Sunday, December 21, 2014
Another week has passed, and things are starting to feel like Christmas here! Last weekend the station decorated the galley (dining hall) with a full-sized (fake) Christmas tree, Christmas wreathes, and various decorations along the windowsills. My favorite is a family of ice skating penguins, happily cavorting in front of the view of the snow-covered plains surrounding the station.
There are a variety of Christmas activities planned for next week – from screenings of Christmas movies to a cookie-decorating party to caroling over the radio with McMurdo – and everyone has signed up for Christmas dinner on Thursday. I’m hoping to go to at least some of the activities leading up to Christmas Day, but I probably won’t have time for all of them – because it looks like the Keck team may finally have some real work to do! Both of our focal planes left the US last night with Bryan, the latest member of our team to deploy, and are officially en route to Pole. This means that we can finally start preparing for their arrival, which will be several days of hard work. We have to take two telescope receivers out of the mount, warm them up to room temperature, and open them up all the way to the innermost section where the focal planes sit. In addition to putting the new focal planes in, we will be replacing the lenses and filters in the telescope tube with new optics that are optimized for 220 GHz. If we are very lucky with the weather, the focal planes could arrive before Christmas – in which case we will all keep working through the holiday to install them and get ready to test them before putting the reassembled receivers back into the telescope mount. If the weather doesn’t cooperate, then Bryan won’t arrive until after Christmas and we will have time to relax until he gets here. I’m scheduled to leave on the first plane after Christmas, so either way I will probably only cross paths with the focal planes briefly.
Other than the big news about the focal planes, there isn’t much to report on the work front about Keck. Last week we replaced the clear plastic membrane in front of one of the telescope receivers that we use to keep snow out of the optics (because last summer it broke and was replaced with the wrong kind of plastic, which made data from that receiver extra noisy all year), so this week the main thing I did was take some observations to make sure that the new membrane is working correctly. I ran up against the limitations of the computers here while attempting to analyze some of this test data – data reduction that would normally take only a few hours to run on Harvard’s computers instead took over a day – but it looks like the new membrane is indeed better than the old one. I spent the rest of the week helping out with BICEP3, which is continuing to take shape. The most interesting part of this was helping out with the BICEP3 groundshield, which is a 5,800-pound aluminum construction that will surround the BICEP3 telescope receiver on the roof of DSL. The groundshield – as one might expect given the name – blocks the telescope from seeing emission from the ground. (Since the ground, while cold, is still warmer than the microwave sky and therefore emits lots of microwave radiation, we need to make sure that radiation from the ground doesn’t overwhelm the radiation from the sky that we are trying to observe.) I helped cover the seams between the sheets of aluminum with metal aluminum tape and helped with a “tip test” in which we jacked up one side of the groundshield to verify that the entire construction is stable when it is tilted. Tilting the groundshield will need to be done once per summer, so that BICEP3’s far-field focus can be calibrated.
In non-work news, the most exciting event of the week was the three-hour visit of a Congressional delegation. Ten members of the House of Representatives, several congressional aides, and several top members of the National Science Foundation visited as part of a multi-day tour of US science operations in Antarctica. We heard rumors that the NSF is angling for more funding to upgrade facilities in McMurdo, while some of the Congressmen had a different agenda – finding and eliminating examples of wasteful government spending. So it will be interesting to see what, if anything, comes out of this visit. The delegation was originally planning to spend a full afternoon here and get a tour of the telescopes, but due to bad weather their time on the continent was cut short by a day, which resulted in a shorter visit here. So instead, they arrived around lunchtime and went straight to the South Pole markers for photos – while everyone watched from the galley and made fun of the fact that they were chauffeured to the Pole in a train of vehicles because no one trusted them to walk the few hundred feet there from the runway – and then got a quick tour of the main station. As part of their tour they came through the Science Lab, which is a space set aside on the main station for scientists to do work. We use our workspace there for analysis and to check up on our telescopes without having to go all the way out to MAPO and DSL. Our group shares the space with several other collaborations, including the South Pole Telescope (SPT), IceCube (a neutrino experiment), and SPIceCore (a group drilling hundreds of feet into the ice cap to extract ice cores that date back thousands of years). Each group sent representatives to briefly summarize their science to the delegation. John Carlstrom, the PI of the South Pole Telescope, gave an overview of CMB science at the South Pole. He asked all of the BICEP/Keck and SPT scientists to be present during the tour, both to make a good impression and so that he could show off how many students are making “key contributions” to our science. I got to shake a few hands, but otherwise had very little chance to interact with any of the visitors before they were whisked away back to their airplane.
In other non-work news, I tried two new fun recreational activities this week: sledding and going to the station sauna. Kimmy, one of the BICEP3 grad students, had her birthday on Thursday, so to celebrate a group of us quit work early and went sledding. We borrowed a cargo sled from one of the snowmobiles parked in front of DSL and rode it down the giant mountain of snow next to the building. The top was approximately level with the roof of DSL, so we picked up some decent speed (and had a great view). With five or six people piled into the plastic sled, we managed to go quite a long distance.
On Friday I visited the sauna for the first time. Apparently “CMB sauna night” is a group tradition, but this was the first time we held one this season. I’ve never really liked saunas, but I now understand why people enjoy them – the humidity was a welcome change from the extremely dry ambient environment here, and the heat was made tolerable by the fact that one could periodically run outside to cool off. Even though it was -15F and windy, we found that we could stay out for five minutes or so without discomfort. Another tradition is running straight from the sauna out to the Pole in bathing suits and taking photos, but it was too windy for that on Friday. During the winter, especially adventurous people join the “300 Club” by running from the (+200F) sauna to the Pole and back when the outside temperature drops below -100F. It never gets that cold during the summer, but I hope to join the “200 Club” before I leave.
Next Saturday, if the weather cooperates, I will fly from the South Pole back to McMurdo on the first leg of my trip home. If I have no weather delays at all, I will be back in Boston on December 30th. However, weather is one thing that no one can take for granted here – so I could very well be in Antarctica for an extra week or more. Stay tuned!