Astronaut Bruce McCandless II, wearing a Shuttle Extravehicular Activity (EVA) Suit with Manned Maneuvering Unit (MMU) in Houston in 1982. Picture: NASA via AP

Washington - US astronaut Bruce McCandless, the first person to free-float untethered on a spacewalk, has died at the age of 80, NASA confirmed on Friday.

During the 1969 Apollo II mission, McCandless also served as the Mission Control communicator for Neil Armstrong and Buzz Aldrin, who became the first men to walk on the moon.

A retired US Navy captain, McCandless joined NASA in 1966, becoming a member of the astronaut support crew for the Apollo 14 mission and backup pilot for the first crew Skylab mission.

This Feb. 7, 1984 photo made available by NASA shows astronaut Bruce McCandless II, participating in a spacewalk a few meters away from the cabin of the Earth-orbiting space shuttle Challenger, using a nitrogen-propelled Manned Maneuvering Unit. Picture: NASA via AP

He performed his famous spacewalk in 1984 and in 1990 helped deploy the Hubble Space telescope, which was launched to investigate far-off galaxies.

McCandless died on Thursday.