Is that what was meant? I didn't think of that -- normally the word means 60 years from now.

Yes, I'll be surprised if they manage a crewed mission at all by 2029.

Ok, we'll make it 2081. Still bullshit. There is absolutely no way that there will be a Mars based self sustaining colony in that time period. Real life and Hollywood are both able to surprise us but only one of those two dabbles in self sustaining Mars settlements for the foreseeable future.

When the moonlandings first happened the papers and popular science writers (and SF writers) were all over what would happen next. What happened next is nothing. Sure, we have the ISS, it's been a neat little testbed and good PR for space development.

But colonizing another planet is a lot harder than it may seem. I'll challenge anybody that believes that this can be done to 10 30 ton semis full of gear, food and oxygen, then to set up shop right off the coast somewhere and prove that within a decade they can be self sustaining. That's many orders of magnitude easier than doing the same thing on Mars and it is still very much this side of impossible.

The 'self sustaining' bit is the nasty part here, as long as you can ship in food, oxygen, water, toilet paper and whatever else you think you might need on your faraway planet you'll be fine within your little environmental cocoon. But another planet without a breathable atmosphere is so incredibly hostile to life that your first mistake will be your last.

If "absolutely no way" is everyday hyperbole for "I think it's unlikely" then sure, I think that's reasonable. It would need a break in current trends.

60 years is the interval between Zuse's first Turing-complete relay computer and the popping of the dotcom bubble. Or between the Wright flyer and Project Gemini. Outer space has ridiculously more resources available than Earth surface, making it economically irresistible. Powerful economics plus 60 years of development can equal... a lot, as I said to start this subthread. Mars itself is not very attractive, but if space happens bigtime then even a sideshow can also happen.

100% self-sustaining would be unlikely (there's no real point in the last increment towards that), but colonies on Earth always had trade too.

They had trade because they could. A Mars colony has to be self sustaining otherwise it will simply vanish at some point. For trade to work the cost to trade has to be acceptable.

Think of a world with many orders of magnitude more space travel, at an energy cost on the same order as the net energy difference between source and destination (which can be negative depending on net flow). Is that a world of autarkies? No, except where people prize autarky for its own sake.