To support the various telescopes and experiments here at the south pole, a ton of resources are necessary – power, heating, environmental protection, and somewhat counterintuitively, cooling. Some of the telescopes here are so sensitive, and looking at such distant signals, that in order to work properly they need to be cryogenically cooled down to just above absolute zero. The only practical way to do this is with a complex refrigerator that uses liquid helium, which sits at 4 degrees kelvin in its natural state.
Liquid helium is a dangerous, volatile, expensive substance, and in order to be able to supply the experiments with an adequate amount of it, there’s an entire cryogenics laboratory right next to the main station.
The Cryo Barn, as it’s called, is a black structure, with huge insulated loading doors. It’s about a 10 minute walk from the station.
Inside, there’s a ton of equipment surrounding huge liquid helium holding tanks. These tanks are vacuum insulated to prevent the liquid helium from boiling, and to protect people working around the tanks from being injured by the extreme cold temperature.
In order to get liquid helium over to the telescope (namely Bicep2), it must be carried in a specially designed “dewier” – a large vacuum flask. Flint transports liquid helium dewiers on the ice with a snowmobile.