Taking your points out of order.
As you say.
This is one thing that baffles me about terraforming. The arguments for it quickly move in to tortured claims about what people might be able to adapt to. If we're terraforming, no adaptation should be required, never mind extreme (as in new species) adaptation.
Indeed, but terraforming is not a process that completes over night. It occurs over time, and people can and likely will become acclimatized to it as it continues. I used the 1/3 because the gravity is 1/3, presumably capable of holding onto an atmosphere 1/3rd the density in the same way as Earth holds onto the one here. It wasn't a stopping point, only a milestone.
The top of Everest doesn't have permanent encampments, never mind a civilization. The environment there routinely kills people who visit.
Indeed. That's sort of why I said "Not much farther". So, when the gas density on Mars gets to 1/3 torr, people can get by on respirators rather than pressure suits. Those people who cannot stand that then don't go out into it, just as they don't (or rather shouldn't) go up Everest.
I would start by pointing out that you're addressing one of the side effects of 1/3 G. The primary point is that 1/3 G isn't 1 G and can't be changed absent finding several more Mars size planets or equivalent and dropping them on Mars.
No Magnetic field. One more major way Mars can't be Earth.
What - Earth II or bust? Sort of strict, aren't you? I bet you live on sea level at 60 degrees F, right? These things are attainable, with current or slightly more advanced science/engineering. The absence of a magnetic field means that solar flares are more of a bother, but putting up an atmosphere will take care of most of that in the long run. You won't be able to use a compass.
Well, that's awfully glib isn't it? Do you think that liberating 200 trillion metric tons of oxygen is likely to be one of the things we'll learn during this crisis? And BTW 200 trillion tons of oxygen is just the obvious part. To get the pressure on Mars up to something Earth like we'll have to create even more of some other gases.
What, you have something against glib - it has to be possible today before you are willing to speculate a little about what will be possible in 100 or 200 years? You think things are simply going to come to a standstill on Earth, engineering-wise? I understand that at least one plan calls for releasing CO2 from the rocks about the planet to increase the pressure to where pressure suits wouldn't be required, and then letting plants do the rest - that's all within our current engineering capabilities (with a little more gene engineering for the plants, at least initially); indeed, we're trying to undo it on our planet here. Done just that way, it might take 100 years to get the pressure and temperature up and then 10,000 years to make it as oxygen rich as Earth, but there are more possibilities than that just over the horizon. The comets are another possibility, but that takes rather more engineering, and may not even be needed as water has been found on Mars in quantity.
I think I have to grant that if we can build the atmosphere in the first place we could sustain it, at least for a while. But it might be instructive to identify the energy source for this liberation process and to identify the reserves of whatever feedstock is feeding this process.
Well, don't be shy. I'm not a geologist, so I cannot help you out outside of what I read, so you perhaps have a better idea than I do. Perhaps there will be some huge roadblock and it won't be possible, like finding no bedrock where you want to plant the north tower of the Golden Gate, but that's not proven, and perhaps there will be a workaround. Want to bet on it?
What obstacle to continental sized space stations can you identify that isn't hugely worse in the case of terraforming Venus or Mars?
I have absolutely nothing against them. I'd love to see them. I like Arthur C Clarke's vision of a jewelled bracelet around Earth's equator at LEO, and G Harry Stine/Lee Corey's view of huge power stations at GEO absorbing rays and microwaving them to antennae on Earth. (I might point out, vis-a-vis your argument above against terraforming unless it generates a new Earth, that there is zero pressure and no magnetic field at GEO, and no way to fix either at all.) But mainly my question is, screw the problems, when are you gonna start?
I work at JPL, we do primarily uncrewed stuff, although my work supports both -- and I firmly believe the correct answer is "both."
