Buzz Aldrin, the second man on the Moon, has been evacuated from the South Pole after falling ill.
The former 86-year-old astronaut was visiting Antarctica in a tourist group and was evacuated to the US Antarctic Program's research centre.
The White Desert tour company said Mr Aldrin was stable under the care of a doctor, according to BBC report.
The evacuation flight was provided by the National Science Foundation who said Mr Aldrin was "ailing".
In a statement on their website, White Desert said Mr Aldrin's condition had "deteriorated". They said Mr Aldrin was evacuated as a "precaution" and had been "accompanied by a member of his team".
Mr Aldrin had tweeted about the tour just a few days earlier.