I can’t believe I’ve been here for almost four months. I have worked harder during that time than I have just about any other time in my life. That is one thing about living in a station where people are working 24 hours a day – you can easily feel that you should be working at all hours, every waking moment. All meals are shared with collaborators, and even social times often drift into long discussions about the telescope. It is a recipe for incredible productivity, but after a few months of being so saturated in my work, I am also looking forward to taking a few days to enjoy other things in life. I will be headed home to Athens, Ohio for a few days to visit my family, reunite with my cats, and rediscover pleasures like bathtubs, fresh vegetables, and dark nights. I am looking forward to it.

Farewell for now, South Pole!

Like last season, I’ll be flying out on the very last plane. It will be an event. For eight months, all flights to and from the South Pole will be suspended. The fifty people staying here at the station will have an emotional moment, watching our plane take off. It has the feel of a celebration, closing the summer season and officially beginning the winter season. But at the same time the apprehension and the vague unease among the winterovers is almost palpable. In a few weeks the sun will sink low to the horizon, and then eventually the station will be plunged into total darkness and extreme cold for months. I would love to have the experience for a few days, but I don’t know if I could handle it for such a long time.

Last year’s winter-overs waving goodbye as the last plane for 8-9 months departed.

For me, the most emotional thing about leaving is the last glance to the telescope. Everything in my life has revolved around that instrument while I have been here. In the last moments, it almost acquires a personality in my perception. I imagine it watching us prepare to leave, tired from a long season of modifications and upgrades, and ready to begin scanning the microwave sky.

Bonding with the telescope.

Thanks to everyone for reading this blog through my stay here, and for all the comments and emails. This will be my last post for a while, possibly until the next time I make this long trip. Stay warm!

During the coming austral winter months, the rising sun will sink closer and closer to the horizon until it disappears entirely.

One layer of the new receiver. The small, single millimeter-wide circles at the top are our ultra-sensitive detectors.

We made a beautiful map of RCW38 and began learning about the properties of our new detector array, which looks fantastic. We still have a lot to learn before we leave, but last night was the big test, and possibly the most exciting moment of the whole season. We celebrated our success by sipping champagne out of paper cups while we looked at our very first data from the upgraded instrument. The enormous efforts that went into the upgrades this year look like they’re going to pay off!

The complete rebuilt receiver.

For SPT, this is a tense few weeks. We have just installed a brand new set of detectors in the receiver. These are much more sensitive than the ones that we used last season, but every new batch of detectors made at Berkeley is different, and it takes a lot of work to understand their features. We have a very short time to get the new receiver working, characterize the detectors, put everything in the telescope back together again, and get it all to work together. In the midst of this, we have two new members of the collaboration (Keith Vanderlinde and Dana Hrubes) who will be operating the instrument over the winter. They both need to be trained, and are understandably anxious about learning enough in such a short time to handle everything that could go wrong once the rest of us leave. I am not personally involved in much of the receiver work, but the tension permeates everything that we are currently doing.

This is a close-up picture of a set of detectors like those we just installed. Each little circular element is a few millimeters across, and is an ultra-sensitive radiation detector. The full array that makes up our focal plane consists of hundreds of these.

The detectors are fabricated on wedge-shaped wafers and then carefully installed in a ‘wedding cake’ assembly with optical feeds above each detector and a triangular filter above each wedge. The filters ensure that the radiation that reaches the detectors is the right frequency. The process of assembling and installing the focal plane is one of the most delicate tasks on this project. It’s taking place right now as I write this entry, and if everything goes well we’re on our way to a beautiful, sensitive new detector array for the second season of the SPT.

The “wedding cake”, aka rebuilt receiver.

Over the few months that I have spent here, I have had the opportunity to tour the construction site a few times, and recently I took some pictures of the building in a state of near-completion. Building at the South Pole poses significant and unusual challenges, among them the fact that any structure on this windswept plateau accumulates snow drifts sufficient to bury it in just a few years. The main station is designed on stilts, and the entire thing can be jacked up as the snow accumulates over time. Other facilities on station have to be dug out each season by bulldozers. The Dome, which was the previous South Pole Station, is slowly being buried. Its shape was designed to provide a strong shelter capable of withstanding the steady accumulation, but not indefinitely. The facilities surrounding the dome have been housed under arch structures, which are similarly designed to provide strong shelters for the buildings underneath.

The new materials and storage facility is replacing some of the arch structures and previous facilities that surrounded the old Dome. In the picture below you can see the power plant on the left, the heavy machine shop on the right, and in the center is the arch where construction has been taking place this year.

The view from behind the station.

Inside the arches.

Even for me, walking around inside these worksites feels strange – just last year, there were still buildings under these arches that I visited, including the last South Pole bar. In between the new building and the storage arch that sits behind it, you can see the Dome – almost thoroughly eclipsed by the construction activities. In the last picture below, the original welcome sign to the South Pole Station rests on the ice behind segments of arch meant for the new facility.

The end of an era.

Everything built here is constantly changed, adapted, and upgraded to cope with the unchanging harshness of the environment at the South Pole.

The massive telescope—with me on top for scale. (To read the dispatch on why I was on top of the telescope in the first place, click here.) The telescope is 75 feet (22.8 meters) tall, 33 feet (10 meters) across, and weighs 280 tons (254 metric tons.)

For a few days, I went out and undocked the telescope and moved it around a bit to do some motion tests with various changes to the software. Moving the telescope involves issuing commands by computer from inside the lab. There is something truly awesome (and very intimidating) about having an instrument of this size under your control. First of all, it can be downright terrifying. The thing moves at an improbably high speed. It is massive! You can’t imagine what it’s like to see a thing of that size move so fast, and so smoothly, until you have witnessed it. Operating something that large is just sort of scary. Especially when (as was the case last week) some of the software changes led at first to unpredictable behavior. One of the stranger things is that if you are moving the telescope from inside the control room (which is directly under it), you can’t see where the telescope is going. You can see the inside moving (the gears are awesome, and the entire roof rotates if you swing the thing around in azimuth), but it is nevertheless unnerving not being able to see where it points.

So, I was quite happy when Erik Leitch brought over a camera and a little TV monitor and installed them. It’s an old camera and an old TV previously used to keep an eye on the DASI telescope.

SPT TV!

It was a great improvement during the motion tests last week, if only to keep me from getting too jumpy! But there was something inherently funny about having an old black-and-white TV monitor in the midst of our otherwise high-tech and state-of-the-art laboratory.

The new station has been under construction for years, and for a newcomer like myself, it already feels like it’s been here forever. I went into the dome last year, but already by that time the main living quarters were dismantled and mostly it was being used to store office supplies and snack foods in big racks criss-crossing the well-packed snow floor inside. For many people here, though, that dome was once home. Sometimes for the better part of many years, for the really dedicated members of the U.S. Antarctic Program who have wintered over many times. The work to build the new, modernized station has been intense, and today’s formal dedication was the culmination of a massive, monumental effort. I could tell it was very sentimental for many members of the community.

For me, the official ceremonies do not have the personal significance that they do to people who have been involved in the South Pole Station for five years, a decade, or even two. But I am not without a good deal of awe for their accomplishments. Ironically, what made me most aware of the sheer scale of the project to keep a station going year-round at the South Pole, and most aware of the history and the people who have kept it going, was a recent tour of the grittier sides of station activites. Last week I went for a wander behind the station, looking in on all of the trade shops (carpenters, plumbers, electricians), the storage berms, and the out-of-the-way spots where old construction materials and decommissioned scientific equipment are stored, awaiting shipment back to the states.

New storage facilities are being built, as part of modernizing the station. But for years, elevated stretches of packed snow behind the station have been used to store construction materials, frozen food, and scraps of anything that might bear reuse in the future. This part of the station can feel like an endless sea of cardboard boxes, stacked pallets, and scrap metal.

Old scientific and communications materials are stored here, as well as anything else that breaks or becomes obsolete. It is all gradually on its way out, on return flights back to the U.S. But while it waits, exposed to the bare Antarctic elements, it conveys to the wandering observer a real sense of the history of this place and the unique mixture of basic life support services with technology and cutting-edge science that has always characterized daily life here.

Below are a few more pictures from my tour. A couple of these are of an old radome, an enclosure built to protect communications antennas. There are also stacks of giant empty spools, segments of arches used for storage facilities, and aisles of construction materials. All evidence of the massive, monumental scale of maintaining a research station here in all of its forms over the years.

An old randome– an enclosure built to protect communications antennas.

Inside randome.

Spoolhenge

Segments of arches used for storage facilities.

Because these new detectors are so sensitive, the radiation from any warm object in their field of view can overwhelm them–essentially they overheat. For the tests that we wanted to perform, we installed the receiver on the optics cryostat, which holds the 1-meter secondary mirror for the telescope, and usually lives up in the big boom below the dish. We needed a way to point the window in the optics cryostat out at the sky without mounting it back up into the telescope. So, what we’ve been doing is opening up the sliding roof above the control room and using a big metal plate to bounce light from the sky into the optics cryostat, and eventually to the detectors. The sky is the coldest thing around, and it’s also what the detectors are designed to see.

Our sunroof. The big white vessel is the cryostat that holds our secondary mirror at a low enough temperature (around ten degrees above absolute zero) that its own radiation doesn’t swamp our detectors. In this picture you can’t see the red receiver cryostat bolted to it on the other side–that’s what holds the detectors. The large silver box is the FTS, which I’ve described before. The big metal plate is what’s making sure that our detectors are mostly looking at the sky.

However, this has made for interesting working conditions in the lab. It’s nice to get the natural light in there, but with the ceiling open to the South Pole environment, it’s been freezing! For the last week I’ve been working in the control room at my laptop, controlling some of the tests and looking at data. I always have enough clothes on that I don’t feel cold, but I really notice how much harder it is to type. The fingers just don’t want to move quickly. At times, the wind was even blowing snow through the roof, and it was bizarre to have a bluster of ice flakes swirling around in the room.

We just finished two days of taking FTS measurements to characterize the response of the updated receiver to light of different frequencies. In the picture below you can see what it looked like from the other side of the setup.

The lenses and windows in the center of this picture are part of the setup used to direct just a little bit of light from the FTS instrument into the receiver, so that it’s not too much for the detectors to take. Mostly, the detectors are looking straight up into that sunny blue sky. We are working right under the telescope itself, and you can see the bottom of the telescope boom in the background. In this position, the telescope is on its back, with the dish staring straight up as well.

It’s been a busy but successful couple of weeks, and we’re about ready to close up the sunroof and move on to the next projects for the season. It’s never dull around here!

The second I saw it…

…I fell in love with it.

As it’s been explained to me, the tree started a few years back when the night shift iron workers built it out of scraps and discarded metal parts. Each year since, members of the iron crew have added their own ornaments and adornments, resulting in a monstrous sculptural creation with more personality and character than any other Christmas tree I have ever seen. The ornaments are made from nuts and bolts, broken tools, saw blades, gears, and any sort of scrap that can be dug out of the recycling bins in the shops around the station. Limbs of the tree fall off and it requires repairs and adjustments every season.

Working on night shift often means missing most of the main social events of the holiday season. But one perk was that tonight I was able to go outside and watch this year’s contributions to the ironworker tree.

Boss Erik Nichols looks on as iron crew member Kate Allen cuts her ornament.

After the piece fell to the ground it immediately began to melt itself into the ice.

Erik’s ornament was an enormous snowflake made of nuts.

Josh Miller attaches his own contributions.

I’ve been working so much and I’m so far away from the regular holiday traditions back home that I’ve barely been aware of the season. But watching the night shift iron crew decorating their spectacular and bizarre holiday tree put me in the Christmas spirit. I love the creativity here and I feel so fortunate to be able to experience a little of it.

Happy holidays to everyone back home!

Every few minutes, television screens in the galley display the current weather. This consists of the temperature, the wind chill, the wind speed and direction, and the physiological altitude (mainly a function of the air pressure).

Often there is no perceptible change in the weather for days on end, but everyone still keeps an eye on the screens in the galley that show up-to-the-minute stats. If it’s not just out of habit, it is often because the weather page is accompanied by personal photographs submitted by polies. Each weather page shows a new photograph. These are frequently funny pictures from recent parties, or beautiful shots of sundogs. But one very thoughtful person recently submitted a picture that he had of one of my cats, knowing how much I have been missing them. It appeared on the screens during midrats (night shift’s lunch) today, and it made my day.

Wind determines the “weather” here. Lately, it has been warm and the winds have been mild, but irregular. Last night while I was working, it seemed that every time I looked out the window the landscape had completely changed character. One moment it was blue and sunny, the next it was grey and the sky was threatening to consume the horizon and merge with the ice below. In the space of an hour the view through the science lab window changed colors and moods several times.

Earlier in my trip I took a picture of some sand-dusted footprints that remained in sculptural relief after a wind-storm at McMurdo. The same thing happens here at the pole when the winds have been very high. With each boot-step, the snow is compressed. The wind eats away the loose powder around and (sometimes even under) the footprints before they begin to crumble away themselves. I took this photograph after a day of high winds and cold temperatures. You can see the tracks from someone making the trip out to the telescope. Enough ice was in the air that day to create a sun-dog, a glowing ring around the sun that is one of the real treats of being here.

The surface of the reflector itself is made up of many individual aluminum panels that are set by hand (basically by adjusting about a thousand individual screws) so that the total surface has a shape that is perfect to within the thickness of a human hair. It is really an impressive thing! It does not necessarily look as perfect and beautiful to the human eye as it does to the microwaves it is designed to reflect, so you have to use your imagination a little when you look at the pictures. The reflector has lots of marks from stickers and tape that we have used for various iterations on measuring and adjusting the surface. Jeff’s measurements had reached a level of accuracy such that the largest of these stickers simply had to go. As the lightest member of the team, it made some sense for me to perform this slightly unnerving operation of crawling around the dish to peel them all off.

My precarious perch atop the reflector.

The task was actually a lot more difficult than I expected. I tried to dress somewhat lightly so that I wouldn’t be bogged down and could move around carefully and comfortably. But consequently, I was freezing cold. We got me up into the dish with the telescope resting on its back (I won’t describe how but again, use your imagination). I had to crawl around on two foam pads, carefully distributing my weight across as many panels as possible each time I moved. Inside, the surface of the mirror is actually quite steep and any kind of motion required a lot of care to avoid sliding, falling, or dropping gloves or tools into the center. As I moved around the dish I had to pry off each sticker and remove all of the adhesives and tape used to fix it in place. There was no way to do this effectively with gloves or my glasses, which fogged up uselessly, so it was surprisingly difficult for such a simple task. The whole operation took a couple of hours and I was really feeling the cold by the end of that. But it was definitely a unique experience I will never forget–how many people get to climb around inside a gigantic telescope, at the South Pole no less? I was also relieved to find out later that my telescope traverse did not alter the overall shape of the dish to within the accuracy of Jeff’s measurements. Phew!

Waving from the giant telescope.

Jeff took some pictures while he was standing outside, making sure that everything was going OK. That’s me waving. All that plywood you can see on the telescope boom was also part of Jeff’s project to measure the dish more accurately, and now that his instruments are all packed up we will put the normal roof back on.