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MOON LANDING FACTS: Apollo 11 at

40

July 16, 1969: The world watched in anticipation as three men were

hurtled skyward in a rocket bound for the moon.

The Apollo 11 launch date had arrived with just months to spare:

Nine years earlier, U.S. President John F. Kennedy had said that by

the end of the decade the country would put a man on the moon

and return him safely to Earth.

Shortly after Kennedy's speech, an intensive effort got under way to

prepare humans for a moon landing.

In January 1963 Neil Armstrong and four other Apollo astronauts

took a field trip to Arizona's Meteor Crater and Sunset Crater, a

dormant volcano. Geologists then briefed the astronauts on how

those Earthly landscapes were similar to what they might encounter

on the moon.

In the years that followed, Apollo crew also toured the Grand

Canyon and spent time testing lunar rovers at Bonito Crater

northeast of Flagstaff, where the rough, rocky surface mimicked

what some geologists thought would exist on the moon.

Geologists flew over Sunset Crater and other landforms in Cessna

182s, taking aerial photos so the astronauts might better

understand the lunar geology they were likely to see.

The Apollo moon-landing program was named for the son of Zeus in Greek mythology, often known as the god of light and the sun.

But the first mission almost brought U.S. moon-landing efforts to an

abrupt end.

On January 27, 1967, a flash fire occurred in the Apollo 1 command

module during a launch simulation, killing the three astronauts

meant to pilot the mission.

"I wasn't sure if we were burying the entire Apollo program or three

of our buddies," Apollo astronaut Gene Cernan said in In the

Shadow of the Moon.

Following an exhaustive investigation into the accident, NASA

issued a report in April 1967 that called for major overhauls of the

Apollo hardware, launch procedures, and quality control.

The program swung back into gear, and by early 1969, Apollo 10

astronauts Alan Shepard and Donald "Deke" Slayton were cruising

over the lunar surface—and grudgingly holding back from diving

down for a landing—as they scoped out the Sea of Tranquility, the

chosen landing spot for Apollo 11.

A few months later, Apollo 11 astronauts Neil Armstrong, Buzz

Aldrin, and Michael Collins set off toward the moon.

Moonwalkers

Launched from Florida's Kennedy Space Center at 9:32 a.m. ET

aboard a Saturn V rocket, Apollo 11 included a command module

dubbed Columbia and a lunar lander called the Eagle.

The lander was named after the bald eagle in the mission insignia.

Apollo 11's journey to the moon took three and a half days.

During that time the astronauts "just kind of gazed out the window

at the Earth getting smaller and smaller, did housekeeping things,

checking the spacecraft," Aldrin recalled.

As the craft passed through the shadow of the moon and started its

approach, Aldrin and Armstrong got into the spider-like lunar

module and began their descent.

The landing process didn't go flawlessly. Alarms sounded when the

computer couldn't keep up with the data stream: "Nothing

serious—it was distracting," Aldrin said.

"Neil didn't like what we were heading toward, and we selected a

safer spot alongside a crater with boulders in it. We landed with a

little less fuel than we would have liked to have had, maybe 20

seconds of fuel left."

Aldrin insists that he felt no real fear about landing on the moon.

Nevertheless, he said, "we kind of practiced liftoff [for] the first two

hours. … We both felt that was the most prudent thing to do after

touching down, was to prepare to depart if we had to."

Finally, with half a billion people watching on televisions across the

world, the astronauts emerged from the Eagle to spend another two

hours exploring the lunar surface.

The pair planted an American flag and placed mementos for fallen

peers.

Armstrong uttered his famous first words, reportedly unscripted:

"That's one small step for man, one giant leap for mankind."

Armstrong and Aldrin logged 21 hours on the moon—spending the

last and longest portion of it trying to sleep in the frigid lander. Then

they lifted off to rendezvous with Collins and Columbia for the return

voyage.