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I love that blog! I think that door post is a perfect example of why we won't learn anything useful on Antarctica:

> Most (but not all!) doors open inward. There is a huge amount of snowdrift during the winter, and if the doors opened outward, they would be impossible to open without a lot of digging. This could be a life safety issue if the building is occupied.

On a Mars there is no "inward" like there is in McMurdo because swinging doors only work between sections with equalized pressure. Going outside requires an airlock that slowly normalizes the pressure to avoid shooting the colonist out the door with a blast of air. Going between sections requires doors that can slam shut in either direction to seal away damaged sections in case of emergency, like the sliding doors in almost every scifi movie/series/book - which we still haven't tested in the real world because there's nowhere to test that kind of pressure differential on Earth and our space station technology is still based on Cold War submarine hatches.

> there's nowhere to test that kind of pressure differential on Earth

This is patently false. NASA has a 100 x 120 foot cross section vacuum chamber at Plum Brook.

I'd expect such vacuum chambers to be relatively easy to build. The hull only has to hold one atmosphere of pressure difference, and it's pushing inward, so existing pressure tanks should be more than adequate with at most slight modifications. Generating the vacuum is mostly handling the sheer volume of air to evacuate because the quality of vacuum is irrelevant -- leaving 1% of air is as good as 0.001% of air when you are pushing doors against that pressure.

I mean in the context of actual use by humans in the day to day operation of a colony or other off-world facility.

There's obviously plenty of large vacuum chambers than can fit a door mechanism or even a small test room (the ones JPL uses to test spacecraft thermals was the first to come to mind for me, didn't know about the Plum Brook facility).

> The reason why is because you will learn a lot more by doing that stuff

But wouldn't 95% of that "stuff" be the same as doing it on the moon.

Which is closer, cheaper etc.

There are a couple (…um yeah…) of things different between Moon and Mars: lunar day is about 2 weeks long, which basically rules out solar-only colonies and lack of any sort of atmosphere makes radiation a significantly worse problem (not that it isn’t one on Mars…)

The Martian atmosphere provides almost no protection against the heavy ion component of galactic cosmic radiation, which is the dangerous stuff. The Moon more than makes up for its lack of atmosphere by being deeper inside the Sun's magnetic field than Mars.

The lack of atmosphere also means a risk of micrometeoroid strike on the surface & makes thermal control harder.

But for some industries this could be a benefit & even if the lunar dust is abrasive, at least it won't move itself that much without wind (though there could apparently be some electrostatic effects in play sometimes).

Also can't do aerobraking/aerocapture, but there is Earth next door for that.

> […] how to build a self-sustaining colony anywhere inhospitable first because it's never been done before, and all previous attempts have failed.

Hmm? It’s been done lots of times: it’s just that once people start living somewhere, we stop calling it “inhospitable.” But c.f. the Inuit, who’ve been living above the Arctic Circle for more than a thousand years.

But we... have already mostly done that in Antarctica already. There's not a lot more to learn by moving a few thousand more people to a particularly unpleasant place to live.

Is Antarctica self-sustaining?

No, but there's also little we gain from trying to make it so. We know how to operate all sorts of things in Antarctica, and anything else we bring there just... needs to be operated pretty much the same way.

Finding out we can't, yet, would be pretty important.

That's the wrong approach, though. "We can't" is the default state. The thing we need to find out is how to make it so. The goal is to be able to say, after all the finding out, that yes, we can now.

Not dying just because we can't, yet, would be pretty important.

But scale does add difference as does all the complexity required to make that scale self-sustaining.

That's not even remotely true. For one, we have barely scratched the surface of the psychology of living in an Antarctic outpost, and already what we've seen doesn't suggest long-term viability (decades instead of months). Perhaps with more people, the problems could go away, perhaps not - there's no reason to find out on Mars.