South Pole Offers Prime Astronomy Real Estate

The middle of the world's most remote and inhospitable continent may not seem like an ideal place to conduct complicated scientific research, but this photo shows how the South Pole offers advantages that astronomers and other researchers just can't find anywhere else.

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.

The North Pole sits on a patch of frozen ocean, making large installations implausible. The South Pole, however, is on solid ground (in fact, two miles of solid ice atop solid ground). Scientists can study a fixed point in the sky for months or even years, in contrast to the middle latitudes where stars eventually 'move' behind the horizon within a few hours.

There are other reasons why the South Pole is a prime location for studying the cosmos. Months of darkness during the winter give ample opportunities for exploring the skies, and its desolate location means light pollution from buildings and streetlamps isn't much of a concern.

For example, dry, cold air allows cosmic microwave background (CMB) radiation, the afterglow of the Big Bang, to be observed with minimal interference from water vapor. On the electromagnetic spectrum, the CMB falls somewhere between heat radiation and radio waves. The CMB is largely uniform, but it contains tiny ripples of varying density and temperature. These ripples reflect the seeds that, through gravitational attraction, grew into the galaxies and galaxy clusters visible to astronomers today.

In 2007, the 22.8-meter-tall South Pole Telescope was opened to examine CMB waves for clues about the origins of the universe.

- Dana Cruikshank , NSF

Image credit: Patrick Cullis, National Science Foundation