I don’t understand why this argument gets made particularly concerning space exploration. Somehow it’s ok for humans to spend hundreds of billions of dollars per year on each one of entertaining movies, going on holidays, playing computer games, sports events, etc but a few tens of billions of dollars spent on space will imperil the long term survival of the human species and leave millions of people starving in Africa. That attitude seems crazily disproportionate.

Yeah, I'm aware of that. That's why I mentioned in the end that Musk is of course free to pursue his ambitions - in the grand scheme of things money is spent on much more pointless things, so him investing in science and space exploration is surely a comparatively good investment of his money.

I believe the innovations that come from such grand challenges such as becoming interplanetary will help solve other problems we face as well. I'm thinking of new materials, processes and technologies that can be applied in multiple contexts.

Places people don't want to live in:

- a submarine

- the middle of Death Valley

- the middle of Antarctica

- the (completely lifeless) top of mount Fuji

Living in a Mars colony would be a combination of all these experiences.

If you somehow have the magic sauce to make Mars enjoyable, you could offer this experience in the middle of the desert as well. You could tackle real habitation problems on this planet.

Just building a couple school buses (ISS) to float around the Earth took hundreds of billions.

And to the "what about nuclear war on Earth" argument: are you going to build a lightbulb factory on Mars? Semiconductor fab? Smelter? No Mars colony would be self sufficient for a realllllly long time

EDIT: Earth 2 Earth is interesting, though I don't know how you solve the vomit problem. Or the "sometimes the rockets explode " problem.

>Just building a couple school buses (ISS) to float around the Earth took hundreds of billions.

Absolutely, but then just one of these things will dwarf the ISS all on it's own. The old equations of space exploration affordability are being rewritten.

As for people wanting to go, there's a permanent base at the south pole, the peak of Mount Fuji is often a churned up field of mud from all the visitors and Burning Man looks like a ton of fun. Ok so some of that is frivolous. I'm ambivalent about the idea of Martian cities in the next 30 years say, but who can really look further ahead than that?

There's nothing that seems un-achievable about BFR. It seems to me these things will be going to space, and the Moon, and Mars at a ludicrously low cost compared to previous space missions. The real question is what will we do with that capability? I'm guessing we are going to do something with it. Musk's graphics are explicitly aspirational, but we'll do something with these vehicles and its going to be a heck of a lot more than any other plans I've ever seen.

Do you think the billionaires in their RVs at Burning Man would be willing to spend 6 months in that condition?

Even at a "ridiculously low" price of $500k, you're basically offering a mount Everest experience for people. Dangerous , uncomfortable, generally hard to do if you're not super free. A crazy adventure

Some people are interested, but you can't argue much for economy of scales when the total market of affordability is probably tiny.

Only 5000 people have ever climbed Mt Everest.

You are also ignoring the pioneer spirit. Don't forget that essentially built America. Imagine if no-one wanted to cross the Atlantic because it was too expensive or it was 'unsettled'?

People want to go to Mars. People want to try and live there. Scientists want to go there and learn, and explore.

Well, America had something going for it, especially when reports came back from the early explorers that it's lush and habitable (in many areas at least).

On the other hand, people know what to expect from the rock that is Mars. If Mars was an unknown and people would want to go there to discover what's there, then the analogy would be correct.

Of course, people will still go, but reaching a critical mass for an unnecessary settlement (at which point it might turn slightly more alluring for more immigrants) remains to be seen. But I guess what happens happens, we'll see.

I think you underestimate how quickly Mars could become an industrial powerhouse. It won't be starting at a Mayflower level of technology.

Why would it? It has less usable resources than loads of places on Earth that aren't used at all.

Maybe if Mars is some sort of lawless territory it can become the libertarian haven some rich people want, and could trick some future slaves to get sent over there....

It still has enough available resources (that we know of) to do well. And getting people to emigrate won't be an issue at all. Think of it like nuclear technology; developing an atomic bomb isn't difficult at all since the physics has been done 70+ years ago. Now it's just a matter of engineering. Same with building up an infrastructure on Mars. Somethings like large foundries probably won't need to be replicated, since 3d printing will probably suffice, but off the top of my head, I can't think of any technology that is out of reach.

We may always face existential risks. We now know of some concerning the next 50-100 years, but in 100 years we may know of different ones. Planetary redundancy conceivably aids our chances with those risks as well, so is a project best begun now, whatever the lead time. I don't want us always just solving the present crisis. We should think about the distant future too.

If you ask me, focusing on colonizing planets is the completely wrong long term survival strategy anyway. What would be much better would be finding a way to survive in space, just orbiting a star in some kind of craft. I mean, if you can't grow food on it anyway than a planet is just a really big asteroid with an unreasonably large gravity well to deal with. If and when we eventually work out a way to viably travel interstellar distances (my money is on ditching biological bodies), every star would be a viable colonization target.

There is the possibility of growing crops in Martian soil. [1] Nevertheless many agree with your conclusion that stations in deep space offer decisive advantages in their low-energy access to asteroid resources. [2]

Regardless of which path we take, the immediate technological prerequisite is the same: an economical way to send Earth payloads to space, i.e. a fully and rapidly reusable heavy-lift launch vehicle. That's what SpaceX is developing.

[1] https://phys.org/news/2016-06-dutch-crops-grown-mars-soil.ht... [2] https://en.wikipedia.org/wiki/O%27Neill_cylinder

Maybe you're right, but I'm thinking more along the lines of "autonomous life outside of earth is impossible in the foreseeable future, so optimizing for existential crises that threaten life on earth is pointless". The only thing we can avoid is that we ourselves destroy earth. Basically, if an asteroid hits us or something it's over anyway.

I think you may be overestimating the lead time to establish a self-sustaining colony. With the will, resources, expertise, and some luck, I think it could theoretically be done inside of 40 years. More likely it'll take quite a bit longer. But we don't need to be talking centuries.

> we do not have enough time to become multiplanetary anyway (since that will take centuries, and we will likely never leave the solar system anyway).

Neither of these statements are true. It's only a question of money, and money spent appropriately. Musk is demonstrating both of these.

As soon as we have a self-sustaining base on Mars, we're multi-planetary. There have been enough experiments to show that a man-made self-sustaining bio-sphere is possible. If Musk's timeline happens, this could be easily within a century, if not decades. To quote a phrase, 'necessity is the mother of invention'. It's likely that settling on Mars will drive the science and research that will solve these problems.

As for interstellar travel, that's well documented elsewhere on the web. It's doable, now, with current technology, without humans, but is massively expensive. And we don't know where to go. Once we do, it's just an engineering challenge for Musk V2 to solve.

One thing Musk didn't mention (I don't know why) is that the BFR would make asteroid mining and outer-space manufacturing far more practical, and that could help save the environment.

It's easier to colonize Mars than make life on Earth sustainable, because it involves convincing fewer people.