Ridge A

Description

Ridge A is a site in Antarctica that was identified in 2009 as the best suited location on the surface of Earth for astronomical research. The site, approximately 1,000 kilometres (620 mi) from the South Pole and 144 kilometres (89 mi) southeast of Dome A, is situated in a portion of Antarctica claimed by Australia in the Australian Antarctic Territory.

The site is on the Antarctic Plateau at an altitude of 4,053 metres (13,297 ft), and has an average winter temperature of −70 °C (−94 °F). It is possible that this site may have even lower temperatures than Dome A. Ridge A was identified by a team of Australian and American scientists searching for the best observatory spot in the world. The team leader described the site as "so calm there's almost no wind or weather there at all." Ridge A is a low ridge of ice and has been estimated to have very low disturbances to visibility, such as thick atmospheric boundary layer, amount of water vapour and numerous others.

The site represents the "Eye of the Storm", whereby winds flowing off Antarctica in all directions appear to start from a point at Ridge A, where winds are at their calmest. It is also the site of a vortex in which swirling stratospheric winds high up and calm air at ground level combine to make it a place for viewing into space that is three times clearer than any other location on Earth.