Ice Stories: Dispatches From Polar Scientists » South Pole Telescope http://icestories.exploratorium.edu/dispatches Mon, 15 Nov 2010 20:40:36 +0000 http://wordpress.org/?v=2.9.2 en hourly 1 Sunny Days Are Here http://icestories.exploratorium.edu/dispatches/sunny-days-are-here/ http://icestories.exploratorium.edu/dispatches/sunny-days-are-here/#comments Fri, 01 Oct 2010 18:06:33 +0000 Nick Morgan http://icestories.exploratorium.edu/dispatches/?p=2373 SOUTH POLE, ANTARCTICA– Well to tell the truth, there hasn’t been too much to write about lately until now (hence the reason I have been absent in writing lately). But now we have the sun well above the horizon and it’s great to see again. Not only has it made my walk to ARO (Atmospheric Research Observatory) easier, being outside in the sun sparks a bit of energy and helps motivate to get some work done as we get ready to turn over to next year’s crew.


Notice the bit of sunlight on the side of my face!

The main station and sunrise. This photo was actually taken a day before “official” sunrise. In actuality, the sun takes a several days to rise.

On station, we have begun the large list of tasks posted by our station manager which mostly involve shoveling out buildings that have been dormant for the winter, and performing deep cleans of bathrooms, hallways, and work areas. I’ve decided that I have spent enough time inside so I volunteered for a few shoveling tasks namely the cargo office, cargo DNF (the building that houses cargo waiting to be sent out or received that can’t be frozen), and a summer camp Jamesway tent. The FEMC (Facilities Engineering Maintenance and Construction) crew is probably the busiest group with the station opening work as they have to get fuel to all the buildings and start heating them up so they are ready when the summer folks arrive. Our heavy equipment operators are busy as well removing snow and beginning to smooth out the skiway for the first flights. They have had a little bit of trouble due to the cold temperatures because they cannot operate the bulldozers under certain temps.


The BIF (Balloon Inflation Facility) is just below the Sun. To half cylinder shaped buildings to the left are the Jamesways that are being dug out and warmed up for the summer crew.

At ARO, I’m just finishing up inventory to figure out what needs to be shipped down during the summer. It is mostly unchanged from last year because we haven’t had many problems with the instruments this year so there will probably just be a few items to alert people back at ESRL in Boulder, Colorado about. We are also at our intensive ozonesonde launching period where we are launching every 2-3 days as opposed to our normal one per week. It’s been rather unexciting in the depletion department this year. It seems that the polar vortex may not be all that well defined as some years with very low ozone levels. A description of the process of the annual ozone layer destruction over Antarctica can be read in my previous post, “The Ozone Hole: It’s Still There!” Once the sun is a little higher in the sky, we will be able to resume daily measurements with the Dobson Spectrophotometer (measures total column ozone through the atmosphere).

The solar instruments have also been placed back on the roof and are collecting data again. Initially they were having trouble with the -90F temperatures, but we have seemed to iron out the problems and they are now tracking the sun well. For an overview of the solar instruments, see the previous post, “As Sunset Approaches, Let’s Talk Solar Radiation”.


The roof of ARO and various solar instruments.

The next thing that is on tap for myself is organizing all of the flask samples that have been taken over the winter and getting them ready to ship out in the summer. Mostly that just involves writing up the paperwork so it’s ready to go for my replacement (yay paperwork!). Oh, and packing. The thing I look forward to least is also on the agenda. I will need to find boxes to ship home all the things that have kept me entertained here such as my Playstation 3 and movies. As well as excess clothing that I don’t want to travel with.

As I mentioned in “The Ozone Hole: It’s Still There!”, I will be posting an ozonesonde launch with the plastic balloons that we use. Don’t worry, I haven’t forgot! I have it videotaped and will get it posted soon!

Here are some more nice pictures during the last month or so:


The Moon and Venus. The were the last two visible objects in the sky as the sun was closer to coming above the horizon.

ARO from halfway between the station and ARO

The Moon over the Clean Air Sector, directly opposite of the rising Sun.

Nice reflection off the corner of ARO

The Moon about to set out over SPT (South Pole Telescope)
]]>
http://icestories.exploratorium.edu/dispatches/sunny-days-are-here/feed/ 3
South Pole Nights http://icestories.exploratorium.edu/dispatches/south-pole-nights/ http://icestories.exploratorium.edu/dispatches/south-pole-nights/#comments Wed, 19 May 2010 18:04:34 +0000 Nick Morgan http://icestories.exploratorium.edu/dispatches/?p=2316 SOUTH POLE, ANTARCTICA– Here are some photos of the night skies at the South Pole.


South Pole Telescope (SPT) with a half moon

Early auroras over the Atmospheric Research Observatory (ARO)

Full moon rising over the Clean Air Sector

Dusk at ARO

The drift creeping up to the station

Managing my way around the snow drifts at ARO’s entrance

Starry skies with the LIDAR in view at ARO (similar to a radar but it’s a laser)

A view of the station from ARO

ARO and the meteorological tower with vivid aurora
]]>
http://icestories.exploratorium.edu/dispatches/south-pole-nights/feed/ 6
Astronomy in Antarctica http://icestories.exploratorium.edu/dispatches/big-ideas/astronomy-in-antarctica/ http://icestories.exploratorium.edu/dispatches/big-ideas/astronomy-in-antarctica/#comments Thu, 09 Oct 2008 19:55:17 +0000 Exploratorium http://icestories.exploratorium.edu/dispatches/?page_id=750
Aurora australis lights up the winter sky at the South Pole Station, Antarctica.

An Iridium flare flashes above the South Pole Telescope. (These flares occur when the sun reflects off of the Iridium satellites used for remote communication in Antarctica.)

NASA’s Ultra Long Duration Balloon. Once released, these balloons expand to the size of a stadium.

These light sensors (Digital Optical Modules, or DOMs) are placed deep within the ice in order to detect the blue light emitted when neutrino particles collide with atoms in the ice.

Ask an astronomer to describe the perfect place to put a telescope, and here’s what she’ll tell you: Make it cold, make it dark, make it high-altitude, and make it remote. In short, make it Antarctica.

All light-based astronomy is vulnerable to interference from the atmosphere, the same jittery effect that makes stars twinkle. Much like trying to see the bottom of a swimming pool, observing space through the moving air masses in our atmosphere causes images to wiggle and warp.

The very attributes that make Antarctica inhospitable to life make it ideal for astronomy. The high altitude means there’s less atmosphere to look through. The cold, dry air makes for minimal water vapor and less atmospheric emission of infrared light, both of which interfere with observations. Best of all, 24-hour darkness in winter means no daily temperature oscillations, reducing air currents.

The South Pole Telescope, located at the Amundsen-Scott Station near the South Pole, takes advantage of these clear skies to search for evidence of dark energy amid galaxy clusters. Dark energy is theorized to be a form of energy that is pushing everything in the universe apart.

To further reduce atmospheric interference, some astronomers use balloons to bring their instruments 35,000 feet into the air. Inexpensive compared to satellite-based astronomy, balloon-borne astronomy is ideally suited to Antarctica, where circumpolar winds high in the stratosphere carry balloons steadily and predictably around the pole.

One of the biggest astronomical efforts in Antarctica is actually taking place under the ice. IceCube is an array of ultra-sensitive light detectors buried a mile deep into the Antarctic ice sheet. These detectors can spot the passage of high-energy neutrinos, particles created by the most violent events in the universe, allowing astronomers to see impossibly distant cosmic events by detecting the neutrinos they create.

ICE-T on Dome C
An international team of astronomers have their sites set on another location in Antarctica—a formidably remote location known as Dome C—for construction of a new telescope. High on the Antarctic plateau, Dome C boasts atmospheric conditions that are even calmer—and thereby clearer—than those at the South Pole. “A telescope there would perform as well as a much larger one anywhere else on Earth,” says Will Saunders, astronomer at the Anglo-Australian Observatory. “It’s nearly as good as being in space.” The telescope in the works for Dome C, called ICE-T, will search for exoplanets, earth-like planets in other solar systems.

]]>
http://icestories.exploratorium.edu/dispatches/big-ideas/astronomy-in-antarctica/feed/ 0
Leaving on the Very Last Plane http://icestories.exploratorium.edu/dispatches/leaving-on-the-very-last-plane/ http://icestories.exploratorium.edu/dispatches/leaving-on-the-very-last-plane/#comments Wed, 13 Feb 2008 06:06:10 +0000 Kathryn Schaffer Miknaitis http://icestories.exploratorium.edu/dispatches-new/?p=67 The station is closing today. It is one day earlier than we were expecting, which means we have had a last-minute scramble to finish all of our tasks at the telescope. Bad weather is approaching the station, forcing an early close for the season.

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.

kathrynspt.JPG
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.

goodbye-for-9-months1.jpg
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.

kathryn_on_dish.jpg
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!

victoriansunset-72.jpg
During the coming austral winter months, the rising sun will sink closer and closer to the horizon until it disappears entirely.
]]>
http://icestories.exploratorium.edu/dispatches/leaving-on-the-very-last-plane/feed/ 0
Climactic Success http://icestories.exploratorium.edu/dispatches/climactic-success/ http://icestories.exploratorium.edu/dispatches/climactic-success/#comments Thu, 07 Feb 2008 14:06:59 +0000 Kathryn Schaffer Miknaitis http://icestories.exploratorium.edu/dispatches-new/?p=70 Everyone here is breathing a huge sigh of relief. Last night was the first night that our new set of detectors were cold enough to be operated. Unlike the last few test runs, for this run we had mounted the receiver up in the telescope where it normally lives, in preparation for doing real observing. As soon as the detectors were tuned, we pointed the telescope at an object in the sky called RCW38, which is a bright source of radiation at the frequencies we observe.

rec1.jpgOne 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!

rebuilt_receiver.JPG
The complete rebuilt receiver.
]]>
http://icestories.exploratorium.edu/dispatches/climactic-success/feed/ 0
The Clock is Ticking http://icestories.exploratorium.edu/dispatches/the-clock-is-ticking/ http://icestories.exploratorium.edu/dispatches/the-clock-is-ticking/#comments Tue, 05 Feb 2008 14:07:13 +0000 Kathryn Schaffer Miknaitis http://icestories.exploratorium.edu/dispatches-new/?p=71 I looked up at the weather screen today and saw that the temperature had dropped to -38 F (which is actually almost exactly equal to -38 degrees C). The windchill today is about -60F. The dropping temperatures signal that the end of the season is rapidly approaching. Soon, it will be too cold for planes to land here, and the station will be isolated for a period of 8 months. Most of the South Pole Telescope team is scheduled to leave on one of the last two flights out, expected to be on February 14 or thereabouts. As the end of the summer season approaches, personel on station are changing over as the summer staff leaves and the winter staff arrives. Rumors are flying about the station closing early, and about whether enough food and fuel have been delivered to sustain the station over the long winter. I think those rumors are as much a part of this season as the daily drops in temperature.

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.

rec2.jpg
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.

rec4.JPG
The “wedding cake”, aka rebuilt receiver.
]]>
http://icestories.exploratorium.edu/dispatches/the-clock-is-ticking/feed/ 0
Order & Progress http://icestories.exploratorium.edu/dispatches/order-progress/ http://icestories.exploratorium.edu/dispatches/order-progress/#comments Sun, 03 Feb 2008 14:07:42 +0000 Kathryn Schaffer Miknaitis http://icestories.exploratorium.edu/dispatches-new/?p=74 A few weeks ago, I posted pictures from a walking tour of the edges of the station. (To read that post, please click here.) Behind the station, construction materials, old scientific equipment, and curious miscellany have been collected over the years in rows out on the ice. With construction on the main station near completion, the major building project on station this season has been a new facility to provide indoor storage for many of the materials currently stored outside.

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.

spt_behind_the_station.JPGThe view from behind the station.
spt-building-757570.JPG
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.

dome_peeking-7442481.JPG
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.

]]>
http://icestories.exploratorium.edu/dispatches/order-progress/feed/ 0
SPT TV http://icestories.exploratorium.edu/dispatches/spt-tv/ http://icestories.exploratorium.edu/dispatches/spt-tv/#comments Sat, 19 Jan 2008 14:13:11 +0000 Kathryn Schaffer Miknaitis http://icestories.exploratorium.edu/dispatches-new/?p=82 Last week, I had the opportunity to drive the telescope around a lot. We’re not actively observing, but we are making many upgrades to the software that controls the telescope, and trying to debug little things that didn’t work as smoothly as we liked last season. The only time of day when I could do this was between the night and day shifts, for a couple of hours when nobody else needed access. All season we have been working on insulating the telescope and doing a better job of sealing the inside of the instrument (and the lab) from the elements. This work requires keeping the telescope stationary and often “docked,” meaning that it is parked above the control room so that we can get access to the cabin that normally holds the receiver. So I had to squeeze in between the day and night shifts of carpenters and SPT scientists who might need to work around the telescope.

kathryn_on_dish.jpg
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.

spttv-791970.JPG
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.

]]>
http://icestories.exploratorium.edu/dispatches/spt-tv/feed/ 0
Our New Sunroof http://icestories.exploratorium.edu/dispatches/our-new-sunroof/ http://icestories.exploratorium.edu/dispatches/our-new-sunroof/#comments Sat, 05 Jan 2008 14:21:41 +0000 Kathryn Schaffer Miknaitis http://icestories.exploratorium.edu/dispatches-new/?p=99 It’s been a busy couple of weeks out at the telescope. SPT postdoc Brad Benson and graduate students Martin Lueker and Joaquin Vieira installed a new set of detectors into the SPT “receiver,” which is essentially the camera for the telescope. A full array of detectors for our receiver consists of 1,000 individual pixels. Each pixel is an exquisitely sensitive device that registers tiny temperature changes when it absorbs electromagnetic radiation like that from the early universe. We record electrical signals that tell us essentially how much heat each detector has absorbed as we scan the telescope to point at different locations in the sky. For now, however, what we are interested in doing is testing the new detectors without installing them in the telescope itself, and just seeing how they work. These detectors are a major research project in themselves, and each batch incorporates new features as we learn more and more about their performance.

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.

sunroof-726115.JPG
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.

sunroof2-726185.JPG
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!

]]>
http://icestories.exploratorium.edu/dispatches/our-new-sunroof/feed/ 0
What Passes for Weather http://icestories.exploratorium.edu/dispatches/what-passes-for-weather/ http://icestories.exploratorium.edu/dispatches/what-passes-for-weather/#comments Mon, 24 Dec 2007 16:15:32 +0000 Kathryn Schaffer Miknaitis http://icestories.exploratorium.edu/dispatches-new/?p=106 We’re guaranteed to have a white Christmas (of sorts) here at the South Pole. But it won’t snow. It is normally too cold here for any form of precipitation. The snow on the ground here is different from the December snows back home. It squeaks when you step in it, and the particles in the air are not snowflakes but tiny, diamond-like fragments of solid ice swept up by the wind. We do get days when the wind whips enough ice into the air that you can see no more than ten feet in front of you. On these “white out” days, the array of flags peppering the landscape begins to make a lot of practical sense, marking the paths back to the station. The wind causes massive snow drifts, and after a large wind storm, the flags above the snow may be the only way to know where the carefully groomed roads once were.

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).

kathryn2.JPG
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.

kathryn1.JPG
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.
]]>
http://icestories.exploratorium.edu/dispatches/what-passes-for-weather/feed/ 0