US astronaut John Young passes away

The National Aeronautics and Space Administration (NASA) on Saturday said, "We're saddened by the loss of astronaut John Young."

Young was the first person to travel to space six times and the ninth of 12 scientists to set foot on the lunar surface.

"NASA and the world have lost a pioneer. Young was at the forefront of human space exploration with his poise, talent, and tenacity. He was in every way the 'astronaut's astronaut'," said NASA acting administrator Robert Lightfoot, local media reported.

Local media stated that the octogenarian died of pneumonia.

Young was one of the three astronauts to travel twice to the moon.

The former US Navy test pilot flew into space twice during the Gemini programme of NASA in 1960's and twice on space shuttles.

Young was the longest serving astronaut, who worked with NASA for 42 years.

In an interview, after his retirement in 2004, he said that he considered himself "very lucky".