CINCINNATI — Neil Armstrong was a soft-spoken engineer who became a global hero when as a steely-nerved pilot he made “one giant leap for mankind” with a small step onto the moon. The modest man, who had people on Earth entranced and awed from almost a quarter-million miles away, but credited others for the feat, died Saturday. He was 82.

Armstrong died following complications resulting from cardiovascular procedures, his family said in a statement. Armstrong had had a bypass operation this month, according to NASA. His family didn’t say where he died; he had lived in suburban Cincinnati.

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. His first words after becoming the first person to set foot on the surface are etched in history books and the memories of those who heard them in a live broadcast.

“That’s one small step for man, one giant leap for mankind,” Armstrong said.

(Armstrong insisted later that he had said “a” before man, but said he too couldn’t hear it in the version that went to the world.)

In those first few moments on the moon, during the climax of a heated space race with the then-Soviet Union, Armstrong stopped in what he called “a tender moment” and left a patch to commemorate NASA astronauts and Soviet cosmonauts who had died in action.

“It was special and memorable but it was only instantaneous because there was work to do,” Armstrong told an Australian television interviewer this year.

Armstrong and Buzz Aldrin spent nearly three hours walking on the lunar surface, collecting samples, conducting experiments and taking photographs.

“The sights were simply magnificent, beyond any visual experience that I had ever been exposed to,” Armstrong once said.

The moonwalk marked America’s victory in the Cold War space race that began Oct. 4, 1957, with the launch of the Soviet Union’s Sputnik 1, a 184-pound satellite that sent shock waves around the world.

Although he had been a Navy fighter pilot, a test pilot for NASA’s forerunner and an astronaut, Armstrong never allowed himself to be caught up in the celebrity and glamour of the space program.

“I am, and ever will be, a white socks, pocket protector, nerdy engineer,” he said in 2000 in one of his rare public appearances. “And I take a substantial amount of pride in the accomplishments of my profession.”

Fellow Ohioan and astronaut John Glenn, one of Armstrong’s closest friends, recalled Saturday how Armstrong was down to the last 15 seconds to 35 seconds of fuel when he finally brought the Eagle down on the Sea of Tranquility.

“That showed a dedication to what he was doing that was admirable,” Glenn said.

A man who kept away from cameras, Armstrong went public in 2010 with his concerns about President Barack Obama’s space policy that shifted attention away from a return to the moon and emphasized private companies developing spaceships. He testified before Congress and in an email to The Associated Press, Armstrong said he had “substantial reservations,” and along with more than two dozen Apollo-era veterans, he signed a letter calling the plan a “misguided proposal that forces NASA out of human space operations for the foreseeable future.”

Armstrong was among the greatest of American heroes, Obama said in a statement.

“When he and his fellow crew members lifted off aboard Apollo 11 in 1969, they carried with them the aspirations of an entire nation. They set out to show the world that the American spirit can see beyond what seems unimaginable — that with enough drive and ingenuity, anything is possible,” Obama said.

Obama’s Republican opponent Mitt Romney echoed those sentiments, calling Armstrong an American hero whose passion for space, science and discovery will inspire him for the rest of his life.

“With courage unmeasured and unbounded love for his country, he walked where man had never walked before. The moon will miss its first son of earth,” Romney said.

NASA chief Charles Bolden recalled Armstrong’s grace and humility.

“As long as there are history books, Neil Armstrong will be included in them, remembered for taking humankind’s first small step on a world beyond our own,” Bolden said in a statement.

Armstrong’s modesty and self-effacing manner never faded.

When he appeared in Dayton in 2003 to help celebrate the 100th anniversary of powered flight, he bounded onto a stage before 10,000 people packed into a baseball stadium. But he spoke for only a few seconds, did not mention the moon, and quickly ducked out of the spotlight.

He later joined Glenn, by then a senator, to lay wreaths on the graves of Wilbur and Orville Wright. Glenn introduced Armstrong and noted it was 34 years to the day that Armstrong had walked on the moon.

“Thank you, John. Thirty-four years?” Armstrong quipped, as if he hadn’t given it a thought.

At another joint appearance, the two embraced and Glenn commented: “To this day, he’s the one person on Earth, I’m truly, truly envious of.”

Armstrong’s moonwalk capped a series of accomplishments that included piloting the X-15 rocket plane and making the first space docking during the Gemini 8 mission, which included a successful emergency splashdown.

In the years afterward, Armstrong retreated to the quiet of the classroom and his southwest Ohio farm. Aldrin said in his book “Men from Earth” that Armstrong was one of the quietest, most private men he had ever met.

In the Australian interview, Armstrong acknowledged that “now and then I miss the excitement about being in the cockpit of an airplane and doing new things.”