October 10, 2012
Nacreous clouds, observed on January 6, 2011. These polar stratospheric clouds at 80,000 feet are the highest of all clouds. They only occur in the polar regions when the stratospheric temperature dips below 100 degrees below zero Fahrenheit (-73 C). They are also the site of chemical reactions that break down ozone in the upper atmosphere and contribute to the creation of the ozone hole above Antarctica. (National Science Foundation/Kelly Speelman) Scenes From Antartica

Nacreous clouds, observed on January 6, 2011. These polar stratospheric clouds at 80,000 feet are the highest of all clouds. They only occur in the polar regions when the stratospheric temperature dips below 100 degrees below zero Fahrenheit (-73 C). They are also the site of chemical reactions that break down ozone in the upper atmosphere and contribute to the creation of the ozone hole above Antarctica. (National Science Foundation/Kelly Speelman) Scenes From Antartica

October 10, 2012
Construction crew members stand in front of the South Pole Telescope (SPT). Joshua Miller, Ryan Kunz, John R. Mallon III, Chris Kendal and Eric Nichols assembled the ground shield (the ‘squarish’ outer rim) around the 10-meter parabolic dish during the 2011-12 austral summer. The shield will help prevent ground reflection interference. The SPT is examining Cosmic Microwave Background and Dark Matter. Photo taken on January 11, 2012. (National Science Foundation/John Mallon III) Scenes from Antartica

Construction crew members stand in front of the South Pole Telescope (SPT). Joshua Miller, Ryan Kunz, John R. Mallon III, Chris Kendal and Eric Nichols assembled the ground shield (the ‘squarish’ outer rim) around the 10-meter parabolic dish during the 2011-12 austral summer. The shield will help prevent ground reflection interference. The SPT is examining Cosmic Microwave Background and Dark Matter. Photo taken on January 11, 2012. (National Science Foundation/John Mallon III) Scenes from Antartica

October 10, 2012
McMurdo Station, Antarctica, November, 2011. Original here. (CC BY Alan Light)

McMurdo Station, Antarctica, November, 2011. Original here. (CC BY Alan Light)

October 10, 2012
After a storm, the loose snow surrounding the compacted snow under a footprint is scoured away by the wind, leaving elevated strange-looking footprints. Original here. (CC BY Alan Light) Scenes From Antartica

After a storm, the loose snow surrounding the compacted snow under a footprint is scoured away by the wind, leaving elevated strange-looking footprints. Original here. (CC BY Alan Light) Scenes From Antartica

October 10, 2012
The back deck of the research vessel NATHANIEL B. PALMER is engulfed in frigid water as the ship sailed the South Atlantic Ocean, on October 1, 2011. (National Science Foundation/Dave Munroe) Scenes From Antartica via InFocus

The back deck of the research vessel NATHANIEL B. PALMER is engulfed in frigid water as the ship sailed the South Atlantic Ocean, on October 1, 2011. (National Science Foundation/Dave Munroe) Scenes From Antartica via InFocus