Antarctic Astronomy Winter Diaries 2003/04

   

   

Sunday, January 19, 2003

4 by 10

Hua-Bai and giles installing the template inside ACBARThere is not very much to say about today. The aligment of the optics is still going. We spent another afternoon and part of the night on that little nest inside Viper. Each movement, inside that tiny place, has to be made with great care to avoid to damage the chopping mirror, joint to the telescope by two little and fragiles pivots, designed to minimize microphonic noise (vibrations that induce noise in the detectors). After climbing several times into the telescope, Hua-bai carefully insert the template between the optics. If the mirrors are in the right position to send the radiation, with minimal distortion, toward the detector. We haven't very much time to spend outside. The effect of this strong cold on my body used to the Sydney beaches

Perhaps surprisingly, you can touch the mirrors and even lean on the primary mirror. Actually, one of my more common tasks during the winter will be to remove snow from the mirrors. This will not be accomplished by use of delicate and hi-tec instrument, but by mean of a broom, a normal broom, exactly with a common millet. The trick is that, unlike optical telescopes, this telescope is designed to collect radiation of pretty large wavelength, large as much as a couple of millimeter. Radiation at this wavelength can't see the roughness at the surface of the mirror. It is something like if you are bouncing a ball on a rigid net spaced at a distance much lower than the size of the ball. The ball will not see the fence, neither will pass throug it, but will be simply bounced.

And so, also pretty large scratches will not perturbate the reflection of the radiation.

Hua-Bai working at the template in the CARA workshop at South PoleWe go ahead till pretty late in the night. I'm pretty hungry after some time spent outdoor. After that I got into the dome and sit down in the galley. The galley of the station is a bit worn, but actually is really warm. You get in, and you find always some people with reddened nose chatting and eating something. From the speaker comes out a music, usually pretty good pop, but also classic, sometime. When you are unlucky you get some american country music. Sorry, mate, I really hate the genre. You can serve by yourself, or just drink a tea, or a cold drink, and read a book, on a corner of a table, watching the door to just see who is coming in and who is going out. A row of heavy garments and an assortment of googles, gloves, jacket, is waiting for in an apparent big mess on a row of hangers. The station is so large, and the number of people spout out from the LC-130s every day is so large, that there is always someone new to see.

If I should tell you how, I don't know, but there is always a way to start chatting with people sitting around you. A comment on the food, a person that introduce you to the others, an argument you know. Most of the time you start asking about jobs and related matters. It's really interesting to get into each personality, trying to find out a scheme to classify the others. Most of the people here comes from Denver, where Raytheon Polar Services, the Company that manage the US logistic in Antarctica is based, but you can find people coming from any corner of that country: Wisconsin, Wyoming, Alasca, Florida, and is involved in the maintance of the station or in the construction of the new one. Soon or later the discussion will move about the two fateful questions: are you wintering? how many time you have been in Antarctica? The way in which people approach to the question is pretty interesting. Is like some of those esotheric dances practiced by bird in If you are here for your first time you look at your interlocutor with a shiny glance, like if the fact of being here for your first time is something really unusual and peculiar. If you have been here, we say, 10 times, you tend the trap, asking as the first, and waiting that the other, that just told you that has been here for 4 fatty times. Than you wait for the same question and you calmly say your ten times, looking a point far, and continuing to chewing your potatos like if coming to Antarctica 10 times is the most normal thing of the world.

Suddenly, you stand up, get dressed with all your garments, in the proper sequence, open the inner door, open the outer door, and throw yourself in the labyrinth of dark tunnells that will bring you at your place.

Saturday, January 18, 2003

SPARO

Myself pretending working on the ACBAR. Actually it's all an act for the diary...As I wrote in the past, 2 different detectors have been manufactured for use on the Viper telescope: SPARO and ACBAR.

Today program was the alignement of the optic in preparation of the installation of the first of them, SPARO. So, we had to spent another day mostly outdoor, manouvering screws, that means no glove for long periods.

The VIPER telescope is not a "standard" - that is "as you imagine it" - telescope. A 2.1 m primary mirror, in Aluminum, send the radiation collected from the sky to a secondary mirror, with a pretty fancy bean-shape (not a mistake: I want to say bean, not beam!).

The radiation is than reflected to another mirror, the "chopping" mirror. The main characteristics of this thertiary mirror is that it can oscillate, allowing to look at different points in the sky, at same elevation. This is the more delicate part of the telescope. It allow to subtract some important contributuions to the noise, the "enemy" of the scientist.

The movement must be achieved without any vibration, in order to minimize the so-called "microphonics", a noise introduced in the signal from mechanical vibration. The chopper mirror is pretty large, something like 80 cm in diameter, has a structure in aluminum honeycomb, and must "chop", that is oscillate, at a pace of about 2-3 times a second. Given the large mass, you can imagine is not so easy to obtain a fine "square wave" oscillation, as required from SPARO that is: look at one point, and than move as fast as possible to another point 1.5-2 degrees apart in the sky, stop there for a while, and then get to the original position, and continue forever.

The radiation reflected by this mirror is than reflected to a 4th mirror, called condenser, that send it directly into the window of the SPARO and to the detector.

Giles checking something on the SPARO during coolingTo minimize "aberrations" in the image, all these optics must be carefully aligned. This is made mainly by the use of a "template" in expanded foam, realized by Hua-bai, a Taiwanese student working with Giles, very good in optical computations, that copies the exact distance between the secondary, the chopping mirror, and the condenser.

The chopper must be moved forward and backward, tilted, raised, rotated, till it fit into the template shape. This requires tons of adjustment, untightening screws, screaming, blasphemies, while the nails became purple, some parts of male body disappear lost in the slips and all the body get to shake violently for the coldness.

Meanwhile, the telescope is protected by the sun light and from the one reflected by the ice, that could affect the measurements. This means that the temperature inside the telescope looks also lower than the one outside (-34 C, today), and you are embedded in a grey shadow.

After climbing on the structure, passing through a tiny trap door, pushing on a metal plate to raise you up in a tiny space between the primary and the secondary, you are now floating at about 15 m above the ground, touching continuosly metal parts, that suck constantly heat and heat from your body, and pretty often you have to remove the gloves as you can't actually tighten little screws dressing them.

At the end we discover that, to achieve the correct focal position for the SPARO, we have to partially dismount a protection for an optical encoder (that measure the position of the chopping mirror) and made it thiner in the lab. This take to me a little bit of time, not enough to get warmer. And so, after a quarter of hour, Giles, Bob, Hua-bi and me find us once more time in the cold, battling with templates, screws, frozen tools, etc.

For most of the day we go up and down the telescope trying to obtain the right alignement of the system.

After dinner we restart for a while, but than we decide to get back to the station. It is Friday night, and you can see the first signs of the incoming weekend. At about midnight Giles and me decide to take a look of the galley, drink a hot camomille (me only) and heat something. It is the time of the socalled midrats, when the workers of the new station on the night shift get to the galley to take their lunch. With a face reddened by the cold, dirty and worn overalls, layers and layers of garments, they come to eat something cold. Tonight chicken Kiev, that I bite furiously alternating it with chocolate cookies, while drinking my herbs. It is time to get to sleep, but I still have to chat with my love by my wireless connection from Room 6, "Fred Hypertat", Amundsen-Scott Station, South Pole, Antarctica.


______________________________________________________________________________
Paolo G. Calisse - VIPER / AASTO 2003 winterover
Amundsen-Scott Station, South Pole - Antarctica

Take a rest! Visit my web page at
http://www.phys.unsw.edu.au/~pcalisse

More fun? Read the South Pole diaries at
http://www.phys.unsw.edu.au/southpolediaries

Dilegua, o notte! Tramontate, stelle! Tramontate, stelle! All'alba vincero'
Disperse, o night! Set, you stars! Set, you stars! With the dawn I will win!
The Princep, [G. Puccini, Turandot]

Friday, January 17, 2003

a cool story

The first day without Bill and Mike ran out pretty quickly and busy. We are now cooling down the SPARO detector, the polarimeter that will be installed on the telescope on the first day.

John Schutt, ANSMET (Antarctic Search for Meteorites) showing a meteorite collected in a remote field in AntarcticaThe procedure of cooling down a cryogenic detector is pretty difficult and takes a long time. A cryogenic detector can mantain its ultralow temperature (0.3 K, in this case) due, first, to the use of the best insulator of the world, that is the vacuum.

A bottle in which you can pour liquid Helium, the element with the lowest liquefying temperature of the world, is kept suspended inside a jacket of vacuum. This bottle is usually called the Helium bath.

But this is not enough. Helium, the "standard" Helium, the so called 4He, liquefies at about 4 K, that means about -269 C. To reach lower temperature you have to use by far more complex procedures.

One of the most common, because it doesn't introduce very much noise, as it amazingly doesn't containing moving parts, pumps, engines, etc., is the use of charcoal. Yes, the same material used to burn meat in Australia in the socalled BBQ, and gifted to the Italian kids not behaving good by the Befana, a popular Italian witch-like personnage visiting kid's home on the night between the 5th and the 6th of January. Parents attach socks to the chimeny flue, and kids find them filled with candies, little toys and other little things the following morning. If they have been good, of course. Otherwise they just receive charcoal.

Ok, the charcoal used in cryogenic pump is not the same like the one usually gifted to me almost every year by the Befana, when I was a kid, but almost the same. The reason for using charcoal is that this material, or at least some good, pure charcoal qualities, crumbled in little grains, has the strange property to absorb Helium (actually, also any gas), lots of Helium, when cooled, and release it when heated. So, if you build up a sealed pot containing some Helium, and you attach it to another pot containing charcoal what happen is the following.

You heat, by a little resistor, the charcoal. All the Helium is expelled from the charcoal and move to the pot. When there is no more flux between the pot and the charcoal, you close a valve between the charcoal and the Helium pot, and cool the last one down to 4 K, putting it in thermal contact with the liquid helium bath, by, for example, a thermal contact that can be removed using a sort of movable contact.

The Helium in the pot liquefies as it is now at about 4 K.

After the temperature has stabilized, you open again the valve, and the Helium will start to move toward the charcoal to be absorbed again, because its temperature is now very low, as the charcoal is in contact with the Liquid helium bath, and the resistor has been switched off some time ago. And now the magic.

When you aspire the vapour over a liquid's surface, its pressure drop down. I will not spend more time telling you why. Anyway, when the pressure over a liquid drops down, the temperature of the liquid drop down as well. So, at the end you obtain to drop down the temperature of the Helium in a magic like the one that bring candys into the kids socks of Italian kids, at expenses of parents' pocket. As a general rule, nothing for nothing. Think about that.

Ok, I have to tell that I simplified by far the process. In the real thing, many other devices and techniques are used, and I cheated on some details to make it simpler. In particular, also another "isotope" of Helium 4 is used, that is Helium 3, that has the property of having a liquefying temperature even lower, about -273 C, only 1 celsius degree above the absolute zero, that is the lowest temperature that can be obtained. And this is still not enough when you want to cool something down to less than this temperature, like in our case (0.300 K) that is obtained using the same process in series and pumping over the 3He pot.

Well, I challenge myself to find someone that could understand a word from what I wrote above about cryogenic detectors. In any case, at the end, all this process, when you part from ambient temperature, requires several time to be accomplished, and must be repeated every few days, when the temperature of the last 3He pot has raised up again.

The question, of course, is why you need to cool down a detector to such a ridicoulously low temperature. A quick, simplified reply is that temperature means energy, and energy, when disordered, means noise. And we don't like too much noise in our detectors, when, for example, we are trying to measure the temperature of the Cosmic Microwave Background with an accuracy of 0.008 K from several billions of light years away!

That's it. That's how Giles and me spent all day, in front of the dewar, in a dark laboratory in the middle of nowhere, writing down periodically all the parameters read on a variety of instruments, protesting as soon as the values read were not the expected one (that is normal in this kind of exercises), inventing a lot (wront) different theory about why things were not going as expected, discussing copiously if the reading on a pressure gauge was -10 or -10.05 in Hg (mercury inches), cheating with ourself as you can't really appreciate such a difference when the notches on a pressure gauge are separated by a unit.

But that's the life of a scientist. Never trust us...

Thursday, January 16, 2003

negative publicity

Someone says that South Pole it is no more the same, but let me say that send a message to the internet, comfortably spread out in my bed at the following address: Room 6, Hypertat Fred, Amundsen-Scott Station, South Pole, Antarctica.

If you could have a look into my room you would see the following picture: me in the bed (ok, not such a kind view), at latitude 89 59' 00" S, longitude unknown (my leg have at least one more degree of longitude than my head). 3,200 m of altitude. Connected by a wireless connection to the internet, I'm amiably chatting with my wife located in Sydney. Around my head an headphone, the sound of Pavarotti's voice crossing my skull and being absorbed by a moderate amount of soft material.

What we are chatting about is not your business. Anyway, at once I have to check my bank account because my wife said me that COMMONWEALTH BANK OF AUSTRALIA NEEDS A MONTH, A FULL MONTH, to claim an overseas check, and a WEEK, A LONG WEEK to obtain a wire transfer, like if the wire was tied to Pluto. I quickly connect to the bank web site by my internet browser, log in, and check the statement. I get back to the chatting program and tell her which is our balance. From year, from the South Pole. Isn't it amazing? The Puccini opera has expired, exactly like our money, and I'm now listening to the Beatles, Abbey Road, while a truck is hopelessy moving snow in front of my window for completely unknown reasons, making a lot of noise that I can partially suppress with my noise reduction headphone.

I get a digital picture of what I can see by the window and send it to my wife that can see it almost istantaneously. The picture pass through the server of the station by the air, go to the MARISAT antenna, a big 8 m large dish, and fly to a satellite orbiting 36,000 Km over the equator, got back to some unknown receiving station in an unknown country of this planet, and through wires, routers, wires again and who knows whatever else, get into the modem of my PC back home.

Now, the first question is: isn't it amazing in what an incredible world technology brought us?
Second question: isn't it amazing that all this technology affected all the world except, perhaps, Commonwealth Bank of Australia?

Today it has been a very long day. Bill and Mike, a PhD student, left at about 12:00, and I spend all the day and all the night with them. Now, GIles, Huabai-li, and me, got now a bit relaxed. Looking at Bill leaving is a bit like the first step into the long Antarctic winter. I don't know when and where I will see him again. We have worked hard to prepare everything for the winter, tune up the telescope, adjust minor problems. He and his student, Mike and Martin, that left a few days ago, poured an impressive amount of information into my brain, about how to run the telescope and the ACBAR detector along the whole winter.

For example: to move to elevation -32... let's see... (to make elevation and declination appears similar, the programmers added a negative sign to the telescope, like if we were at the North Pole - end of the note for the astronomers) I have to press F9, than press F10 and check that the word DISABLED appears on the tracking monitor. Than press the emergency button to stop the tachos, that are not a mexican dish, but the amplifier that actually drive the 4 motors (3 for the azimuth and 1 for the elevation). Now... now... well... I have to input the current azimuth and elevation -46. Turn on the main control switch. Disable the 3 azimuth motor. Enable the elevation motor. Release the BRAKE power supply. turn on the COARSE ACTUATOR power supply... Oh...gosh! I forgot I should first check for the position of the gangplanck on the roof!

Big trouble...I will never be able to do all the 3,392 operation needed to move the telescope to the right operation in the proper sequence...

Wednesday, January 15, 2003

Breakfast

What really is the South Pole station? Sometime I ask myself this question.

Well, hard to say, but it is a place where to think is easy. It is a place in which you are waived by most of the duties of your everyday life. What remains is just your job and some very basic needs. Try this exercise: try to keep trace of the time spent in traffic, paying bills, organizing your home, looking after your children. Subtract it from the 24 hours. What remain is probably what you want more from your life.

But is also a place on which you can think everything is upside down, where there is no earth and no water, no green and everything is unnatural.

I'm reading an amazing book from a Pakistan author (I like different cultures), a book plenty of passions, children, traditions. Well, South Pole is just the opposite of any "natural" culture. There are no births, no people growing and slowly getting elder. There is nothing like traditions, except for some repeated operations performed every day, hand down each year from one person to the other. There are no army, no violence, no police and no economic difference. What? A socialist community in an american station? Well, in some sense...

Pretty often If I think to my stay to South Pole as a travel, I'm puzzled, because I will spent my next 10 months in an area long about 1 km and large 100 meter, no exceptions, as never happened in my life. So, it is probably more like a mind travel than a real travel.

So, let's start to tell you something about the real life. This morning I started my long work day at about 7, removing an heavy cover that don't allow to the ubiquitous sun to get into my cubible in the Hypertat. I like this operation. I like the sun, and, so far as I can, I want to have a chance to see it and how he try to draw colours on the surrounding environment. After cleaning up and all that kind of things that I suppose you can immagine by yourself, I got through the double door and move toward the station. This is a half chilometer walk, looking around in the incredibly bright air to recognize almost familiar shape: the LC-130 running its 4 propellers at the airport, the blue building where, I suppose, plenty of people is still sleeping in the darkness, and the unexpected view of the new station coming up day after day. Antenna, strange and unlikely building are spread out everywhere. On my side, an ordered displacement of Jamesway tents, and the huge berm, in which all the material "ok to freeze" is stored.

The hands start to give me some pain, as I use to walk without gloves, now, to get used as fastest as possible to the conditions I expect for this winter. After a little walk downhill I get into the mid of the 3 big metallic archs that are the first step for the new station. They are large (something like 30 meter diameter, about 100 meter long) arches accomodating the garage, the new power generator and a storage building. You walk in the space left free by this building to get into a dedalus of galleries that bring you to the Dome, still the "core" of the station. These galleries are what would you expect from a sci-fi movie, with huge pipes and a large quantities of cables running on each side. The ground is just snow, pretty dirty, but you can still recognize it as snow. Sometime you see someone getting toward you and exchange with him an almost undetectable sign, a quick "hi", or a longer "good morning!" with associated free smile. It depends on how do you fell in that moment as it is pretty difficult to recognize the other as we are all dressing heavy garments and we are surrounded by the darkness. After arriving at the dome, you see a bit more activity. The Dome is a large construction and has been described several time in the past year diaries. Anywhere, it is worth to remember how is made.

It is a stainless steel half sphere, almost covered by snow by now, after 20 and more years since its construction. The floor is just snow. Some sunlight get into from 3 holes on the top and is reflected by the steel, that draw it with a grey, pretty sad aspect. Three two-storey red buildings, made of shipping containers joint together, are spread out into it without an apparent logic. In one there are a computer room and some offices at ground, winter accomodations on the first floor. In the second some services (a sort of post-office, a little store of memorabilia on the first floor, and the comms room at gorund). In the third just the galley, the kitchen and a sort of pub/smoking room.

You get into the third one by a butchery-like double door and leave your heavy garments on an hook. Inside, you are welcome by some music, usually pretty happy at early morning. You collect the dish, the glass, the fork, and try to find something you like to eat. There is a pretty large selection. For what is my concern, I forget about mushroom, tomatos, sausage and eggs - not for me, thanks - and try to find something in a pretty large collection of cookies and cakes. Some of them, I have to say, very good.

I fill my glass with an early gray tea and sit down, after getting a copy of a sort of news faxed to the station every day. Another antarctic day has just started.

Tuesday, January 14, 2003

... and Monday is Monday

We continue today with the removal of the ACBAR from the Viper telescope. Now, is time to remove the actual thing, a big barrell with 2 cubes containing fragile and delicate electronics.

The shape of the Viper telescope is a bit complex and difficult to describe as well. Forget what you remember about astronomical telescope. Imagine a big cut cone upside down on the top of a tower. This is the radiation shield, aimed to protect the detector from the sunlight and from the radiation coming from the relatively cold ground. The top of the shield is about 15 meter over the ground.

Inside, there is the proper 2.1 m telescope. At South pole you don't need, neither you wish, to build a dome, as there are no strong winds, and no rain that could damage the optics. Moreover, you want to keep the telescope as cold as possible, as warm things emits just the radiation that is detected by the telescope itself.

Are you looking for a big, fatty glass? Again, nothing like that. The primary mirror is just a large concave aluminum sheet, but with a peculiar shape, as you don't want anything in the path optical path. The mirror is surrounded buy a large guard, used, again, to avoid radiation coming from the ground. Radiation, from the far-infrared till the radio wavelengths has a very large wavelength, and, in turn, the very bad habit to behave like sound. You can hide behind a tree, but you can still hear that terrible country music piece your neighbours are playing, because sound doesn't go straight forward like light. This is why your hears are on each side of your face and not just on your front. And that is good, let me say, because otherwise you would look pretty ugly and everyone would laugh about you.

To complete this unsuccessfully and useless description of the telescope, I have to say that the detector is not under the telescope, but almost on his top, hanging over a sort of balcony apparently in front of the primary mirror, behind some other fancy aluminum mirrors used to direct the radiation on his optic in the desired mode. To reach it you have to climb up to the whole structure.

Dismounting of the detector is performed in panic mode, leaning your body from a sort of gangplank used to keep closer to it. After unlocking the detector from the mounting after acrobatic operation at 15 meters from the ground level, the 3 of us, Bill, Mike and me, get the instrument away, to discover that it doesn't fit into the shield hatch and we have to dismount the electronic. There is also a moment of real panic, when a panel of wood under my feet slide away and me and the big barrell, probably 100 Kg heavy, starts to move out of the gangplank. Bill, on the other side of the detector, after screaming some words that fit very well with what I said, except they originated on an Island much more Northern that Italy, cling to it, while Mike itself attach his amazingly large hands to the cover and help me to recover a stable position. Whoa! Pretty scaring, let me say.

After some acrobactics again, or, better, aerobatics, we have to dismount all the electronics, cable, that would be complex at the Hawaii, but is a torture when you consider that any screw means the use bare hands touching the metal, that we can't leave the detector in this dangerous positionl, and that if you start to complain because you are feeling a pain on your hands like if a rascal is hammering them for the cold, you will be since now on the shy violet of the party.

Anyway, at the end, we have the instrument down on the roof. After lowering it to the balcony in front of the door of the lab with the crane, we move it inside.

And so, that's my diary for today.

Monday, January 13, 2003

Sunday is Sunday.

Sunday is Sunday, also at the South Pole. You feel a bit lazy and clumsy, because you know that is Sunday but... you don't know exactly why. Just a few people go out of the station, and the usual movement of trucks, people, cranes and carnes is at the moment suspended.

So, the station is almost silent and, walking from the Dome to the Observatory, a walk on the ice about half a mile long, you can stop in the middle of the skyway, watch the perspective of flags surrounding it converge on each opposite side just at the horizon, and stop for a minute or so in the cold. You will hear just the wind blowing around of the hood and nothing else. Some hundreds meter away, the reassuring view of the vapour coming out from the chimneys of the new power generator, and the gentle and bright summit of the dome, filled with a lazy humanity watching movies, sleeping, reading books and chatting each other. It's a fashinating view. I enjoy repeating each time this sort of Sunday ceremony.

You restart moving toward the Observatory, in a fairy world where shadows disappears, because the clouds form a diffused glare joining with the snow at an undetectable horizon, but the noise of the snow crushed by your feet will cover again that magic wind blowing around you. You open the door of the building, looking like one of those heavy door enclosing the goods in the butcheries, cross the workshop, and reach the telescope control room.

Today we started to remove the detector that is currently on the focus of the telescope, and that will be substitute with another ones, called SPARO, till July. At present, there is an amazing instrument, ACBAR (Arcminute Cosmology Bolometer Array Receiver), suited for the measurements of that image of the firsts moment of life of the universe that is usually addressed as the Cosmic Microwave Background. Unlike other experiments, like Boomerang, this instrument is dedicated to the studies of the little features of that map of temperature of the ancient sky, not the larger ones. The detectors are cooled at about 250 mK by a smart series of cooler and cryogenic liquid baths, Into the dewar, a bottle designed to keep very cold liuids, is installed an array of very sensitive detector, called bolometer, able to react to the minimal change of the temperature of the sky. A fragile and noise-sensitive electronics drive the signal outside to the data acquisition.

Removing ACBAR means first climb up into the structure of the telescope, between the main dish and the secondary. Unlike with optical telescope, doesn't matter if you touch the main mirror, that is a large, curve plate of Aluminum, ecause the radiation, at this wavelength, is unaware of little scratches. Actually, one of my duties will be, during the winter, to clean up the mirror using a broome every 6 hours or so (not good for my sleeping cycle).

Bill and me take a measurement of the actual configuration, that will be used in mid winter, when, in pretty harsh weather condition, I will have to put back the instrument, to realign the instrument. Bill and me take plenty of pictures of also the most futile details, to let me able to rebuild the present optical alignment. After that, we squeeze out of the telescope through a thin hatch on the lower side, to dismount a calibrator, contained on a box under the telescope, that is used to measure the readiness of the bolometers in reacting to the change of temperature in the sky. All the operation takes a full afternoon outdoor. Time by time we have to remove our gloves to take some measurements, or to untight some little screws. And time by time we have to get back to recover from the pain that the cold, specially when touching metal, hit you has a bit of a venomos snake. The instrument is incredibly stiff and support the two of us without any complaints.

The Sunday passes with the two of us, Mike, and Martin, two other staff, outdoor. At 4 am in the night I walk back to the station, as usual in Antarctica, with no signs of tireness, and stop again to watch at the silent, at the smoke coming out of the station, but this vision of serenity is disrupted already by some of the workers working around the station. It is the "night shift", that starts on Monday night. Clinged out of the metal structure, a girl tighten some nuts. A crane move in the neighbours a stroke of snow ahead.

It's time to shelter into the Hypertat and fell asleep.




Sunday, January 12, 2003

Off topic. Maybe not.

Before leaving Sydney my wife given me a CD of awesome Puccini opera's arias.

It has been a great gift as you have to know that when Italians move away from their country something pretty strange happens in some part of their brain: they starts to raise a strong, crazy, endless passion about the Opera, and in particular about the most touching arias. Of course, there is people that was born with such a madness, but, talking to other Italians that moved overseas, I discovered that is a pretty common thing to happen. And, having spent 3 years in Sydney, the city with that amazing piece of contemporary architecture that is the Sydney Opera House, I pretty often enjoied what was in the manifest, "Cavalleria Rusticana", "Boheme", "Turandot", etc...

So, a few days ago I removed the cellophane envelope from that CD and started to enjoy it on my brand new laptop (thanks Giles!). Pretty soon, taking advantage of the nice hi-fi stereo amplifier available on the Viper control room, and of the slightly different tastes in getting lunch, I moved the arias to the players, and enjoied several times those amazing, astouding (what else in English after those adjectives?) that makes me, well, cry, time by time. But don't tell it to the Psycho, please.

Relaxed on the chair, I listened once, two, three, four time to the celebrated arias, not very often on air at such a latitude, I guess. And, well, suddenly I started to think a, we say, a theory about Puccini music, the kind of theories that could easily transform me from an Antarctic Astronomer to a, well, a music theoretician, or something like that...

In fact, I started to listen to the arias like if they were just talking about me and my next 10 months.

Ok, let's start with some practical examples. Most of you of course started to think that, yes, actually, "Ma che gelida manina, se la lasci riscaldari" [What a frozen little hand, let me warm it for you, from La Boheme] could be a nice way to approach girls at the South Pole but, as just my wife is a greedy reader of my diaries - that I hope - I'll have to forget that and go ahead. Let m talk about the ultrarenowned "Nessun Dorma!" The Princep actually sings at the beginning that "Nessun dorma!... Nessun dorma!... Tu pure, o Principessa, nella tua fredda stanza guardi le stelle che tremano d'amore e di speranza!" [No one sleeps!... No one sleeps!... Nor do you, o princess in your cold room. Look the stars that tremble with love and hope! from Turandot]. Pretty apt for an astronomer accomodated in a cold cubicle at the South Pole, isn't it? Ok, except that the Princess is a bit far away. But, let's proceed further: isn't it true that the aria ends up with the famous passage, able to let any (true) Italian start to cry like a kid in front of a dish plenty of boiled spinach: "Dilegua, o notte! tramontate, stelle! Tramontate, stelle! All'alba vincerò! Vincerò! Vincerò!", [Disperse, o night! Set, you stars! Set, you stars! With the dawn I will win! I'll win! I'll win!].

Doesn't look as the hymn to the intrepid Antarctic Astronomer stuck in a Station trepidly waiting for the end of the endless Antarctic Night? Well, and the Princeps for sure would have much more probabilities of success if would be wintering at South Pole, with six months of time available. And don't forget that La Boheme has been composed only 3 years in advance of the first wintering party in Antarctica...

Unfortunately, dear reader, it is time to get back to work. "Or lasciami al lavoro", [Let's get back to my job, from Tosca] it's time to start some hours of measurements...

Saturday, January 11, 2003

A very cold place

Bill worked all night and at the end found out that one component in one control board was partially faulty. This component was giving a really erratic output only in "some", specific situations, like when a person with a short bear and looking pretty stupid was at the telescope consolle.

We changed it in the morning and started a long series of test during the day. I'm getting familiarity with the telescope and today I did my first "recycling". Detectors currently used in Viper (there are two of them, called acbar and sparo) are operating at 0.24 Kelvin degree, that means only 1/4 of Celsius degree over the absolute zero, that is the minimal temperature you can reach. The average ambient temperature at South Pole is something like 1000 times higher. To reach and keep this temperature you need to use liquid Helium, that is boiling at 4 Kelvin, and than start a particular procedure that get to a much lower temperature.

Well, the problem is that all the Helium boil out after some time, so that you have to refill the detector every 2 days, and that the procedure used to get till 0.24 Kelvin has to be repeated every few days. In previous experiment I've been involved in, this didn't happen. With this detectors it is, altough complex, fully automated, that is pretty amazing.

But at South Pole this is the only way to go. Nobody could do such a procedure outdoor for an year. Anyway, you still have to refill the dewar with liquid Helium and Nitrogen any two days, for an year, no exception.

The problem is that this operation must be done in a pretty critical conditions and lasts about 40 minutes. In a lab is just a joke. Outdoor, on the top of the viper telescope in summer, when temperature are something like -25 C, is still ok, but you can imagine what happens when you are in the darkness, with temperature that can reach -87 C and a windchill (the temperature you actually experience, considering the effect of the wind) of something like -120 C. And you can't just say "I'll do it tomorrow", because this would mean the detector heating, that would mean a week of furious adjustment and work around it.

Also if the perspective is pretty scaring, I know that persons like me and you did the job, and so... Doesn't remain to me than wait and see. Gosh!

Friday, January 10, 2003

when things move quickly

Today we came here after lunch to substitude one of the three 2 Kw amplifier that drive the 3 azimuth motor of the telescope, allowing it to track sky sources. Everything was going smooth and after some time we decided to power up the system. I have been asked to type the right sequence of command while Bill was close to an emergency button that shut down the power in case of failure. I did it carefully while Bill was looking at what I did over my shoulder.

The telescope is not visible from the control room, but there is a camera mounted to show is current position. Bill adviced me to look at the camera while giving the last command, that actually enable the movement, and so I did.

Everything started smooth and Bill was starting to say something when, with the tail of my eye I've spotted the telescope, a structure about 4 meter tall and large, gainining suddenly speed and rotate, in a second, at something like 1 root every 2 seconds! I immediately try to say something, but in this situation, when you are not expected to speak in your native language, the only thing come out from your body is something like a loud scream in an unknown idiom. Bil, even before looking at the monitor, immediately pushed the big fatty red mushroom button and we observed the telescope to loose slightly speed while dangerously approaching the hard limit (the telescope can't do more than 1 round, and there are hard limits to prevent damages to the cables).

We remained for a few seconds in a complete silent looking at the monitor. Then we run to see what happened. Fortunately, nothing goes damaged and the telescope just hit gently the limit, that is pretty soft.

So, we spent all the day trying to understand what's happened (and we are still here doing it). It has been a really depressing experience because this happened just twice since 1999, and the second time just when I was for the first time controlling the instrument. There is something in the electronic that did it, and the unluckiness was that a protection system, installed to prevent just something like that, was temporary shut down at the time of the test.

Anyway, there has been no damage, that's the important thing, and we have just to understand what can went wrong once in an year, that is pretty hard because such a problem can be hardly simulated and debugged.

For the rest, the season is great here at the South Pole. Blue sky, no wind, all those thing that make easy to work outdoor...

Thursday, January 09, 2003

Herculeus efforts

The good poing of staying in the Hypertat (see some of my previous entries to know what I'm talking about0 is that, at least, there is a window. The first thing I do in the morning is to remove the heavy tissue cover that make the room completely embedded in the darkness during sleeping hours. What surprised me is that nobody else has this habit. When I walk down the corridor I find it at any time in an almost complete darkness, except for some electric, yellow and sad electrical bulbs light strips coming out from some of the cubicles doors. Also the other corridors (the hypertat are 4, called Fred, Barney, Wilma and Betty with evident reference to their primitive aspect) looks in the same darkness. I spoken to the other Paolo (yes, there is another italian in the station, and he is still called Paolo), and he said that he have the same habit as me. And noone else

I often try to imagine the winter, when I would be able to look at the star from my bed. But actually I will move soon from the hypertat to my winter accomodation in the new station. Yes, it looks like most of us will be sleeping in the new station, that is pretty interesting. I have not been there, but people say that the rooms are very comfortable.

During the breakfast I met an old knowledge of the AASTO program run by UNSW in South Pole. A nice fellow called Evan, that participated to the first phase of the AASTO installation. Evan is now involved in the development of a pretty unusual instrument: a 7.5 km long antenna that will transmit an electromagnetic signal at about 21 KHz able to study the property of the ionosphere. Such incredibly low frequency is the reason for such a long antenna. It has been already installed, on sticks about 1 mt over the snow level, and he is now installing the transmitter, starting from the same Dark Sector well I will spend the whole winter.

Evan spent the past years working around the AGOs, a sort of fiberglass shelter around which the AASTO has been designed and built. AGOs are spread out around Antarctica, and were planned to acquired a sort of meteorological data allover the winter. However, the almost complete unreliability of their propane-based power supply, the same used by the AASTO in the past, suggested to remove most of them or to change the power supply system to a new one powered by solar panel in summer and wind generators in winter, in the next few years.

Evan travelled the Antarctic Plateau for years. I asked him lots of questions about the organization that allowed the mantainance of the AGOS. For example, I always wondered if LC-130 can land everywhere in the continent, even on unprepared skyway. He said yes, and told me some pretty scaring stories about really rough landing. The procedure was to get to some place and start landing, but just a little bit. What does it mean? Well, the aircraft, a pretty heavy and large cargo on skys, was actually getting on the snow, and pushed just a little bit on the rear skies. After this touch and go, the pilot was flying again over the site, looking for any visible sign of open crevasses and dangerous surfaces. After that, repeated the operation a few meter on the side, and than landed in the middle between the two traces, if conditions suggested to do that. Thinking to the mass of the aircraft, and to the visibility from the cockpit, I couldn't even think how people could also attempt to do it once, without at least destroying the landing gear system.

The problem was that the ability of the pilot was to really push hard on the sastrugi, to make any possible danger visible. Meanwhile, the passengers inside were subject to any kind of vibration, with baggage flying everywhere. Once he receved on his legs an oxygen bottle fall from the wall.

Even more scaring was the JATO (Jet Assisted Take Off). Due to the roughness of the snow surface and of the altitude, the aircraft was sometime unable to reach the take-off speed, and so they used to attach something like 8 bottles containing some high energy propeller, close to the tail of the jet. Sometime the bottles was cracked, so that all the propellant was fired up in a while, the bottle broken their support and started to overcome the aircraft, usually crossing the propellers and destroying the blades with the kind of consequences you can easily imagine. Actually, there is a story about one blade that entered into the cockpit of the aircraft from one side, and get out on the other side (probably true), after cutting in half the zoom of the camera of a reporter that was not minimally injuried. I would like to say this is a possible candidate for a book around Antarctic Legends, also if several people tell the same story, with some differences.

The rest of the day passed getting familiarity with the VIPER telescope. I learnt essentially the basic commands, and get an overall introduction to all the subsystem. Really nothing in comparison of the Herculeus efforts made by my collegues at Dome C in the same moment. They are really pushing hard and get all my solidariety. I have to last longer, that's right, but I know the conditions in which they are operating and they got all my compliments for the great job done (also if they will not read what I'm writing about till they will find their way back out of the continent at the end of January).

Wednesday, January 08, 2003

CMB and S-Z

I guess there is a sort of "memory" in our body, and we keep apt to the altitude much longer than we would bid.

So, I wake up late in the morning with the program to just study documentation about the instrumentation I will work about. And so I did, spending all day in the station, also because a power shortage was planned and so all the instrumentation was switched off to avoid any chance of getting damaged.

At a first glance, the system I will take care of this winter looks really impressive. I will send some pictures soon or later. It is a really an astouding assembly of electronics, cryogenics, mechanics and optics. In particular, the optics made me excited like a kid. The aim of the telescope is to measure the so called Cosmic Microwave Backround anisotropy at a scale at which only a few experiments in the wordl works, one of them at the South Pole itself, DASI. One other thing is the socalled S-Z effect, that for sure my readers will know very well (actually, I am not in outreach-mode today).

At lunch, while reading that Saddam is really a bad guy from the news report supplied everyday by the station (no more than a Letter size piece of paper), as every day, I started chatting with two guys involved in the ITASE, the International Transantarctic Scientific Expedition. Several countries, in the past, started to think to do some ice core drilling and atmospheric science all over the continent, to understand more about the weather condition in the past. You get a core of ice, whatever deep, and you can, from the amount of aerosol (or dust) contained in the ice, understand the meteorological conditions 30 or 40 thousands here ago. Not enough to understand if on the 3rd of January 35,276 b.c. the Cro-Magnons get out of the cave with their heavy stone made umbrella, but enough to know if the average temperature was higher or lower, or if the snow accumulation was different, or how much vulcanic activity was typical at that time.

And so, several countries decided to collaborate and divided the continent in sectors, assigning the crossing of each sector to one of the country involved in the project. As a result, every year there are a few trucks traversing the continent in several directions. This is a really hard job. It takes months to find the way to cross the continent, getting rid of crevasses, fix all the mechanical problems, traverse region in which the wind is continouosly blowing and the temperature drop down a lot. The two guys I met were having the right phisique du role for the job and looks like if they come out from a cheap antarctic-heroes based movie. I really enjoy to hear from them the amazing stories of their traverse from Byrd Station to the South Pole and back to McMurdo.

What else? Well, today I have been informed I passed the psycho test and I'm now fully qualified for the winter over at South Pole. I'm the first to be surprised...

Monday, January 06, 2003

3, 2, 1 ready, go!

I left McMurdo today, abandoning for the last time another bunch of things, e.g. rocks, mountains (both visible altough pretty away from the station) and the sea, or the knowledge that there was sea water under my feet while I was waiting for the aircraft at Williams Field, the airport on the Ice Shelf.

We wait, wait, and wait. Than we taken off, but as I was deeply concentrating in trying to contain a strong wish to find a toilet, the pilot aborted the take off while almost airborne and got back to the airfield.

Actually, he said it was a technical problem, but the result is the same. Our baggages were moved to another LC-130 with a new crew, and we were moved there as well as about two hours later. Meanwhile, I spent most of the time trying to call back home unsuccessfully. A voice with an american accent was telling on the phone that my home number doesn't exist. What??? Maybe my wife already divorced from me.

Anyway, we gained again our place in the aircraft, after a reassuring visit to the toilet, that made me feel better. While taxiing, I spotted the Boomerang gondola moved out of the Pig Barn onboard of a tall crane. They launched later in the day.

I will consider my winter over started at 12:15 pm today 6th January 0. That's the time I walk out of the aircraft. This could not be very important for you, but let me say it is for me.

After several meeting a lunch and a talk to all the people I know here, in the afternoon I taken a visit to the Viper telescope, the place where I will spent most of the next 10 months, buried under papers, electronics, cryogenics, and mechanical parts. It is a little room in the MAPO building, the Astrophysics Observatory about 1 km away from the station. You enter the building, suspended by a large frame sinking in the snow, you cross a wonderful mech workshop filled with any kind of tool and spare, and after crossing a nother corridor you find my room. I wrote it just in case you should visit me in the near futur.

The room is surrounded by electronic racks and computer. I spoken with Bill, a scientist well known for talking at warp speed, and being introduced to the telescope, a gorgeous piece of technology rated to understand the best kept secrets of the universe. The Viper telescope looks complex, but by now I would say that is well designed and maintained. I hope I will not change my opinion. And that it has been well updated during the last summer, that will make my job easier during the winter. It is built around a 2m large aluminum mirror, built on the top of a tower, and protected by a sunshield cone-shaped even taller. You can lean down from the upper edge of the shield, the view is fantastic and look at the motor, the secondary, the tertiary mirror, and to the chopper, a mirror tilting its position at about 3 Hz, or to the dewar containing the detectors, hanging over the whole structure.

It is pretty different from what people imagine when thinking to a telescope. I’ll send you a picture as soon as I will get a digital camera to be used (the one I used earlier is currently at Dome C with the Storey’s team). And will have plenty of time to describe any minimal detail and get any of you, wherever you are in the world, fully bored.

By now, as usual, I feel my mood getting better any hour more. I’m not feeling very any high altitude sickness, probably a remember from my last trip. Tomorrow I’ll get, anyway, a day off, to avoid pushing too much ahead. I left Sydney a bit sad, thinking to all these time to be spent away from my partner and from my son, and to all the changes in my life that this winter will require. But Antarctica it’s really a great place, and is helping me to recover pretty quickly.

Paolo

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