Astronomers have been building telescopes in extreme locations for decades, sacrificing accessibility and comfort for better observing conditions. No location is more extreme than Antarctica, home of the South Pole Telescope (SPT), an instrument designed to observe the Cosmic Microwave Background, light from the universe when it was only 380,000 years old.
In November 2018, Matt Young, a PhD student in the Department of Astronomy & Astrophysics in the Faculty of Arts & Science at U of T, travelled to the Amundsen-Scott South Pole Station for the second time in two years to work on the SPT. Via emails from the South Pole, Young described to Arts & Science News what he was working on and what it was like to work and live for two months in one of the most inhospitable locations on Earth.
How and when did you first become interested in astronomy as a career?
I’ve been interested in astronomy for as long as I can remember. I was really lucky growing up in Western Australia where the night sky can be breathtaking and I spent countless nights as a kid just lying on a trampoline, staring at the stars. Growing up, I’d always wanted to be a scientist, and as an undergrad I studied both astrophysics and engineering. Then, towards the end of my undergraduate studies I learned I could use the skills I gained as an engineer in the scientific field I was passionate about. So, after an exchange program in Canada, I decided to pursue my graduate studies in astrophysics at U of T.
What are your current research interests?
My two main research interests are cosmology and instrumentation, and working on the SPT combines both. Cosmology looks at the universe as a whole — its birth, its evolution, and everything in it. Astronomical instrumentation covers the huge array of different telescope and camera technologies we develop and use to study the universe around us, from radio telescopes in remote deserts to X-ray telescopes orbiting in space.
What are you working on during this trip?
This year, we’re working on upgrading the SPT’s new camera that was installed onto the telescope in early 2017. Several of the detectors are being replaced with improved versions that we developed over the past year. We’re also installing a new structure for holding the camera’s detectors and electronics. The detectors and electronics are extremely sensitive to vibrations and small changes in temperature inside the camera and the new structure drastically reduces these effects.
Why are cosmologists at the South Pole of all places?
The South Pole is definitely one of the most harsh and remote locations you could put a telescope, but it’s also one of the best places on Earth for observing microwaves coming from space. First, the South Pole is almost three kilometres above sea level on a plateau of frozen ice that covers most of the continent. The atmosphere interferes with many astronomical signals we want to measure, and so many telescopes benefit by being placed at high altitudes where the atmosphere is much thinner. Second, microwaves from space are absorbed by water vapour, but the South Pole is incredibly dry, with close to zero water vapour in the atmosphere. And third, with six months of daylight and six months of darkness, the atmosphere is relatively stable without the daily cycle of heating and cooling.
What do astronomers hope to discover with the SPT?
The Cosmic Microwave Background provides us with a valuable tool for probing the conditions of the early universe. The SPT’s camera is mapping the CMB’s temperature with better precision than any other microwave telescope. This makes the SPT well suited to particular science goals, such as probing the matter that lies between us and the CMB. It’s also a powerful tool for locating galaxy clusters, some of the most massive structures in the cosmos. Clusters of galaxies are so massive that they imprint a unique ‘shadow’ on the CMB. We are able to discover new galaxy clusters by looking for these unique imprints and we hope SPT will eventually find thousands of previously undiscovered galaxy clusters.
What’s it like down there?
Without a doubt, it’s colder than anything I’ve ever experienced, averaging -30C to -40C over the Antarctic summer. Exposed skin freezes quickly without proper protection, especially in high winds. Also, the air is thinner, so even light physical activity can leave you gasping for breath.
One of the hardest parts about being down here is being unable to contact the outside world for large chunks of the day since communication depends on a satellite which is not always within line of sight. Plus, fresh fruit and vegetables are scarce and can become a bit of a luxury. Occasionally a flight will arrive with a shipment of “freshies,” resulting in much excitement at the possibility of a salad with dinner!
How do you feel about your Antarctic adventures?
I feel incredibly lucky that my grad studies have allowed me to visit somewhere very few people will ever have the opportunity to go to. And while the South Pole is an incredible and special place, it’s comforting that most people who live and work here are regular people who’ve simply decided to take a job at the bottom of the world. This mix of people from all sorts of professions and backgrounds really helps build a supportive community that makes the South Pole feel like a home — something that’s very important when most people live here for months on end.
On my first trip down last year, I really got to appreciate the novel experience of setting foot at the southern-most point on the globe, and marvelled at the expanse of flat ice and snow that extends for hundreds of kilometres in every direction. For my visit this year, I had a chance to get more involved in the South Pole community. So, while just setting foot at the South Pole is an incredible experience in itself, the opportunity to be a part of this amazing and hard-working community is the best part of the journey.