Retired astronaut Buzz Aldrin, the second man to walk on the Moon, was recovering in a New Zealand hospital Friday after being medically evacuated from the South Pole while on a tourist trip, his management said.

Aldrin, 86, was "evacuated on the first available flight out" after experiencing health problems, said a statement from Antarctic tour operator White Desert.

It said Aldrin -- later found to have fluid on his lungs -- was flown out after his "condition deteriorated", describing the move as "a precaution."

An update on Aldrin's website said he was taken to Christchurch, New Zealand, where he was receiving hospital treatment.

"(He) currently has fluid in his lungs but is responding well to antibiotics and being kept in overnight for observation," it said.

"His condition is stable and his manager, who is currently with him, described him being in good spirits."

Aldrin's management also tweeted a photograph of the spaceman smiling and looking alert in his hospital bed.

His illness in the remote frozen continent sparked a 4,400 kilometre (2,700 mile) mercy dash.

First, the US National Science Foundation dispatched a humanitarian medical flight to the Amundsen-Scott South Pole Station.

From there, another flight took Aldrin to McMurdo Station on the Antarctic coast, and then to New Zealand, where he arrived at 4:25 am local time Friday.

"After a gruelling 24 hours we're safe in New Zealand," his manager Christina Korp tweeted.

- 'Here I come' -

In 1969, Aldrin and Neil Armstrong became the first men to walk on the Moon, as part of the Apollo 11 mission.

Armstrong stepped out of the lunar module first, uttering the now famous words, "That's one small step for man, one giant leap for mankind."

Aldrin, clad in a bulky white spacesuit, hopped out next.

"Beautiful, beautiful. Magnificent desolation," Aldrin said on July 20, 1969.

In recent years, he has authored books for adults and children and advocated establishing a permanent human colony on Mars.

Aldrin is an avid user of Twitter, and tweeted in recent days about his trip to the South Pole.

"I could be a little underdressed for Antarctica. Although I tend to be hot blooded," he wrote on November 27, posting a picture of himself wearing a black and red Mars shirt.

"South Pole, here I come!" he wrote a day later.

Born in Montclair, New Jersey on January 20, 1930, Aldrin was educated at the prestigious West Point military academy in New York state.

He joined the US Air Force and flew 66 combat missions in the Korean War, shooting down two enemy fighter jets.

He earned a doctorate in astronautics from the Massachusetts Institute of Technology, and devised manned space rendezvous techniques -- an orbital maneuvre during which two crafts dock in space -- that were later adopted by NASA.

In 1963, he was picked to join the select corps of early US astronauts, and six years later he set a record -- now broken -- for the longest space walk by spending five and a half hours outside the spacecraft during the Gemini 12 orbital mission.

He logged a total of 4,500 hours flying time, 290 of them in space.

Aldrin is known to be a Republican and a devout Christian, and has said he took communion while in the spacecraft that landed on the Moon. He has been married and divorced three times and has three children.