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First moonwalker Neil Armstrong 'doing great' after heart surgery

The first man on the moon underwent a quadruple bypass and sources have told NBC News that Armstrong's doctors expect no problems with his recovery. NBC's Brian Williams reports.

The first human to walk on the moon, Neil Armstrong, is "doing great" after undergoing cardiac bypass surgery, his wife reported.

Carol Armstrong's characterization of her husband's condition was relayed by another moonwalker, Apollo 17's Gene Cernan.

Neil Armstrong, who lives in the Cincinnati area and just celebrated his 82nd birthday, went to the hospital on Monday for a stress test. He flunked, and on Tuesday, surgeons bypassed four blockages in his coronary arteries. His wife reports that his spirits are high, and the doctors expect no problems with his recovery, Cernan told NBC News' Jay Barbree.

Armstrong became world-famous in 1969 when he and fellow Apollo 11 astronaut Buzz Aldrin landed on the moon. As the mission commander, it was Armstrong's role to step out of the lander first, descend a ladder and take the first-ever footstep on the lunar surface. "That's one small step for a man, one giant leap for mankind," he declared.

After Apollo 11, Armstrong worked briefly at the Pentagon's Office of Advanced Research and Technology, then became an engineering professor at the University of Cincinnati in his native state of Ohio. He also served as a director on the boards of several companies, and retired as chairman of the board of EDO Corp. in 2002.

Armstrong traditionally has taken a low profile in public life: His most recent turns in the spotlight came when he testified at congressional hearings on the future of NASA human spaceflight, and when he was awarded the Congressional Gold Medal last November.

In a statement, NASA Administrator Charles Bolden said the space agency "wishes Neil Armstrong the very best for a quick recovery from surgery."

"Neil's pioneering spirit will surely serve him well in this challenging time, and the entire NASA family is holding the Armstrong family in our thoughts and prayers. I know countless well-wishers around the world join us in sending get-well wishes to this true American hero," Bolden said.

Feel free to leave your get-well wishes below, and we'll pass along the general sentiment to Armstrong and his family.

Update for 5:40 p.m. ET: Armstrong's crewmate, Buzz Aldrin, is among the well-wishers: "Just heard about Neil & heart surgery today — Sending my best wishes for a speedy recovery — We agreed to make it [to] the 50th Apollo anniv[ersary] in 2019," Aldrin writes in a Twitter update.

More about Neil Armstrong:

Alan Boyle is NBCNews.com's science editor. Connect with the Cosmic Log community by "liking" the log's Facebook page, following @b0yle on Twitter and adding the Cosmic Log page to your Google+ presence. To keep up with Cosmic Log as well as NBCNews.com's other stories about science and space, sign up for the Tech & Science newsletter, delivered to your email in-box every weekday. You can also check out "The Case for Pluto," my book about the controversial dwarf planet and the search for new worlds.