Wasn’t going to post anything today since it’s a bank holiday weekend here in the UK, but for him I’ll make an exception.
You might recall a couple of weeks ago I said astronauts didn’t need to be good pilots. Technically they don’t even need to be pilots at all since the entire flight system from take-off to landing is entirely automated. This is true for the vast, vast majority of astronauts since they only ever go on short trips up to LEO but there are a few exceptions, the most notable ones being the twenty-one Apollo astronauts, and especially Neil Armstrong.
That NASA landed men on the Moon using 1960s tech is something that astounds me every time I think about it. The level of computing power available on board an Apollo command module and lunar lander was several orders of magnitude lower than what’s contained inside your average smartphone, with 38 kb of ROM/RAM and a whopping 2 MHz of processing power. There are toasters on the market today with bigger computer brains than the Apollo lunar lander. In the Apollo Guidance Computer’s favour it was built from the ground up to handle guidance operations by some very clever people who squeezed every ounce of performance they could out of what they had available, but I still wouldn’t want to land on the moon backed up only by a toaster even if it is a custom-built one. If something goes horribly wrong and the computer makes a bad call you’re going to need to be able to fly the lander manually if you don’t want to end up as the first corpse to make it to the lunar surface.
Added to the paucity of computing power available was the uncertainty facing the Apollo crews in terms of where and how they were going to be landing the LM. It’s not like the return to Earth, where you just put yourself on a re-entry trajectory and plop down safely into the ocean; there’s no soft landing sites on the moon and no atmosphere to slow the landing craft down in an aerobraking maneuever, meaning that NASA and their contractors at Grumman responsible for building the LM had to come up with an entirely new and viable way of landing a spacecraft on another solar system body while keeping the crew alive and ensuring they could actually get back to the Earth afterwards. That’s a pretty tall order even if the thing you’re landing on has gravity only one-sixth that of Earth, and what they came up with was eventually immortalised as the Atari classic Lunar Lander. Go watch that video because it kind of emphasises why the lunar landers really needed a flat landing site.
The basic surface conditions of the Moon were known thanks to six Surveyor probes that had successfully made soft landings onto the surface, but that just told NASA what those six specific Surveyor landing sites were like. The landing site selected for Apollo 11 was the Sea of Tranquility, one of the darker lunar mare areas composed of volcanic basalt that was supposed to be relatively flat allowing for a reasonably safe descent and landing. What with the moon being the moon, though, a particular area of the moon being geologically flat at the time of its formation does not mean it’s going to be geologically flat today. The entirety of the moon is covered in craters and debris from asteroid impacts and the Sea of Tranquility is no exception.
So when the Apollo 11 guidance computer decided that the sloping, boulder-strewn face of one of these craters was a great place to land, Neil Armstrong and Buzz Aldrin had a very big problem. The lunar module needs a flat surface to land on. Those four landing struts are designed to support the weight of the LM but they’re not particularly robust. Wrecking the landing struts or – even worse – tipping the lunar module over on landing would have meant that Aldrin and Armstrong were dead men. The ascent stage on the LM used to get back into orbit kind of needs to be pointing straight up to do that properly. A bad landing would have made it a one-way trip even if they had survived. If the guidance computer continued to control the descent they were going to make a very bad landing.
I’m not saying other astronauts couldn’t have done what Armstrong did at this point. Probably all of the Apollo LM pilots could have, but Armstrong had an additional quality that helped him here: he was very slightly nuts and basically didn’t feel fear. The puff of smoke and flame in that video about a second before the training vehicle smashes into the ground is Armstrong ejecting from the LLRV. It was literally the last possible moment he could have ejected and survived, and all the while prior to that he’d been attempting to regain control of the vehicle. The best part about this is that the LLRV crash happened in the morning, and Armstrong was back in his office in the afternoon like nothing had ever happened. Thus when Armstrong took over from the guidance computer and attempted to land the LM semi-manually it’s no surprise that he pushed it very close to its absolute limit trying to find a safe landing spot; with Aldrin reading out velocity and altitude readings he finally touched down on the lunar surface with forty-five seconds of fuel left. They would have needed twenty seconds of fuel to perform an abort and get back up to the command module, so effectively they only had twenty-five seconds left1. The willingness of Armstrong to push things so close to the limit marks him out – marks all the Apollo astronauts and by extension the program out – as something almost unique in the history of spaceflight. Not in terms of what it did, because obviously nobody else has ever been to the moon, but in terms of what it symbolised and what it said about the country and the species that did it.
Spaceflight to LEO has almost become routine. While today’s astronauts are highly-trained individuals who are very good at their jobs there is nothing particularly remarkable about them, and aside from the risks inherent in all spaceflight endeavours they’re never going to have to take the great leap into the unknown the Apollo astronauts did. There might be an Armstrong somewhere in the modern astronaut corps, but if there is they’ll never get the chance to display their outstanding qualities; even though technology today is incomparably more advanced than it was forty years ago NASA is a shadow of its former self, having been bled dry by successive governments more concerned with short-term political gains than they are long-term vision. It’s not that spaceflight no longer needs men like Armstrong, it’s that the world lost interest in spaceflight a long time ago. They simply don’t want him. Keep that in mind when you hear the honeyed words of politicians desperate to somehow capitalise on his death:
“When Neil stepped foot on the surface of the moon for the first time, he delivered a moment of human achievement that will never be forgotten,” [Obama] added.
And if his administration has its way it’ll never be repeated, either. This Saturday didn’t just mark the passing of one man, it signalled the beginning of the end for the vision of manned spaceflight beyond our own Earth orbit. Just as Armstrong’s lunar landing symbolised something important, so too does his death four decades later with no attempt to repeat his achievement. He leaves the world a smaller, meaner place; a world where ambitious goals and the human tendency to reach beyond our grasp are no longer tolerated2. His death should be mourned for that just as much as anything else.
- Not that Armstrong would ever have aborted the descent under any circumstances short of total system failure, of course.
- Unless you work in investment banking.