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Image credit: Patrick Cullis, National Science Foundation

“The photo, captured above the new elevated station at Amundsen-Scott South Pole Station in July 2009, is a 20-minute exposure revealing the southern celestial axis — the white cloudy streak is the Milky Way. Only at the North and South Poles will you witness a phenomenon exactly like this, as the stars’ ‘movement’ across the sky demonstrates the Earth’s rotation in stunning detail.”

So why can astronomers view the milky way galaxy so ostensively compared to other places on the planet? Well, the dry cold air found in both the North and South Poles allows cosmic microwave background (CMB) radiation, i.e. “the afterglow of the big bang”, to pass through or be observed with minimal interference from water vapor. Cosmic microwave background (CMB) radiation, regarding the electromagnetic spectrum, falls somewhere between heat radiation and radio waves. Even though both Poles could house astronomical equipment, the South Pole has significantly more solid ice to build structures upon, compared to the North Pole. Another boon of housing astronomical equipment in the South Pole lies in the lack of, well, light pollution.