Magnetic fields aren’t going to stop gamma radiation, its just high energy photons. Electrically neutral. Most likely our atmosphere is stopping the gammas.
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You’re thinking of cosmic rays, which are, indeed, a concern for space dwellers, and can be screened out by magnetic fields, as can some radiation from solar events, which are the other source to be guarded against. There are different kinds of radiation hazard, which require different materials and methods to deal with. But all of them can be ameliorated to a great extent by mass. Even water will block gamma rays, if you have a lot of it.
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Defence in depth, maybe: carbon in the outer shell plus lots of water (which you’ll need for other purposes anyway) to stop ions and neutrons; metals (a thin layer of lead/bismuth as an outer layer to this, maybe? - dunno how feasible) and rock inside that to stop gamma and act as a substrate for soil; possibly an artificial ionosphere surrounding the vessel (magnetic field and argon ions or the like).
We’re sort of in the position of Roebling designing the Brooklyn Bridge - we ain’t really done this before, we don’t know what we don’t know, so we overbuild the piss out of it.
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But yeah, getting meaningful number of peeps off the planet isn’t doable without a space elevator. Even then, I seem to recall it wouldn’t keep up with population growth.
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This sounds like a great idea, as long as we make sure to keep at least a few of the telephone sanitizers here on Earth.
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Engineering issues aside, most people tend to underestimate the biological hurdles for a self-sustaining space colony. We haven’t yet come close to getting a “biosphere”-style closed ecosystem working on Earth, let alone space.
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Radiation! Yes indeed. You hear the most outrageous lies about it. Half-baked gogglebox do-gooders telling everybody it’s bad for you–pernicious nonsense! Everybody could stand a hundred chest X-rays a year!
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Except it’s the title of the podcast episode referred to in the post.[quote=“pesco, post:1, topic:80830”]
The fantastic podcast 99% Invisible told O’Neill’s story in an episode titled “Home on Lagrange”:
[/quote]
The only way I can imagine this making a difference other than for space tourism is if it were some kind of lifeboat for a doomed earth, in order to preserve humanity. Even then, I can’t think of a scenario when it could actually be used. While those making these claims sometimes have impressive academic backgrounds, the idea that it would help the environment and that it’s technically feasible make me wonder whether they ever got past the greenlighting stage. There are no resources in these places, so everything would have to be shipped to the cylinders (even if you could grow food later). Where’s the benefit over sending 5 billion people to a desert or underground on earth?
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Of course the original idea is that the economic justification for these was going to be the construction of solar power satellites to beam power down to earth. First there was the difficulty of beaming the power back down to earth. What are the ecological consequences and could that be turned into a weapon? But in a larger sense, there’s no real reason to build such huge, luxurious stations for the construction crews and maintainers of an armada of power satellites. We don’t build luxurious floating cities for for floating oil rigs and fishermen. Instead, it is cheaper to pay people extra to live for relatively short periods of time in extreme privation. If we discover an economic reason that we need large numbers of people in orbit, it is likely that that is what we’ll do with them too…
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Basically the plot of Seveneves, but with better amenities.
https://www.amazon.com/Seveneves-Neal-Stephenson/dp/0062334514/ref=sr_1_1?ie=UTF8&qid=1467480531&sr=8-1&keywords=seveneves
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LaGrange Point 5, a spot where the gravitational forces enable objects to just hang there
…just hanging there as it orbits the Earth one a month with the Moon and all the other L points.
O’Neill was one of the commencement speakers at my college graduation in the 70s. The fact that I remember his speech vividly, and don’t even remember who the other speakers were, says something about the man.
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OK, this reminds me of a central plothole from Interstellar that still pisses me off.
So the central plan hinged around unlocking the secret of manipulating gravity, allowing humanity to evacuate the surface of the Earth before “the Blight” made it uninhabitable. But if humanity had the technology to build self-sustaining space stations then they could have simply remained on Earth inside hermetically-sealed biospheres, making evacuation of the planet unnecessary. Way to overthink the problem, NASA!
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Yeah this plot hole applies to Silent Running too. In a similar vein, NASA in Interstellar has single stage to orbit landers which can fly deep into the gravitational field of a black hole, land on a planet with 1.3 times the surface gravity of Earth, return to orbit, then fly away from the black hole. So why is the manipulation of gravity and time so important to the establishment of habitats away from Earth?
I know that this problem was hand waved away in the movie by using conveniently located neutron stars to slingshot the lander towards the black hole, but thats one of those “nice in theory” ideas.
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I would love to know how it was possible to tow Amalthea into low Earth orbit, but virtually impossible to do the same with a water rich body. You’d think that a source of volatiles in LEO would have been identified as a priority well before the start of the book. As was pointed out it makes little sense to ship all these people into LEO while giving them nothing to drink or breathe.
Presumably there was a high ISP drive available for pushing asteroids around, so why wasn’t it used at the outset to either push the ISS into a higher orbit, or bring down more water?
Right, just like how …
… it turns out solar power stations work perfectly well when you build them on the ground.
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Cool paintings and stuff, but there’s this guy who is actually working towards colonizing worlds right now, and he’s succeeding. Like successful launches into orbit succeeding, with plans to go much further. You should write an article about him…
orbits the sun, not earth
I don’t think there is a difference for Earth-Moon, but there may be an advantage to using Sun-Earth L5, which is heading towards the Earth’s current position, over L4, which is heading away.
I am not an astronomer, so feel free to correct me if I’m wrong.
