Geek Cool:

Before there were computer simulators for training...

...we still managed to land on the moon.

Here is one of the ways NASA overcame the difficulties presented by the last 300 feet to the moon.

One of my earliest memories is watching a fuzzy picture on the TV in the living room, a man in a bulky white space suit walking on the surface of the moon. It is one memory I hope I never lose.

It was thirty-five years ago:

On July 16, Armstrong, Aldrin and Collins climbed into the Apollo. The unit's Saturn V rocket, equipped with the most powerful engines ever built, blasted them into space.

Their trajectory took them around Earth and toward the moon when a third-stage rocket fired. Two modules -- the Eagle, for landing, and the Columbia, a command and service center -- entered the moon's orbit July 19.

A day later, Armstrong navigated a course that included a potentially deadly crater and boulder field before successfully touching down in flat terrain.

"Houston, Tranquility Base here," he said. "The Eagle has landed."

Armstrong, soon joined by Aldrin, spent 21 hours on the lunar surface. The two sampled rocks, surveyed terrain, set up experiments and famously planted an American flag in the soil. A plaque they left read: "Here men from the planet Earth first set foot upon the Moon. July 1969 AD. We came in peace for all mankind."

The pair then re-entered the Eagle, reuniting with Collins and the Columbia module before returning home by splashing down in the Pacific Ocean.

Within six months, the United States had landed a second team of astronauts on the moon. For the next three years, at six-month intervals, NASA sent more manned missions to the moon. The sixth and final one, Apollo 17, left the moon December 14, 1972 -- the last time humans set foot on another celestial body.

Apollo 11, and the six subsequent lunar missions (except for Apollo 13, during which U.S. astronauts averted disaster but returned home without setting foot on the moon), marked a stunning climax after years of tribulations and smaller successes.

The U.S. space program, under the Pioneer and Ranger missions, made repeated attempts to hurl a satellite toward the moon starting in 1958. The first 10 U.S. robotic missions to the moon failed due to booster rocket misfires, faulty computers and other malfunctions.

On July 28, 1964, Ranger 7 finally succeeded. The craft beamed 4,316 images back to Earth before crashing on the lunar surface. More fly-bys and reconnaissance missions followed, paving the way for Apollo 11.