(AP) - When Neil Armstrong walked on the moon all those years ago, he made his country believe that anything was possible with ingenuity and dedication _ and in the process became one of America's greatest heroes, his friends, colleagues and admirers said Saturday after news that the former astronaut had died.
"When I think of Neil, I think of someone who for our country was dedicated enough to dare greatly," said former astronaut John Glenn, who went through jungle training in Panama with Armstrong as part of the astronaut program and was a close friend. He said Armstrong showed exemplary skill and dedication.
The idea of Armstrong as a humble pilot who served his country above all echoed around the country Saturday, by visitors to museums that fete his accomplishments and by his former NASA colleagues. Armstrong died Saturday at age 82 from complications resulting from cardiovascular procedures, his family said.
In California, visitors and staff at the Griffith Observatory paused for a moment of silence. At the Armstrong Air and Space Museum in Armstrong's hometown of Wapakoneta, Ohio, a black ribbon hung over a plaque of Armstrong in the museum's entryway and a U.S. flag was lowered in Armstrong's memory.
Tourist Jonathon Lack, a judge from Anchorage, Alaska, said he decided to visit the Air and Space Museum in Washington, D.C., after hearing of Armstrong's death.
"What really hit me is that he was in his 30s when he walked on the moon," said Lack, who is 42. "That made me think about how little I've done."
He saw in Armstrong's death a reminder of an America where people dreamed big things and sought to accomplish the inconceivable.
Armstrong commanded the Apollo 11 spacecraft that landed on the moon July 20, 1969, capping the most daring of the 20th-century's scientific expeditions during the climax of a heated space race with the Soviet Union.
Armstrong and Buzz Aldrin spent nearly three hours walking on the lunar surface, collecting samples, conducting experiments and taking photographs. Aldrin, who became the public face of the moon landing after shy Armstrong recoiled from the public eye, said his colleague's leap changed the world forever and became a landmark moment in human history.
"Whenever I look at the moon, it reminds me of the moment over four decades ago when I realized that even though we were farther away from Earth than two humans had ever been, we were not alone," he said. "Virtually the entire world took that memorable journey with us. I know I am joined by millions of others in mourning the passing of a true American hero and the best pilot I ever knew."
The third astronaut on the mission, Michael Collins, circled the moon in the mother ship 60 miles overhead while the other two went to the surface. "He was the best, and I will miss him terribly," Collins said, according to NASA's website.
The Apollo 11 command module Columbia is on display at the Air and Space Museum, and visitors there Saturday gathered around it to remember Armstrong and his accomplishments.
Bob Behnken, the chief of the NASA Astronaut Office, said Armstrong's historic step was the reason many became astronauts.
"Neil Armstrong was a very personal inspiration to all of us within the astronaut office," he said. "The only thing that outshone his accomplishments was his humility about those accomplishments. "
Daniel Zhou, a student at Armstrong's alma mater Purdue University in Indiana and a member of Students for the Exploration and Development of Space, said Saturday was sad day.
"He will always be a source of inspiration for our generation, and for the generations to come, as we ask ourselves, `Why explore space?'" Zhou said.
At New York's Intrepid Sea, Air and Space Museum, a 1960 photo of Armstrong hangs near the space shuttle Enterprise _ showing a youthful NASA pilot standing and smiling next to the X-15 rocket plane he was testing.
On Saturday afternoon, many among the hundreds of visitors filing past the mammoth white display didn't know he had died.
`I'm shocked!" said Dennis McKowan, 49, a computer network engineer from Sunnyvale, Calif., on a business trip to New York. "I used to skip school to watch the Apollo launches."
He was a child when he watched the moon landing.
"How do you top that? No one has gone farther yet."
Long reported from New York. Associated Press writers Verena Dobnik in New York, Seth Borenstein and Bradley Klapper in Washington, Marcia Dunn in Cape Canaveral, Fla., and Lisa Cornwell in Cincinnati contributed to this report.
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