That was done using freeware space simulator Orbiter, and I have to say, the dude Timm behind it sure knows his stuff. I downloaded Orbiter a week ago and wow, you basically have to know rocket science. Like music, the basics are not difficult to learn, but actually putting the specifics into practice will take a lot of, well, practice. In theory a low Earth orbit is just applied geometry – since gravity is a constant, X altitude just requires Y speed, right? In practice, working out exactly what Delta-V you'll need to circularise your orbit and therefore how much thrust for how many seconds to give you that Delta-V (and in which vector) will absolutely have you pulling your hair out. And don't even get me started on the complications if you get lazy and try anything without circularising your orbit first...
Ahem. Anyway, the Soviet moon landing. Highlights include:
0:00-1:27: Actually getting the N1 rocket to work. The N1 (from the Russian nossitel, or "carrier") was the Soviet equivalent of the Saturn V, except without the rockstar status, payload capacity, enviable reputation among cosmonauts or a single successful launch. The Soviet moon programme wasn't begun until 1965 – four years behind Apollo, and ten years behind the massive Rocketdyne F-1 engines that made Apollo possible. Without a heavy-lift engine of their own, the Soviets had to make do with lots of little ones instead. So in Block A, the N1's massive first stage, instead of five F-1s they had thirty NK-15s, designed to produce a single unified plume seventeen metres wide. On paper, the N1 was actually more powerful than the Saturn V.
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| I believe it. |
Unfortunately, the N1 never got to set any records, because four out of four test flights ended in catastrophe. Block A was too powerful to test as a unit, so every launch was affected by vibrations breaking stuff, vibrations that didn't show up when you tested each engine separately (if you could be bothered – only two engines from each batch of six were fired up before being installed on a spacecraft). And as any regular Mythbusters viewer could guess, getting them all to light at once was a bitch. The internal plumbing was like a 90's screensaver, trying desperately to get enough kerosene fuel and oxidiser to thirty engines at once, kerosene that was non-rocket grade and prone to coking (i.e. covering everything in soot).
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| Please note that the things dragging it out to the launch pad are freaking diesel trains. |
The net result was that no N1 launch even made it to first-stage separation. The most famous of these non-events was the second test (unmanned, they were all unmanned) on July 3, 1969 – only thirteen days before Apollo 11 was due to blast off. Just before liftoff, the liquid oxygen pump on engine #8 exploded, damaging the internals and creating multiple fuel leaks that triggered a secondary explosion just as the base cleared the tower. All the engines shut down automatically, as per safety precautions, all except #18 which remained lit throughout the flight (for reasons still unknown), causing the whole thing to lurch over like a skydiving sperm whale and drop back onto the pad. Whereupon it exploded, in a 5-kiloton blast, the largest non-nuclear explosion in history that was seen 35km away in Leninsk. Amazingly, only a tiny fraction of the onboard fuel actually burned – as little as 15% – and technicians on the pad half an hour later reported unburned fuel was still raining down. And thankfully, the escape tower did its job and got the crew compartment out of danger, so if there had been anyone on board they absolutely would have survived.
But of course none of that happens in the Orbiter video; this N1 actually flies. And it's a beautiful, beautiful thing, because although the N1 had feet of clay, the rest of it was actually pretty good.
2:29-3:10: Trans-Lunar Injection and the Three-Day Coast. Mostly glossed over in the video, but I want to turn a spotlight on it (I have Jeffrey Kluger's Lost Moon, the book that became Apollo 13, and the figures are really interesting). To become the first people to loft themselves out of Earth orbit, the crew of Apollo 8 had to initiate a prograde Delta-V of some 3,000m/s – or in English, they had to jam the throttles wide open and accelerate from the 28,000km/h needed for Earth orbit up to more than 40,000km/h – above 11km per second – to extend their orbit from a circle to a weird egg shape to a long, lassooing loop that encompassed the moon as well. Speeds like this were necessary because the second they shut down the engines, the Earth's gravity resumed tugging on them, bleeding off their speed like a car coasting uphill. For two days they steadily lost speed, dropping to 30,000km/h, then 15,000, until at the five-sixths distance the gravity of the home planet gave way to the Moon's where they were crawling along at barely over 3,000. With the moon's gravity pulling them in by the time they arrived on the dark side they'd have been up above 8,000km/h again, requiring a shortish four-minute burn to slow down and drop themselves into a nice, cosy lunar orbit. The Soviet machinery was a bit lighter than the Apollo versions, so the speeds could've been a bit lower, but overall they'd have been broadly similar.
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| For a closer look, check out Hamish Lindsay's Apollo 8 essay here. |
All this would've taken three days, which – I can't stress this enough – all would've been spent inside a Soyuz capsule. Soyuz was not Apollo's four-bedroom mansion, it was a quaint duplex only designed for Earth orbit. It was like going to the Moon in a modified Gemini capsule (which idea actually was tossed around for a while). If not for that spherical rumpus-room at the front, it wouldn't have been any more spacious than the Smart ForFour Richard Hammond and James May spent 24 hours in – only for more than a week instead of just one day, and without a backseat to climb into when nature called.
4:18-5:00: EVA over to the LK. Cliches should generally be avoided, but like the T-34 tank, the Soviet lunar vehicles were crude but effective. The Americans docked the Lunar and Command Modules together so the crews could shimmy from one to the other any time they liked. The Soviets decided this was for childrens and told their crews to suit up, roll down the window and bloody well spacewalk out of their capsule and over to the lunar lander.
I'll say that again: a spacewalk in lunar orbit. Imagine. The. View. The Apollo astronauts said it looked like you could just reach out and touch the Moon, and that was while fighting for viewing space at the cabin-cruiser porthole they gave you in the CSM. With nothing but a visor between you and your destination, the view would've been utterly gobsmacking. Consider how the moment would've lived in your memory if you were one of the lucky few. Then consider the inconvenience of spending the rest of your life with a regulation extra-large wheelbarrow, which is what you'd need to cart around your massive brazen balls in a 1g environment. Because in case you didn't know, space doesn't really feel like floating, it feels like falling, because that's exactly what it is. You're falling back towards the surface of the Moon like normal, it's just that you also happen to be moving sideways so fast that by the time you get to the ground it's not there anymore, but curving over the horizon, so you keep falling forever. So now imagine your inner ear screaming that it's time to pull that ripcord and looking down to see half a gazillion overlapping grey craters spread out beneath you? I can't comment on Soviet tech, but NASA didn't invent the jetpack until 1984, and I don't see any tethers in the video. And of course, you have to do it again on the way back too. And no offense, but the hand rails were installed by communists.
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| And scaled correctly the Earth-Moon distance looks like this. They were a long, long way from home. |
5:24-7:00: Descent of the LK. If Soyuz was a capsule, then the lander itself was more of a suppository. Called the LK for Lunniy Korabl, or "lunar ship," it was very much the poor man's LEM. It was only big enough for one cosmonaut, and the legs were just a sort of detachable guitar stand, using the same engine for ascent and descent. The advantage of the LEM's separate ascent and descent stages was that if something went wrong on the way down you could pull the abort handle, fire up the ascent engine and make a sharp exit: if a single thing went wrong with the single engine on the LK, that single cosmonaut was going to die. All the same, you just know Timm landed that bastard manually, because you would, wouldn't you?
Historically, a couple of LK's did fly, but only unmanned and only in Earth orbit – test missions launched by normal Proton rockets. More recently it's been given a cameo in 2011 film Apollo 18, which at least gives us a wonderfully realistic look rather than the unskinned model in Timm's video.
I haven't seen Apollo 18 in its entirety, but for what it's worth I don't recommend you do either. In theory a lunar mission offers plenty of material to the horror writer – sense of total isolation, staring unblinkingly at a hostile and uncaring the universe, etc, etc – so much potential! And what did Brian Miller give us? Aliens that look like rocks. I can't even.
12:13: A Hair-Raising High Speed Re-Entry. On the flight back to Earth, the speed equation works the same, but in reverse – it takes a very small rocket to get you away from the moon, but once big beautiful Earth gets ahold of you you're in for a wild ride. From a virtual standstill at the threshold, your velocity builds and builds, until you'd arrive back in the upper atmosphere with the same 40,000km/h you left with – about the same velocity as the Chelyabinsk meteor. And if you got the angle wrong you'd suffer the same fate as the Chelyabinsk – too steep and the G-force would crush the crew, use up the heat shield and probably break the ship up completely; too shallow and, as the movie of Apollo 13 was at pains to tell us, you ricochet off the atmosphere and never come back (except Apollo 13 would have come back, but that's another story). With 40,000km/h to wipe off in only 400km of atmosphere, the safe corridor between these two extremes is only 2.5 degrees wide.
For a final flourish, Timm brings it home by parachuting safely to a landing on actual land rather than an American-style splashdown: the Soviet Union had plenty of landmass so there was no incentive to put it down in an ocean somewhere. In Vostok 1 Yuri Gagarin actually had to bail out and parachute to the ground himself, a fact the Soviets tried to keep to themselves because Yuri had set a lot of records and the aviation rules said they only stood if you brought your craft down to a controlled landing. When they found out, the international community rewrote the rules so Yuri could keep his records.
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| A photo of the damn thing on the ground, in case you needed reminding how small it is. |
Annnd that's about it, that's more or less how it would've gone. So what if they'd actually done it? Would the Americans have moved the goalposts again? Would we have seen Nixon pledging a mission to Mars, to boos all-round like Bush? It's a nice thought. Unfortunately that was never going to happen. The Soviet moonshot was partly hamstrung by a 1965 starting gun – way too late to compete with Apollo, which had been in development since 1961 using off-the-shelf equipment that had been in development since 1955 – and partly hamstrung by the death of Sergei Korolev, the heart and soul of the whole Soviet space programme. His death (in 1966, of complications following surgery for cancer) quite took the wind out of Soyuz's sails, his successor Vasily Mishin having neither the political clout to keep the funding coming nor the technical skill to solve the myriad problems coming up. It was on his watch that the N1s went four-for-four, and in the end his only contribution to manned spaceflight was the Apollo-Soyuz Test Project – scientifically worthless, but politically priceless. The Buran shuttle aside, it says a lot that parts of the International Space Station were launched in Soyuz capsules.
I really hope next year's launch goes well. I got a taste of space-excitement with New Horizons; I'm more than ready to watch every minute of a Mars mission. Bring it on.
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