Mine crafts

I recently did a Twitter thread having a bit of a go at Aaron Bastani’s forthcoming book, Fully Automated Luxury Communism: A Manifesto,

Because it was Twitter thread I mainly poked fun, rather than look in depth at any of the futurology he was spouting. Some of it seemed iffy – his proof that “information wants to be free”, which is a cornerstone of his argument, is the growth, and reduction of price, in hard-disk storage and the ever increasing speed of Internet connections, for example.

bastani interview
“One day soon, love, hard-disks will be so large, and so cheap, that all intellectual property laws will just vanish. A real scientist told me that.”

Really, though, it was space I wanted to talk about.

I’m no expert. Hell, I’ve never even been there, but I am interested in it, and his argument that we could end scarcity of materials by mining Near-Earth Objects (NEOs) seemed to need a bit of work.

Bastani waffles on about rockets getting cheaper, 3D printing of rockets, private companies trialling their own rockets, etc., as if making rockets cheaper or reusable makes everything else about getting into space a technicality.

It doesn’t of course. Space isn’t very far away (if you live in, say, London then space is closer to you than Birmingham is), but it takes a huge amount of energy to lift off from our planet and, so far, we don’t have a better way of doing it than burning massive amounts of rocket fuel.

The reason that the fuel costs are so high is a bit like Zeno’s paradox of the tortoise, where Achilles can never overtake a tortoise in a race, because by the time he has run to where the tortoise was it has moved on a little further, and when he’s run to there the tortoise has moved further still, and so on.

So it is with rockets. If we want to launch a payload into space then we need a certain amount of fuel, but then we need extra fuel – to lift the fuel that we need to lift the payload. The we need more fuel, to lift the fuel that we need to lift the fuel that we need to lift the payload, and so on. This is called the tyranny of the rocket equation and, more than anything else, is why we haven’t found a cheap way to get into space yet.

To give you an idea of just how big a difficulty this is; if we were planning a mission to Mars, more than 30 million miles away (at its closest), then half of the fuel costs would be getting out of Earth’s gravity, less than 0.01% of the trip.

There are other ways to get there, in principle at least, ranging from the sane, but not yet possible (such as space elevators, which would work wonderfully, if we had an unbreakable rope, long enough to reach the Earth from a geostationary orbit – 26,000 miles up) to the downright crazy sounding (detonate a nuclear bomb, and ride the shockwave into space). Some of these may come to fruition but, for the moment, we’re stuck with burning lots and lots of fuel…which fits poorly with the heavily green policies in the rest of Bastani’s book.

Then you hit the problem that real space, and real physics, don’t work like science-fiction does. You can’t just point your rocket at a NEO, fire up the thrusters and fly there. Well, you can, but then you arrive at it way too fast and either sail straight by it and off into the darkness, or you crash into it at insanely high speeds, destroying all of the stuff that you wanted to send there in the first place.

Nor can you take up enough fuel to slow you down, because of the rocket equation, so you have to take an indirect path to your NEO. The lander, Philae, which touched down on a NEO in November 2014, took 10 years to reach its destination…and then didn’t deploy its landing anchors correctly, rolled into a patch of permanent shade and powered down forever.

Philae was one relatively small lander. To set up a full automated luxury mining operation on a NEO we’d be looking at multiple, much larger, craft, with each one being a roll of the dice as to whether it successfully reached its target, landed in the right place, or just smashed into all of the previous stuff you’d sent up, setting the project back to square one. The long lead-times, high start-up costs and enormous risks make this project even shakier than Labour Live.

Assuming we did get tonnes of autonomous, or semi-autonomous, machinery landed; drilling equipment, solar cells, processing equipment and got it all linked up and working, then what?

Let’s say it digs up 500 tonnes of iron ore, what does it do with it? Launching something from the micro-gravity of a NEO is much cheaper than launching something from Earth, but, again, we can’t just point our payload in the direction of the Earth and fire the rockets.

Anything heading towards Earth is accelerated by Earth’s gravity-well to escape velocity, which is around 30 times the speed of sound. A 500 tonne lump of iron ore hitting the Earth at that speed would impart the energy of a nuclear bomb exploding.

dinosaurs
“I told you it was a mistake to put the Bastaniosaurus in charge”

Incoming space-craft have heat-shields, to use the atmosphere as a brake, slowing them enough to deploy parachutes, so that they can splash-down at non-lethal speeds and be recovered. Potentially, our mining operation could have a supply of enormous heat-shields and parachutes, but we’re talking about a situation where an error made by an autonomous system, millions of miles away could see the equivalent of a nuclear strike at a random location anywhere on Earth.

Or, in theory, we could have a fuel-producing station on, say, the Moon. Mining water-ice and using solar power to split it into hydrogen and oxygen, to use as fuel. It’s conceivable that our incoming lump of iron ore could be intercepted, slowed down and dropped more gently into the Earth’s atmosphere…where it would sink to the bottom of the ocean, because iron ore doesn’t float.

That would also still leave the possibility of a lump of iron ore not being intercepted properly, which would put the whole world back on Russian-Roulette alert, or of it being intercepted and then something going wrong, potentially seeing the Earth being hit at high velocity by 500 tonnes of iron, loaded up with huge quantities of liquid hydrogen and oxygen.

These may be one-in-a-million risks, but to match current, Earthbound, iron ore extraction rates we’d have to receive more than 65,000,000 of these 500 tonne packages every year.

None of these problems are insurmountable, Mankind has proved itself to be an ingenious species, and off-world mining is almost certainly going to be essential if we’re to expand our species off Earth, and onto other planets, but the post-scarcity world isn’t imminent…no matter how cheap rockets get.

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