Is the first kiss ever as interesting as the 10 minutes before? Rarely ... and in this case I'm betting that it's these days that I will be remembering 10 years from now. Not in detail but as a collection of dinner conversations, tough experimental problems, and writing corny letters home. I'm really enjoying this time.

That being said, I want to announce that dewar B is cold once again! In past notes I have glossed over the idea that we had warmed up the dewar and gone in to fix a wiring problem. Well, as most know, this dewar is made of eggshells. Once closed and working, it's a pretty reliable companion. Inside, my hands feel like 20 pound balls on then end of tree trunks. This dewar is damn hard to work on. Thankfully, due much to the outstanding diligence of Crawford, who slaved away opening and closing the thing for four days straight (two of those while I was off playing at snow school) - disdaining breaks (and showers), we now have a functioning cryostat again.


Monday - December 11, 2000
By G. Wilson

Another busy day for the TopHat crew. The dewar is coming back together quickly and so far it's looking pretty good. I think we've made some fundamental improvements in both the signal wiring stability and the optical alignment. With luck, tomorrow will come the big test where we cool it all down and see if we re-assembled it properly.

Today we met with Victor (the NSBF crew chief) and had a discussion about the schedule of events that will occur on the day of the launch. Somehow, despite the fact that I've travelled thousands of miles to Antarctica after working for years on this project, this was the event that made it all seem very real. What's more, Victor is as gracious and accommodating as we could possibly desire ... clearly not a true government worker. We pounded out a launch day schedule that looks quite reasonable on its face. I will send this out to the balloon mailing list as soon as I get it typed up (typing happens only when I can trick Tom into doing some dewar task that I should be doing ... I've sold him the same dead one-eyed cat four times now and there's no telling if he'll go for it again).

After dinner tonight, Tom, Jeff, and I went outside and snapped some pictures while displaying some Peets coffee. Hopefully I'll get them by the government censors and we can sneak them onto our web site. You see, not only does Peets coffee fuel the TopHat machine, the nice folks at the Peets in Chicago (1000 W. North Ave near the Whole Foods) actually gave us some free coffee and a few thermal mugs for our trip. I'm reminded each morning how much we owe these people. Please tip well if you happen to be in the neighborhood!

Finally, I've promised to not pick on James this update. Jim, on the other hand, has no such immunity. Poor Jim. As I type he is taking a nuclear physics exam in the sleeping jamesway. I just went over to find a spare sleeping bag and found him sprawled out on the floor consulting a magic 8 ball ... oh well, the world needs ditch diggers too.


Sunday - December 10, 2000
By G. Wilson

Sorry about the lack of updates lately. I have been subjected to snow school for the past few days and I forgot to ask someone to take up the typing slack in the meantime. From the progress made during my absence, it's clear that no one was able to take time to write anyway.

TopHat preparations continue. We have been working on re-configuring the cryostat wiring to eliminate a spurious noise source. This has taken a bit more time than originally expected but we hope to be back up and running with our cold detectors shortly. On the telescope front there was a major discovery and quasi-cure of a clocking anomaly in one of our counter circuits. Jeff, Steve, Dale, Renee, and Cottingham all looked into it ... it was a nasty little bugger ... and it's now been beaten down into an ignorable phase slip that happens every few minutes or so.

While I was away at snow school the new airport went in next to the lab. This is an amazing transition. Overnight, a crew at McMurdo effectively transplanted an entire airport about 15 miles - from the decaying sea ice on the North West side of McMurdo to the permanent Ross Ice Shelf on the South East side of town. Willy Field was completely unrecognizable when I returned. There are several new buildings, three C-130 transport planes parked in our backyard, and the entire area has been plowed as flat as the top of my head. It is a very impressive piece of engineering and planning.

Oh, and a warning to those who are imminently arriving. Bring your cold medicine. I don't think that anyone has avoided the McMurdo crud yet. Even my mighty immune system was overwhelmed within a few days of arriving. Lately it has been James and Gwynne that have been struck down (insert speculation here ... and then forget about it ...). If you are soon to arrive at McMurdo, I would recommend taking vitamin C supplements before you get here and make sure that you arrive rested and ready to hold your breath whenever talking to anyone else.


Wednesday - December 6, 2000
By G. Wilson

Folks -
Progress continues. We continue to attack our weak points meticulously and systematically ... well, okay, we're at least hacking away at the problems that jump out at us. Much has happened during the last two days.

We've uncovered a potential bug in the main radiometer's wiring. We've warmed up and are currently in the process of mechanically tieing down the bolometer wires better. This is an extended process since we have had to open the dewar down to the cold plate. As always, however, many improvements have been made to the baseline system that wouldn't have been made otherwise. Is this a blessing in disguise?

James and Jim are staking claim as our amplifier gurus. These guys knuckle down and do the really hard and fragile soldering for amazingly extended periods of time. I'm concerned for both of them and their vision. This work involves a lot of staring and sharp focusing on small objects. Fortunately, our post-dinner incessant ABBA playing has encouraged Jim to take a break and go for a snowmobile ride. James, on the other hand, is swaying in his seat to "I Have a Dream" as I write. God bless Sweden.

We are told that the airport will soon be moved to Willy Field. We are all looking forward to this as it means there will be a half-hourly shuttle service between the lab and McMurdo. This will, hopefully, encourage us all to take more evenings in McMurdo and find a bit more time to relax ... or at least get a shower ...

I did forget to mention in my last update that Dave and Bob have successfully orchestrated an observation of TDRSS data via an actual TDRSS satellite. Congratulations! This is a noteworthy milestone since it demonstrates that we have the capability of getting our in-flight data back from the telescope in real time.

Finally, a slightly sad note. After a day of working on getting dewar Y cold, which it did (!), Dale and Eun discovered a small helium leak in the top of the main helium dewar. This is a particularly ugly guy since it seems to leak liquid helium much more efficiently than the gas. It wasn't a problem until they filled the helium tank entirely and the dewar went soft. This is a small setback but at least it's only the backup dewar. Our plan is to get on trying to locate and fix this leak tomorrow.
Cheers -


Monday - December 4, 2000
Raytheon Polar Services Company Update
By Bill E. Haals, McMurdo Station Manager of Operations

Good Morning McMurdo & Scott Base,

It is that time of the year for the annual move of runway systems from the sea ice to the ice shelf. For those of us that have been around this marks one of the biggest milestones in the season, more or less the half way point and also the time we change the way we have been doing business.

Travel to Williams Field is on the snow road. The snow road is just that, a snow cover over the ice shelf approximately 25' thick. The ice underneath that 25' of snow is a couple of hundred feet thick floating on top of 1800' of water. That is your road surface lesson for the morning. Next lesson is how we deal with this unique road, especially this season with all the new snow that keeps falling on the compacted sections.

The snow road is made up of 4 lanes outbound to Williams Field and the same lanes for return. 3 of which are for wheeled vehicle traffic and one for tracks and chevron tire Deltas. One wheeled vehicle lane at a time is open for travel. The road itself is under a continual compaction by heavy machinery pulling a variety of compaction equipment. The road will fall apart if it is not respected and certain rules must be adhered to.

As most of you know the new fleet of trucks are not equipped with tires that are made for this kind of environment. Even the ones that do have the flotation tires are not traversing the snow road as they should. Why? This is a very heavy snow season and the compaction of this road just keeps getting covered up with new snow. We need to cut back the amount of vehicle traffic while still keeping the system operational out at Williams Field.

Come Saturday, the day the Ice Runway is re-located to Williams Field only flotation tire or tracked vehicles are allowed to Williams Field. The day of the move there are some allowances to get needed vehicles to the skiway for the construction of the airfield and those to be stationed out there for the airfield but after that we have to limit the amount of traffic and rely on the Shuttle System and whatever else we come up with. This includes aircraft parts re-supply and AGE resupply, you will need to rely upon transportation using flotation tires or tracks. Some of you are going to ask how you can get your jobs done by not being able to drive back and forth all the time but you can be innovative. For aircraft & AGE parts those can be brought from town to the transition, placed on a shuttle or a flotation tired vehicle and taken out to the airfield. The same goes with a lot of other needs. We do have some rims for flotation tires and lift kits on the way that we will be placing on certain vehicles but until that time you are going to have to rely on other means.

For those of you using the snow roads there are a few rules. The road is being compacted as best as possible but between the flag lines it is not compacted in any way shape or form. If you cross between the flags you will get stuck driving a truck no matter what kind of tires you have and then you get to meet one of the operators with heavy equipment - that just might bury you deeper and keep going. The faster you drive on the snow roads the more your vehicle will tear it up and the faster it will deteriorate. Go slow. Also scrape (I didn't say "beat") the mud and dirt out of the wheel wells before driving onto the snow, a barrel with wooden handles will be available for that use just before the Scott Base transition. Dirt hastens the melt of the transition.

The snow road is your means of accessing Williams Field and it is up to you to keep it in the best shape as possible. Just think what is going to happen to it once this snow starts to heat up and melt...


Tuesday, December 4, 2000
By G. Wilson

Another day closer to launch for TopHat. During today's meeting with Steve Peterzen from the NSBF we were shown 3 mbar and 4 mbar surface wind plots for the continent. They are beautiful! The center of the vortex is right over the south pole and the wind lines were all nicely tangential to lines of constant latitude. In fact, Steve says he hasn't seen it set up this early and this nicely before. More to the point, he said, "Well, if I were flying an experiment this year, I'd want it to be ready for flight sooner rather than later." That officially makes two of us. NSBF will be putting up a sounding balloon at the end of this week to see if the upper atmosphere winds have set up as well. After all the travel problems it caused, the weather may be starting to smile on us after all!

A lot of dewar work went on today. We have explored the dewar hold time as a function of the dewar tilt and now have some new knowledge on the flow dynamics. This is a nice step forward. As Dale's note today said, we have also put LN2 into dewar Y (the backup dewar) and we plan on cooling it the remainder of the way tomorrow. Finally, noise testing continued on dewar B and we determined that it has more microphonic (vibrational) sensitivity than we would like. We'll most likely warm it up overnight and attempt to search out that bug tomorrow.

I also saw Tom and Jeff milling about the telescope and I'm not sure James removed his head from inside one of the amplifiers all day. As promised, Tom has found the root of the problem with the GRT readout and has fixed it. As I understand it, a significant amount of cable fixing and patching also got done ... all small jobs that tend to stack up. Kudo's to those guys who hammered through them!

Now to correct a mistake from my note yesterday. When I first arrived to McMurdo it was a condition 3 day ... not a condition 1 day (which would have been quite difficult to land in!). Thanks so much to those thoughtful souls who informed me of my slip-up. In fact, I liked the bevy of responses so much that I think I'll slip in at least one lie into each update I pen. I'll leave it as an exercise to the reader to sniff it out.

By the way, it was steak for dinner again tonight. I personally saw Cottingham and Crawford eat nothing but salad (no dressing) and water. Tom was heard to say that his days of multi-big mac eating are behind him ... so to speak.

Wishes of warmth to all -


Sunday, December 3, 2000
By G. Wilson

Greetings from the Ice.

We've had a slight swap of responsibilities. Ed has headed back to warmer climates and has handed off the torch of update writing to yours truly. I pledge to reduce the potty references ... but only after expressing my deep regret for not bringing potpourri as Eun had requested. This was a true mistake.

Last night Dave, Alex, and I came into town to find a beautiful condition 1 day with low winds and the temperature hovering just above freezing. While making it quite comfortable for sightseeing and acclimation around McMurdo, the warm temperatures had the unpleasant effect of turning McMurdo into a volcanic swamp. Unfrozen, McMurdo is actually quite yucky. The big trucks (with BIG wheels for getting around in the snow) tend to make large ruts in the soft road in the absence of ice. After the thaw, these ruts are filled with black mucky water - making us all glad we were sporting our huge ECW boots which we had all been grumbling about carrying around just a day before.

Ed must have worked hard while in town because he never mentioned the various activities available to McMurdo's citizens. From my count, McMurdo has two bars (one smoking and one non-smoking), three gyms, a coffee bar (where they also serve wine), and a bowling alley. Rumor has it that all the alcohol in McMurdo mysteriously disappears when the ice breakers and their rambunctious crews come in ... go figure. In any case, as I understand it our younger folks have not had trouble keeping busy while the old farts spend their night in the lab. I'm still working on figuring out which side of the fence I sit on ...

As far as progress goes, dare I say that things are going quite well. The dewar remains cold and Dale and I have been working on fixing a bug in the hold time software. We think we have a handle on it. As far as the remainder of the package goes we have decided to spend some time servicing the top payload. The hope is that over the next day or so we can get the amplifiers buttoned up for more noise tests, the GRT readout reading out again, and the package buttoned up in a flight-like manner for more noise testing.

Finally, I must report that McMurdo, or maybe it's the snow, or the sun, or something ... whatever it is, something has had an effect on the people of TopHat. It all started with a hot nickel. Now I am hearing rumors of indecent snow showers under blue skies and Korean moons flashing in the night. Tom has a beard, Jeff a mustache, and James got a haircut ... as far as I know, Alex's hair is still brown and covering the majority of his head.

I think I'll be sleeping with one eye open tonight.

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