"Refugee papers" OMG I'm dying here...

Biosphere 2 was an attempt at fully closed loop self-regulation. That doesn't work, and is not what is under discussion. The discussion is of using systems to maintain environments.

Production of oxygen is not remotely difficult. Not by plants, but again, industrial systems. Systems to make O2 from CO2 and/or water are TRL10. They exist, you can just buy them off the shelf. Same with reusable CO2 scrubbers (it's a very simple chemical process: cool = absorb CO2, hot = release CO2; they just cycle between cold and hot and whether they're connected to the input or output)..

You seem to have the idea that the proposal is just to have plants and humans life in harmony with no technology. If that were the actual proposal, I would agree with you. But that's not the actual proposal.

Yeah. Because if Mars' gravity is insufficient, and you'd have to live in rotating habitats anyways, then what are you even doing there, instead of being located e.g. on an asteroid where it's much easier to make a rotating habitat, where your surface is much more resource-rich, and where delivery and return of goods is much easier?

Venus, by contrast, I think few people doubt that its gravity would be sufficient for human life. Mars, it's *probably* enough, but it's not well studied. Moon seems like a coin toss at this point.

It's not entirely clear, but it's quite possible, arguably probable, that at least part of Venus's highlands involve fragments of ancient crust (the highlands also have milder conditions for exploration). Venus was Earthlike before Earth was, with vast warm oceans. There's also some arguments for life in the atmosphere based on gases that have been found, although I don't buy them (in the same way that I don't buy the same arguments for current surface life on Mars).

Don't be mad because you didn't see it.

Also, don't call them "editors"

And their hair is amazing.

I'm not saying that they can't do it, it's that they can't legally do it.

Ugh. Acrobat actually craps itself on forms now. The check boxes keep disappearing during scrolling, and I have the latest reader.

"The amount of raw materials used is significantly higher meaning the ecological impact is greater."

It isn't and that's also not how it works

No they did not. This story is about how they didn't. Learn to read, coward.

This isn't about a trademark. It's about a patented specification.

This is true. And the Republicans are the party of Nazis.

It's also a way to get around the prohibition on setting different prices for SNAP recipients. For example you can buy over the net from Costco with SNAP on Instacart but not directly. And the prices are higher there than on their site.

No. This is nonsense. Nuclear fuel production has a massive ecological impact. Nuclear only looks good when compared to coal. Stop doing that.

That's IMHO really overplaying it. I don't want to downplay food production effort difficulty, but saying "because we've never done it we can't" is like saying "Because we've never built a 5-meter-tall statue of a puffin made of glued-together Elvis dolls, we can't". We absolutely can, it's just a question of whether one thinks the investment is worth it. And I'm not talking out my arse, I have a degree in horticulture with a specialty in greenhouse cultivation. So much of the "keep the plants alive" systems we already do on Earth - you just need to get them there in an affordable manner.

The primary consumables are water and fertilizer. Nobody seriously is proposing building a colony that can't produce its own water. As for fertilizer, that would start off as an import, but a much smaller import than the food mass. On Earth, open-loop fert systems are fairly common, but they're slowly losing ground to closed-loop where you just maintain the EC, filter the returning solution, and every now and then due a nutrient-level test on the solution and individually adjust whatever nutrient might be lacking vs. the others.

We can consume lots of growing medium, like disposable rock wool cubes and the like, but we can also not do that. For example, it's perfectly fine to grow plants in clean sand / fine gravel - just clean it and sterilize it between uses. Something like pumice is better, though it slowly breaks down between uses. But you don't have to use anything special.

If you do LED lights, you may get a decade or so out of them. You can reduce shipping mass for replacement by going with designs that let you replace just the light boards from them (Mechatronix has lights like this for example), no need to resend e.g. the heavy heat sink, etc.

There's a million random things you use or that can wear out, from cleaning solutions to solution pumps to climate computers and and on and on. But they're not a meaningful import-mass, at least compared to food. Really, the big thing is fert. But regenerating fertilizer from waste (plant waste, human waste) should not be - industrially - immensely complicated. For the metals, burn to oxides / hydroxides, dissolve in acid, fractionally crystallize. You'll always lose some from the system, but we're not talking large amounts. For nitrates, Haber-Bosch is nothing exotic to adapt, and you have easy feedstocks (mining is complex, sucking in gases isn't).