Neil Armstrong has had bypass heart surgery and is now recovering in hospital Wednesday, according to reports.
The first man on the moon is reported to be doing well, and doctors have been pleased with how the operation went.
"He's doing great," Armstrong's wife, Carol, told reporters Wednesday.
The surgery came as a surprise to Armstrong; he had just been celebrating his 82nd birthday on Sunday without a hint of the problems. However, he went to hospital for a stress test on Monday and the results came back negative.
He was urgently booked in by surgeons for bypass surgery. It is reported that he had four blockages in his coronary arteries that needed bypasses, but everything went well and he is recovery according to medical plans.
Armstrong is most famous for being the first man to land a craft on the moon, and being the first man to walk on the surface of the moon. He will be forever remembered for speaking these famous words as he made his way into the moon: "That's one small step for man, one giant leap for mankind."
That historic moment took place on 10:56 p.m. EDT on July 20, 1969, and the famous message was spoken from 240,000 miles from the Earth's surface on the moon. Following his words he stepped out from the Eagle lunar landing module to make history.
Armstrong is also famous for being a command pilot for the Gemini 8 mission, which was launched on March 16, 1966. During that mission he performed the first successful docking of two vehicles in space.