The South Pole is probably among the "harshest environments" on earth. Those who fall ill here cannot just visit a local doctor, but need to contact multiple agencies. Even evacuation from here might require multiple airplanes.

Recently, a medical evacuation mission was announced by The National Science Foundation for one of the 48 members in the South Pole.

"After comprehensive consultation with outside medical professionals, agency officials decided that a medical situation at Amundsen-Scott South Pole Station warrants returning a member of the station's winter crew to a hospital that can provide a level of medical care that is unavailable at the station," the NSF said.

The mission was launched this morning in Calgary, Canada, on a couple of Twin Otter aircraft run by Kenn Borek Air. The Canadian firm offers contractual logistical support to the Antarctic Program.

The Twin Otter aircraft is designed in such a way that it helps people that "operate in extremely low temperatures and are able to land on skis," the NSF said.

As a runway is lacking at Amundsen-Scott Station, the aircraft will land on compacted snow in complete darkness.

Both planes will fly from Canada to South America and finally land at Rothera, which is a research station almost 2,000 kilometers due south of Argentina on the Antarctic Peninsula. It will be managed by the British Antarctic Survey. One aircraft will fly for another 1,500 miles to the South Pole to take up an NSF member. But the other aircraft will remain behind at Rothera in order to help with search-and-rescue missions, according to the officials.

Two similar medevac missions were navigated to the South Pole in 2001 and 2003. However, like other flights between February and October, which is Antarctica's winter season, the mission is expected to be impacted by the weather here.

"The mission will be highly weather-dependent and the current best-case scenario is that a plane would arrive at Amundsen-Scott South Pole Station no sooner than June 19," the NSF said.

"Because of the complexity of the operation, the evacuation will require contributions from multiple entities involved in the U.S. Antarctic Program including weather forecasts from the U.S. Navy's Space and Naval Warfare Systems (SPAWAR) Center Atlantic; expertise from the University of Texas Medical Branch; and various contributions from ASC, NSF's Colorado-based Antarctic logistics contractor as well as assistance from other nations," the NSF added.

While further information about the NSF member is not known, the patient is "seasonally employed through the Lockheed Martin Antarctic Support Contract."

The NSF operates Amundsen-Scott as one of three year-round stations. People working here are isolated. "You have to be extra careful all the time [and] more safety-minded than we are back home," says Katy Jensen, a site manager who has spent three winters at Amundsen-Scott. "You're utterly relying on each other, especially for emergency situations."