Former American astronaut
Aldrin, 86, was visiting the South Pole as part of a private tourist group when his health deteriorated, the International Assn. of Antarctica Tour Operators said on its website.
It said he was taken as a precaution on the first available flight to McMurdo Station, a U.S. research center on the Antarctic coast. It described his condition as stable.
The National Science Foundation, which manages the U.S. Antarctic program, described Aldrin as "ailing" and said he was being flown on a ski-equipped LC-130 cargo plane to McMurdo. From there, he would be flown to New Zealand, it said on its website.
Aldrin became the second man to walk on the moon in 1969 as part of the U.S. Apollo 11 mission.