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Comment by XorNot | Hacker News Reader

I wonder what the expense of scaling this would be. Could you blow up a large inflatable greenhouse on the side of the station, for example, to get more growing area. Could you scale to reduce oxygen-demand this way?

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My first thought in the case of an inflatable greenhouse is that any small piece of debris is going to go straight through it. Not really a very knowledgeable area for me though.

Maybe we could use similar techniques we use for car tires to auto-close holes in them? Like two layers of outer surface and some chemical in between that would react with the air that's rushing out and seal off the hole? I don't know the details about such technologies, but it seems to me that inflatables should be much easier to make self-fixing than hard structures.

NASA has explored inflatable modules; they used a series of outer layers to reduce the energy of the debris, plus an inner layer made out of Kevlar.

http://spaceflight.nasa.gov/history/station/transhab/

The layers would have to be transparent, which greatly increases the difficulty of the challenge. Unless, of course, the plants were grown using artificial light rather than natural light. In that case you wouldn't need a greenhouse at all, but instead a wall of solar panels to power the added utility demand.

In the Ben Bova Mars series they have strategically positioned piles of patches that get sucked up and stuck in the holes. Maybe you could accomplish something similar with a middle layer that was oversized and stuffed in between the outer edges...

Inflatable habitats are certainly a thing[1] and there'll be one attached to the side of the ISS soon[2]. However you need a bunch of layers of touch material to make a spaceworthy container that won't get punctured by a meteorite and that means light doesn't get let in so you need to light them. Shifting the spectrum of the light to something that chlorophyll absorbs best might make up for the solar panel to LED inefficiency somewhat.

[1]https://en.wikipedia.org/wiki/Bigelow_Aerospace

[2]https://en.wikipedia.org/wiki/Bigelow_Expandable_Activity_Mo...

Are there any nutritious vegetables that can grow at high altitudes? You could keep the greenhouse at a lower pressure.

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