Forty-three years ago today, Neil Armstrong took that historic "one small step for man". Actually, it wasn't a small step - he landed the lunar module Eagle so gently that its shock absorbers didn't compress; so he had to jump three-and-a-half feet from the ladder to the Moon's surface. But it was only recently that the true extent of Apollo 11's audacity was revealed, when the National Aeronautics and Space Administration (Nasa) de-classified several Apollo documents. They show the technological complexities and enormous risks that faced the first Moon landing mission. Astronauts Armstrong, Edwin Aldrin and Michael Collins were admittedly prepared for the worst on July 16, 1969, as they rode the Saturn V rocket, the most powerful machine ever built, into Earth's orbit en route to the Moon.
During those momentous days, Nasa claimed it had planned Apollo 11 impeccably, even publishing the mission profile months in advance. Freed from Earth's gravity, Apollo 11's momentum would 'sling' it moonward to be captured by lunar gravity. The spacecraft would then fire its engine to slow down and enter a 60-mile-high Moon orbit. After circling the Moon a dozen times, Armstrong and Aldrin in Eagle would separate from the command module, Columbia, to descend to the Moon, leaving Collins in orbit in Columbia. When Eagle took off from the moon, it would dock with Columbia and return to Earth.
It looked perfect on paper, but it turns out that Nasa was secretly worried about hidden risks in the mission. Besides the launch - Saturn V carried enough fuel to throw a 100-pound shrapnel for three miles if it blew up on launch (and the fire aboard Apollo 1, which killed its three crew on the launch pad on January 27, 1967, still haunted Nasa) - Apollo 11 faced several perilous phases. As it happened, when Eagle carrying Armstrong and Aldrin undocked from Columbia for their powered descent to the Moon's surface, the cabin was not fully depressurised, which threw the lander four miles off target.
Seven miles from the surface, programme alarms went off, forcing Armstrong to consider aborting the landing and returning to orbit for retrieval by Columbia. And just 350 feet above the lunar surface, Armstrong realised Eagle's autopilot was guiding them towards a large boulder-filled crater. He overrode the computers and steered the craft downrange, risking running out of fuel and falling too fast to abort or being too high to safely crash-land.
But Nasa's worst fear - that Eagle's ascent engine might fail - was thankfully unfounded. If that had happened, Armstrong and Aldrin would have been hopelessly stranded on an alien world, condemned to run out of oxygen slowly. Collins, with no means of reaching his crewmates, would have had to make a terribly lonely return to Earth.
In fact, William Safire, former US President Richard Nixon's speech writer, prepared a short speech for the president to read out on television in case anything went wrong. "Fate has ordained that the men who went to the moon to explore in peace will stay on the moon to rest in peace," the speech ran, "… these two men are laying down their lives in mankind's most noble goal: the search for truth and understanding… Others will follow and surely find their way home. Man's search will not be denied." It was part of a memo, dated July 18, 1969, which outlined the following procedure: before the speech, the president would telephone each of the "widows-to-be".
After the speech, Nasa would end communications with Eagle as a priest performed the same rites used for a burial at sea, commending the bodies of the astronauts to "the deepest of the deep." Although it was never needed, the speech evokes a sense of wonder more than despair, and remains a fitting tribute to the astronauts who risked their lives in the name of discovery.
Prakash Chandra is a senior journalist
The views expressed by the author are personal