Apollo 11 moonwalker Buzz Aldrin was evacuated today (Dec. 1) from the South Pole due to illness, where he had been visiting as part of a tourist group.

Aldrin is 86 years old, and was the second man to walk on the moon (after Neil Armstrong) during NASA's historic Apollo 11 lunar landing mission in July 1969. According to a Twitter post by Aldrin, he departed for the South Pole on Tuesday (Nov. 29). The tourism operator White Desert reported that Aldrin was in stable condition when he was evacuated to McMurdo Station, on the Antarctic coast, by the U.S. Antarctic Program. He was under the care of a doctor from the program, they said.

"The National Science Foundation (NSF) has agreed to provide a humanitarian medical evacuation flight for an ailing visitor from its Amundsen-Scott South Pole Station to McMurdo Station on the Antarctic coast and then to New Zealand," the National Science Foundation said in a statement. "The flight to New Zealand will be scheduled as soon as possible."

The NSF said that they will make additional statements about Aldrin's medical condition if warranted.

Since his retirement from NASA, Aldrin has been an active proponent of Mars colonization.

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