Gene Cernan, a US astronaut who was the last man to step foot on the moon, died Monday. He was 82.
NASA announced his death in a tweet Monday morning. The cause of death was not revealed.
"We are saddened by the loss of retired NASA astronaut Gene Cernan, the last man to walk on the moon," the agency said on its official Twitter account. Cernan's death comes less than six weeks after the death another American space hero, John Glenn, who in 1962 became the first American to orbit the Earth.
Cernan joined NASA in 1963 and went on to make significant contributions to the space program during his 14-year astronaut career. He went into space three times, for the first time as a pilot during the three-day Gemini 9 mission in 1966. During this mission, Cernan became the second American to walk in space, logging more than two hours outside the spacecraft.
Cernan's second journey into space was as the lunar module pilot of Apollo 10 in 1969, which was considered the dress rehearsal for the first moon landing because it achieved all the necessary objectives short of an actual lunar landing. During the mission, the lunar module entered an orbit 8.4 nautical miles from the moon's surface, the point at which a descent for landing would begin.
"I keep telling Neil Armstrong that we painted that white line in the sky all the way to the Moon down to 47,000 feet so he wouldn't get lost, and all he had to do was land," Cernan said in a NASA interview in 2007. "Made it sort of easy for him."
His last trip to space was as commander of Apollo 17 in 1972, the last scheduled US manned mission to the moon. The mission crew set several records for human space flight, including the longest lunar landing flight (301 hours, 51 minutes); longest lunar surface extravehicular activities (22 hours, 6 minutes); largest lunar sample return (nearly 249 pounds) and longest time in lunar orbit (147 hours, 48 minutes), according to a NASA bio on Cernan.
On its way to the moon, the crew captured the iconic "Blue Marble" photo of Earth, showing the Mediterranean Sea area to the Antarctica South polar ice cap. This was the first time a spacecraft's trajectory allowed astronauts to photograph the South polar ice cap.
During this mission, Cernan became the 11th man to walk on the moon as well as the last to leave his footprints on its surface. As he left the moon for the journey back to Earth, he voiced hope that one day man would return to the moon.
"America's challenge of today has forged man's destiny of tomorrow," Cernan said. "As we leave the moon and Taurus-Littrow [mountains], we leave as we came, and, God willing, we shall return, with peace and hope for all mankind."
In all, Cernan logged more than 566 hours in space -- 73 hours of which were spent on the surface of the moon.
Eugene "Gene" Cernan was born March 14, 1934, Chicago. He earned a Bachelor of Science degree in electrical engineering from Purdue University in 1956 and a Master of Science degree in aeronautical engineering from the US Naval Postgraduate School in Monterey, California.
Following his retirement from the space program in 1976, Cernan worked in energy, aerospace and other related industries. He also served as a co-anchorman of ABC-TV's presentations of the flight of the shuttle.
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