[acdha]

Multiple countries have bases in Antarctica, so it seems unlikely that a spacecraft-sized addition to the 50 acre McMurdo station is the proverbial straw on the camel’s back for a continent’s environment. Reusing human waste shouldn’t be a problem, either, since the proposals are to use that as fertilizer - it’s awfully expensive not to use everything that you shipped between planets!

And, yes, I linked to a best-selling popular science book at the level of the conversation here. I should note that the book has two authors, and the first one isn’t the illustrator but the professional biologist. You’re welcome to provide dissenting views if you want, I’m sure they wouldn’t claim to be the last word on the topic.

[somenameforme]

It's far below the level of discussion here or anywhere where there is discussion with varying views. The reason is that the book is broken in near to every single argument it makes, often intentionally by relying on misleading arguments or assuming the lack of knowledge of the reader -- knowledge which, crucially, I'm fairly certain they themselves had or should have had with even cursory level research on the topic. In a forum with debate those arguments rapidly emerge.

So for instance, their very first effort is to try to 'debunk' the idea of having Mars as a sort of 'backup' to Earth by claiming that even in the case of a doomsday event Earth would still be far more hospitable than Mars. That statement is completely true but also completely irrelevant.

Take a typical doomsday event, an asteroid impact or a supervolcano. Both kill you the same way which isn't the initial event, but rather the sun ending up getting blotted out for years by mass debris/ash not only causing an extreme freeze across the planet, but also ending photosynthesis rapidly killing all plant life which starts a mass extinction on up the food chain to animals that ate those plants then animals that ate those animals and so on.

This is the sort of event that could easily completely kill off humanity, but it's not because it'd make Earth a worse place than Mars. Even at the climax of mass extinction, Earth would still be dramatically more hospitable than Mars. The reason it will be so deadly is because it's so different than the conditions to which we prepare for -- more people die in the desert of drowning than of thirst. An offworld colony in this case would help ensure humanity is perpetuated, Earth is recolonized, rescue survivors, ensure global order, and so on. In fact this is the case for most of all conceivable disasters.

I wanted to dig into more of their arguments but this is already fairly lengthy. If you mention what you found most compelling, I can offer the data (or, as in this case, logic) to the contrary.

[somenameforme]

Also, I failed to respond to the Antarctica thing. There are small scale greenhouses in Antarctica ensuring the hundreds of people wintering there each year retain access to nice fresh veggies and the like without any external inputs. [1] It's not exactly novel technology, nor difficult to scale.

[1] - https://www.polartrec.com/expeditions/antarctic-weather-stat...

[acdha]

Right, which is both well known and not the question at hand. The point remains that a closed loop hasn’t been demonstrated under much easier conditions on earth and therefore it’s clearly not the easy task the person I replied to described it as.

[somenameforme]

All travel in and out of Antarctica is cancelled during the ~7 months of winter. So all of that is being done without external inputs during that time frame. A permanent (or at least practically permanent) closed loop is probably not possible because of the countless treaties. It severely limits what can be built, which local resources can be utilized, and even what you can do with your own waste.

[gamblor956]

The Antarctic treaties allow for the development of greenhouses, etc., for scientific research purposes (in areas that have already been developed).

And scientists residing there have tried to make a closed-loop system for decades now. They haven't succeeded yet. It's a lot harder to do than fiction and Hollywood would have you believe. Importantly from the Martian colonization perspective: it's irrelevant that the scientists in Antarctic can't use local resources to build their closed loop, because that's part of proving the Martian concept, where there aren't any usable local resources.

[somenameforme]

You're going to need to cite that because to my knowledge there's been 0 efforts towards any sort of long term self sustainability on Antarctica. The most I know of are the efforts to reduce diesel consumption, but that's probably more gesturing towards this 'green' political stuff than any effort at self sustainability.

And saying there are no usable local resources on Mars is ignorant of basic plans - sunlight, regolith which can be processed, hydrated minerals, CO2, water, and more. In the longer term the other various minerals and metals will also be highly useful, but those I listed are valuable right off the bat and easily accessible.

[gamblor956]

Sample on long-term sustainability efforts in Antarctica: https://en.mercopress.com/2009/02/18/zero-emission-energy-se...

Mars has lots of resources. They're simply not usable with current technology without extreme amounts of energy.

Mars also gets significantly less sunlight than Earth (43%), so solar isn't going to solve the problem.

[acdha]

It’s done with at least two external inputs (air, water) and far more resource availability than a Mars mission would have. A long-term closed loop isn’t banned by treaties - McMurdo alone is like 50 acres and a hundred buildings, something the size of a plausible interplanetary mission at our current technology level is not going to dramatically exceed that footprint.

Again, I’m not saying it’s inconceivable that it could be done, only that it’s harder than the sales guy would have you believe.

[somenameforme]

Mars has more than sufficient resources to provide practically endless air and water as well.

Beyond that I think you're also on a red herring here. There's no plan for a long-term closed loop on Mars to begin with. In the distant future most likely, but complete self sustainability is not practical in short to mid term timeframes. That would require essentially duplicating absolutely all forms of industry on Mars which probably will happen but only in the very distant future. In the interim a Mars colony would be receiving regularly shipments from Earth, and those return trips would also enable colonists, who decide it's not for them, to also return to Earth.