50 years ago, we flew to the moon. Here's why we can't do that today

Only seven years after U.S. President John F. Kennedy announced the U.S. would send humans to the moon within a decade, the mighty Saturn V, the largest machine to ever fly, rose majestically off the ground on November 9, 1967, on an unmanned test flight. Two years later, Kennedy's dream was fulfilled, with one small step on the lunar surface, in the greatest technical achievement in human history.

Now, half a century later, today's rockets struggle to accomplish the same task.  

The success of the Apollo Moon Program lay largely in a massive brute force effort, where the government funded roughly 400,000 people from across the entire U.S. to ensure the Americans beat the Russians to the moon. Considering they were building an enormous system that was entirely new from the ground up, on a ridiculously short timescale, it is amazing the rockets performed as well as they did.

True, there were two accidents — a fire on the launch pad of Apollo 1 that took the lives of three astronauts; and an exploding oxygen tank on Apollo 13 that crippled the mission, but those astronauts were able to return safely to the Earth thanks to even more teamwork.

All the numbers around the Saturn V rocket are astounding:

• Standing 36 storeys, twice as high as Niagara Falls.
• Weighing 2.8 million kilograms (6.2 million pounds).
• Producing 34.5 million newtons of thrust (7.5 million pounds) from its first-stage engines.

In all, NASA flew 13 Saturn V rockets, and all of them did their job of delivering 24 humans to the moon — with 12 of those humans walking on the surface — as well as lifting the first American space station, Skylab into Orbit.

Because of the tight timetable, the first flight, known as Apollo 4, was an "all up" test, where the entire rocket was flown with everything in place. This is risky, because the assorted parts of the rocket were built in different parts of the country and had never operated together as a single unit. Remarkably, the first flight was a total success.

The space race of the 1960s was a time when taking chances was the norm — chances that would never be taken today. Even though the second test flight of the rocket did have problems with huge vibrations, parts shaking loose and engines shutting down prematurely, it was decided that on its third time in space, there would be humans on board and they would go all the way to the moon.

Apollo 8 is often considered the most daring mission because it was the first time human beings left the gravitational pull of the Earth and committed themselves to another heavenly body. It was also the first time humanity saw itself as a single living entity with the famous "Earthrise" picture taken from the moon.

Never, in the history of technology has there been such inventiveness, innovation, daring, and remarkable achievements in such a short time as the moon missions. It is amazing what can be accomplished with virtually unlimited funds, an enormous workforce, and willingness to take huge risks. And of course those risks paid off when Neil Armstrong and Buzz Aldrin touched down on the moon for the first time … with only seconds of fuel remaining in the tanks.   

Of course, those conditions don't exist today. The NASA workforce is one-tenth of what it used to be and funds are limited. The last 45 years have been spent building space shuttles and the International Space Station, which is why we don't have the technology to take people back to the moon.

Another giant rocket that will rival the Saturn V, called the SLS, is under construction, which could take astronauts beyond the moon, possibly to Mars. But it is tremendously expensive and behind schedule, with its first flight now pushed back to 2020.

The other contender is the Falcon 9 Heavy, being built by the private corporation SpaceX. It is scheduled to fly within the next few months, but a recent test of new engines resulted in an explosion, and  the company's founder, billionaire Elon Musk, says there is a good chance the rocket will not make it on the first try.

Anyone who was around during the heady days of the moon program was convinced that half a century later we would be taking family holidays on the moon, setting off from an orbiting space hotel.

Oh, well.

It is unlikely there will be a time like that again.

Leaving the Earth is not easy, even with 50 years of experience. But that doesn't mean we should stop trying.