Forty years ago a Saturn V rocket launched from Cape Canaveral carrying three guys. Four days later, July 20, 1969 two of those guys were standing on the moon.
Let's start from square one: how does one get to the moon? To begin get your crew and position them at the top of a 110 metre tower filled with cryogenically contained explosive fuels. This arrangement is colloquially called a "rocket". Ignite the fuel. With a force of 7,648,000 ft-lbs (34,020,000 Newtons) all 110 metres of rocket begins to move straight up. It moves slowly at first, but with constant acceleration the velocity builds over time.
The Saturn V rocket is built in stages. When the bottom-most stage burns up all its fuel it falls off and the stage immediately above ignites. Through this trick the rocket continually gets lighter and thus requires less force to speed up. It accelerates faster. It's nice provided each stage ignites properly when the one below falls off. Otherwise the crew must abort the mission and head back down into the ocean.
Provided all the stages fire correctly without exploding the crew will reach Earth orbit. They are now officially in space. The first danger of being in space is of course the lack of air. The spacecraft is airtight and equipped with oxygen tanks and carbon-dioxide scrubbers. One hopes they still work after being violently shook by the initial launch.
The second danger of space is freezing. The temperature of space is just slightly above absolute zero, about -272 degrees Celsius. The spacecraft is equipped with heaters and insulation to keep the astronauts comfortable and, more importantly, alive.
The third danger of space is overheating. Despite the freezing temperature outside, the craft is in direct sunlight. This danger is especially present in cislunar transit, the three-day trip from Earth orbit to lunar orbit. The spacecraft will generate a dangerous temperature differential with one side baking in the sun and the other freezing in space. To avoid this the craft rotates slowly like a chicken on a spit for the duration of its trip.
Provided nothing's gone wrong the craft will reach lunar orbit thanks to a few course corrections and timed burns from the rocket engine. At this point the Apollo spacecraft splits in two: the command module stays in orbit with one unlucky astronaut missing the moon landing to babysit his craft. The other two move into the lunar module (LM) and have the honour of eventually standing on the moon provided they land the craft safely. Don't worry, they've practiced it before in simulators. Simulators built by people who have a fairly decent idea of what the lunar surface is like though they'd never been there themselves. In fact, until the moment Apollo 11's lander touched down no one was certain the surface would hold the craft's weight. Science fiction writer Arthur C. Clarke suggested in one short story that the lunar surface might be a powdery quicksand that would engulf the lander instantly. Scientists at NASA were not entirely certain this was not the case.
Then the glory: astronauts donning space suits and walking on the moon. Kicking up dust and leaving footprints, planting flags, putting on a TV show -- the usual activities.
After that it's a trip back to lunar orbit thanks to a final rocket booster on the lander. A historical note: all of the critical systems on the Apollo craft had a backup system or alternative procedures to avoid a failure except for the lander's booster. If it did not fire perfectly the astronauts would be marooned on the surface of the moon until their oxygen supply ran out and they suffocated. President Nixon had a speech prepared for this, thanking the brave American heroes who gave their lives. Thankfully he never had to use it.
After a final burn and three-day trip back to Earth orbit comes re-entry, a high speed ride through the Earth's atmosphere where the friction of the air heats the metal of the craft to glowing hot. Then, splashdown: the craft is dunked into the ocean and, hopefully, floats.
That's the basic outline of the Apollo 11 mission: the first moon landing. This entire mission, from conception, planning, design, implementation, and execution was done in eight years. In 1961 President Kennedy announced the goal of landing on the moon "within this decade." At the time of his landmark speech only a single American -- Alan Shepard -- had reached outer space, and Alan's flight was suborbital. President Kennedy pledged a pile of money but money can't buy you a spaceship that doesn't exist; a rocket that's only been dreamed.
NASA's rocketry team was led by Dr. Wernher von Braun, an ex-Nazi rocket scientist who spent his time during the second world war designing V-2 flying bombs. He was the real-life inspiration for Dr. Strangelove, though he was admittedly handsome and did not have a possessed prosthetic arm. The team also consisted of a bunch of other rocket scientists who'd worked mostly on military aircraft, flying bombs, and Earth-orbit satellites.
Much of the work was done by contracting companies, to varying degrees of quality. In the end the Apollo spacecraft consisted of 5.6 million "parts" organized into 1.5 million subsystems. All built on government contracts.
The astronauts chosen to pilot the Apollo craft, the most complex flying machine in existence, consisted of a bunch of pilots trained on aircraft whom NASA sent to a place that has no air. Later astronauts had varied backgrounds in science, geology, and in the case of astronaut Ed Mitchell, parapsychology.
There are many moon landing denialists who claim the whole mission is improbable and America never went to the moon. Moon landing deniers deserve to be shoved in the loony-bin beside holocaust deniers and people forging Nigerian birth certificates for President Obama. The calculations, plans, spacecraft specifications, diagrams, graphs, charts, and photos generated by the Apollo project are all in the public record and any individual is welcome to satisfy themselves with a glut of documentary evidence. It's shameful to the men and women who worked to make the project succeed and those who espouse that the effort was faked deserve the same treatment as documentary filmmaker Bart Sibrel who was solidly punched in the mouth by septuagenerian astronaut Buzz Aldrin. Go watch it on YouTube. I'll wait.
Perhaps the reason moon-landing denial exists is that the enterprise seems implausable in our age of individualism and self-improvement; of communication and information exchange. The idea that millions of subsystems could be developed and integrated in eight years without inter-team bickering sabotaging the product is alien to our free-market, profit-driven and litigious generation.
The Apollo program today would be labelled a disgusting pork-barrel project, too big for this age's slimming governments to propose let alone complete. This is not idle speculation: it was accusations of "wasting money" that finally killed the Apollo project, and the funds were shunted into anti-poverty programs whose names and effects have slipped from popular history.
Worse still the project would provide no profit. On paper, a man on the moon is worthless. In retrospect the creation of 400,000 jobs in the aerospace industry provided positive stimulus to the American economy, but in the eyes of traditional economics it was a huge money loser solidly in the red at forty billion US dollars, 235 billion 2009 US dollars adjusted for inflation. At least victory in the Vietnam war would have given America territory and reduced communist influence. Meagre gains but positive on the balance of power.
The moon landing was only achieved by a wave of nationalistic fervour. The project's primary goal was to beat the communists to the moon. To be first. Today, nationalism is considered almost universally distasteful. Our first thought when we hear the word is of Naziism, not interplanetary travel.
The technology to get to the moon is lost. Even if it was desirable to fire a Saturn V rocket to orbit there are none left in operating condition. Most are sitting in museums or rusting away in aerospace junkyards. The people who knew how to fire them are old if not dead. As a government agency NASA is only a crumb of what it once was in employees and funding. Yet more than the technological hurdles, the cultural climate of this age is not conducive to returning to the moon. The nationalism, the will, the enthusiasm is not present. The second President Bush announced a plan to travel to Mars but the cheering was heard only from self-professed "space buffs." The vast majority of first world citizens rolled their eyes and scrolled to the next article in their RSS readers. A few months the space buffs noted with frustration that the funding for the project was woefully inadequate.
It's not that we'll never set foot on the moon again: NASA is committed to returning to the moon, establishing a long-term presence there, and then setting their sights on Mars. They have a timetable and are developing whole new pieces of technology like the Ares-I solid booster rocket and the Orion spacecraft. The truth is, however, NASA has languished for a long time with inadequate funding. Space exploration is not a popular thing to pay for.
The existing Space Shuttle fleet is scheduled to be decommissioned in September of 2010 and the next generation spacecraft is nowhere near ready. As marvelous a piece of technology as the Space Shuttle is, NASA delivered it late and over-budget. It cannot escape Earth orbit, meaning it is hardly as capable as the Apollo craft except that it can carry a much larger payload and stay above the clouds a bit longer.
The space station is a wonderful bit of public relations in that it is an international effort, but it is unsophisticated and, some have argued, pointless. Maybe it's unreasonable to expect oxygen-producing orbital greenhouses and vegetable gardens, but these are what's needed to achieve a trip to Mars. The ISS will only have wastewater recycling and oxygen production support when the Tranquility module is launched in February of 2010. The ISS was supposed to be complete in 2003. It is currently projected to be complete in December of 2011. Its major contributions to science involve the aerobic capacity of astronauts on stationary bikes.
While NASA's progress has not been completely nil, one gets the feeling the forty years of work after Apollo 11 have been remarkably less fruitful than the mere eight years it took to get to the moon. More milquetoast than adventurous.
Yet it happened, once. A united, concentrated effort achieved in eight years a feat that even forty years later remains astounding. Can we do it again? If we can convince ourselves that the exploration of interplanetary bodies is truly worthwhile, that living beyond the Earth is a noble goal for the dissemination of the human species, then we can achieve massive gains in space vehicle technology without the threat of Cold War nuclear annihilation and anti-communist fervour. We can travel all over this solar system. As a culture, if we demand it we can get some work done and set some new footprints beside those stamped into the lunar soil over forty years ago.