Back on the sky!

As of February 6, the new and improved SPT receiver is installed in the telescope and looking into the heavens. The last 10 days or so until South Pole Station closes for the winter are being spent characterizing the new array, focusing the telescope, and (this one is really important) making sure our 2008 winterovers Keith and Dana are prepared to run this beast and deal with any situations that might arise. Once these tasks are completed, we will settle into a stable observing routine for the winter season.

As a teaser, here's an image made from one of our regular observations of a galactic HII source:

We're famous! Final Webcast of the season, the Press and RSS

We had our final Exploratorium webcast yesterday, January 18th. The show is archived on their website in case you missed it. In other exciting news, the Chicago Tribune recently ran a story on the SPT. It was amazing seeing familar faces and photos from the pole splashed across the front page! For those of you not residing in Chicago, the article can be found here. Finally, we added RSS to the blog (thanks to our readers for the suggestion).

Check us out today on NPR!

Talk of the Nation will be doing a piece on the South Pole Telescope this afternoon. Tune in and listen or check their website after 6 (EST) today for the piece.

Upcoming Live Webcast: Dec. 21 2007

Be sure to visit the Exploratorium's website for another live webcast from pole on Dec. 21, 2007 at 8 am CST.

Live SPT-Exploratorium Webcast Tomorrow! (Dec 7th)

Be sure to head on over to the Exploratorium's site tomorrow at 9:00 CST to join us for a live webcast with members of the SPT team at pole. This is a great opportunity to ask SPT scientists questions about their research.

The last few weeks at pole we have been busy characterizing our detectors (Kathryn talks about her work on this here), preparing our receiver for an upgrade and improving the surface of our primary mirror. On the primary mirror, we hope to achieve a surface smoothness of 20 microns (less than the thickness of a human hair), which is quite an accomplishment across a 10 meter dish! Back in the states, we have been busy fabricating and testing new pixels for the camera this season. Here is a (seasonably appropriate) photo of one of new bolometers magnified 500x under a scanning electron microscope (SEM). Click here or here for more information on our detectors. For more on the SEM check out these links (background, gallery).

It has been a while since we last posted but that doesn't mean we haven't been busy. We just finished observing for this season and it was a success! Since deployment lots of exciting things have taken place. The SPT winter-overs, Zak Staniszewski and Steve Padin, have been living at the South Pole running the telescope. Since the SPT detectors operate at very low temperatures, the winter-overs spent part of each day cooling the detectors and setting them. Then, when the telescope is ready to observe, they use a computer to command the telescope to point at the regions of the sky that the collaboration decided to observe this Austral Winter. Each day the data is sent back to the SPT collaboration via satellite and the analysis team sets to work processing the raw data. One of the main goals of the analysis at this stage is to understand how each element of the instrument is working. The telescope is a very complicated instrument and before we are ready to use this data for science, we want to be really sure we understand how everything is working, especially the hundreds of individual detectors making up the camera. The next step in the analysis is to write a complicated set of computer programs that take raw data and process it into maps of the sky. We will be working hard over the coming months to prepare these maps and study them. Besides the analysis, there is a flurry of activity as we work to create an updated receiver to install on the telescope during the coming Austral Summer. Already, the first few members of the collaboration are headed back down to the pole to begin this season's work on the telescope


Below are some great pictures of the telescope during the Austral Winter taken by Zak Staniszewski and Steve Padin.



The telescope after a storm.




The aurora, a phenomenon seen most commonly at the poles of the earth caused by the interaction of the solar winds and the particles in the earth's magnetosphere.




The moon shining brightly behind the telescope.



The sunrise after a long dark winter. Since the earth's axis of rotation is tilted with respect to the light coming from the sun it is always dark for part of the year at South Pole and always light the other part of the year. For this reason, the sunrise is a very special event.




The white snow and telescope looking beautiful as the rising sun reflects off them.

The Long Goodbye

Now that the busy polar summer season is over, things have gotten much quieter around here. Although there are just two SPT team members (Zak Staniszewski and Steve Padin) left at pole, there is still tons of work to do! Right now we are busy commissioning the telescope, and thus far everything is progressing well. Here is a shot of the SPT scanning during these early tests:

Be sure to go check out the newly revised SPT Multimedia page where we've uploaded lots of movies and photos from both the test build in the US and construction at pole this season.

Now that February is here, the temperatures at the South Pole Station have begun to drop again, and the station is preparing to close for the winter. Most of the people currently working at the station will fly out within the next couple of weeks, leaving only a core group of "winterovers" here who will stay through the extremely cold and dark months of the Antarctic winter.

The University of Chicago "reflector assembly team", consisting of Tom, Jeff, Joaquin and Ryan, has already left the ice. But many members of the SPT project are still here until the very end of the summer season to work on the receiver, the last few details of the telescope itself, and the software used to control the telescope and interpret the data that we take with it. At the moment, we are busy cooling down the receiver and the secondary optics in order to test how everything works when we put it all together. It's a very busy time, with people working around the clock.

Even though we all tend to be very focused on whatever tasks are currently at hand, everyone in the team finds themselves sometimes just staring at this beautiful telescope and admiring everything that has already been achieved this year. It really is a gorgeous instrument, and it's especially impressive to see how smoothly it moves. From the windows of the indoor laboratories where most of our work is taking place, we can see the last remaining crews who are working on the telescope outside in the cold. To assemble this enormous telescope has taken teams of iron workers, electricians, insulation workers, carpenters, and many other specialists here at the Station and back in the U.S. It's been incredible to be here and see how the whole South Pole Station is pushing for the success of this project.

Before the Chicago reflector assembly team left, we had a chance to take some pictures of them together with the iron workers and telescope specialists who played big roles in the construction of the telescope. Many of these individuals went through the process of test-building the telescope in Texas last summer, and here they are at the completion of the final instrument in one of the harshest places on earth. It's truly a great group of people and they've done an amazing job. All of the rest of us are in awe!

The Gang's All Here!


(Photo credit: John Kovac with Adrian's camera. Click here for a higher-res version.)

For a brief couple of weeks, we have assembled the entire SPT 2006-2007 South Pole Science team --- i.e., every scientist on the SPT project that's coming down this year. As you can see, we're quite a crew:

Lying down: Steve Padin

Kneeling (left to right): Tom Crawford, Kathryn Miknaitis, Tom Plagge, Matt Dobbs, Ryan Keisler

Standing, 1st row (left to right): Ken Aird, Zak Staniszewski, John Carlstrom, Joaquin Vieira, Martin Lueker, Erik Leitch, Jeff McMahon, Adrian Lee

Standing, back row (left to right): Clem Pryke, Steve Meyer, Brad Benson, Bill Holzapfel

Looming, background: The SPT

The Receiver Has Arrived.

The final (and possibly most complex) piece of the great puzzle that is the South Pole Telescope has arrived: The receiver. This is the end of the line for the light gathered by the telescope. Those ancient photons will end their existence being absorbed as heat onto the web of one of the ~1000 ultra-cold (1/2 degree above absolute zero) detectors, sensed as tiny temperature fluctuations by the tiny superconducting thermometer attached to the detector's web, and read out by the SQUID (superconducting quantum interference device) current meter / amplifier coupled to the detector. Computer records of these tiny temperature fluctuations will allow us to reconstruct the small-scale brightness pattern of the Cosmic Microwave Background (CMB) with unprecedented sensitivity, eventually enabling us (we hope) to measure the abundance of distant galaxy clusters through the distortion they imprint on the CMB and use this measurement to constrain properties of Dark Energy.

So we're pretty excited to have the receiver here. And already together and about to undergo some pre-installments tests. Amazing as it may sound (at least, it sounds amazing to me), the crew of newly arrived SPT scientists working on the receiver managed to unpack the receiver, open it down to its guts, install the detectors, close the receiver back up, and get it on the vacuum pump and cooling down within about 48 hours of its (and their) arrival.

(Speaking of which, we should note that we are now about a three times larger group of scientists than we were a few short days ago. Just arrived are: the receiver team of Bill Holzapfel, Adrian Lee, Brad Benson, Martin Lueker, and Tom Plagge (all from UC Berkeley) and Zak Staniszewski (from Case Western); Steve Meyer from Chicago (providing yet more receiver-type expertise and general wisdom); and software mavens Ken Aird and Kathryn Miknaitis from Chicago and Erik Leitch from JPL.)

Assuming that the receiver tests go well, we will be in position to couple it to the cryostat that contains the secondary mirror (which has also arrived at Pole but has not been unpacked and installed yet). And if that goes well, then it's onto the telescope with both of them, and we're off.

That's getting a bit ahead of things, but it's easy to get carried away when things are this exciting. For now, here are some pictures of the receiver and its contents.
(Thanks to Ryan for the pix.)

Adrian Lee working on the receiver focal plane (six wedges of 160 detectors each).


The fully assembled receiver on the pump and cooling down.