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Looks like someone has lost all hope for humanity and at that we should just accept our "inevitable" self-destruction.

Even if the dream of colonizing mars is farfetched beyond fixing all of the problems we currently have on earth, it doesn't mean its not worth striving for. Goals like this drive people to do their best work and come up with creative solutions to problems that would otherwise never have been thought of. This is the exact kind of drive we need if we are to even have the chance at becoming interplanetary. Maybe we end up just getting to Mars and setting up an "antarctic" like lab that is occupied by teams for months at a time? That's fine. The innovation that got us even there would have been amazing. Maybe the goal then shifts to self-sustaining interplanetary spacecraft. Humanity isn't done yet, and not shooting for the far reaches of the galaxy is a waste of time that we cannot spare.

Musk Co. isn't just focused on that interplanetary goal. There's a lot that is also being done to make this planet better and prolong its life. These are honorable and not nearly as farfetched goals. Musk's drive to solve these problems is a real inspiration to many and may be our only chance in hell to pass through the Great Filters.

!Mars != !Space.

Mars is a dusty, barren deathtrap of a rock that's at the bottom of a very deep hole. The only thing to do on Mars is to _be_ on Mars. It's not (plausibly) terraformable, sustaining life there will obvious continuous and hugely expensive technical input, there are no resources there worth going there for, and once you've gone there, to get back you have to climb out of a hugely deep hole.

Meanwhile the solar system is full of places that are easier to get to, more hospitable, more profitable, and which you can get away from. Asteroids. Comets. Ceres. The moon, even. Further afield, the rings of Jupiter and Saturn --- the radiation's a bit rough, but if you can survive there, you've got it made. Hell, if you're into planets, Venus is a better option. Did you know that there are parts of Venus which are a shirt-sleeve (and breathing mask) environment?

Mars is fascinating, and there should absolutely be a science station there eventually, but it's not colonisation material. I certainly don't think it should be a priority right at this moment. With our current state of the art, I believe the Moon to be a much better choice.

> Did you know that there are parts of Venus which are a shirt-sleeve (and breathing mask) environment?

Nope, that's news to me. According to:

http://earthguide.ucsd.edu/eoc/special_topics/teach/sp_clima...

the minimum temperature on Venus is 870F, well above the melting point of lead. Do you know something that UCSD doesn't?

They aren't on the ground.

http://www.iflscience.com/space/nasa-wants-establish-floatin...

We're talking about colonization here, not exploration. That's not even a practical plan to make more living space here on earth, let alone on Venus.

It's actually not all that impractical. Venus' atmosphere is much more dense than Earth's; floating in it should be quite a bit easier.

> Venus' atmosphere is much more dense than Earth's

Won't help:

"The ships would float 50 kilometers (31 miles) above the planet’s surface. Here, there would be only one atmosphere of pressure, and the temperature would be a reasonable 75"C."

75 C is 160 F. Granted that's cool enough to keep water from boiling, but unless you're a tubeworm you're probably not going to be happy living there without air conditioning.

Considering the temperature fluctuations faced routinely even in Earth's own orbit, 75 degrees Celsius is actually very reasonable. It's certainly no less comfortable than Mars' rather frigid climate. If anything, the greater hazard would be the toxic and corrosive clouds of sulfuric acid that blanket the Venusian surface.

The density, however, more has to do with whether or not it's feasible to build a permanent settlement in Venus' atmosphere. It turns out that it's very feasible; Venus' carbon-dioxide-based atmosphere would be thick enough even at those altitudes to keep a "balloon" filled with an Earth-like atmosphere (nitrogen, oxygen, trace CO2) afloat with little effort. This means that such a ship or city wouldn't need separate balloon and living spaces; the living space itself would be buoyant.

You can handle extreme temperature fluctuations in Earth orbit because you can dump excess heat into space with radiators. That won't work inside a hot, dense CO2 atmosphere. Maybe there's some other solution to the cooling problem that I have overlooked, but I don't see any way to keep from turning into a sous-vide.

One such approach would be to use Sterling coolers, which (IIRC) is one of the suggested approaches for surface activities on Venus. Standard refrigeration techniques should also work reasonably well.

Also, why wouldn't standard heat-dumping work well in a CO2 atmosphere? If anything, it should work better; the vacuum of space is the best insulator known to man, so literally anything else would be better for heat dissipation.

> Sterling coolers

Doesn't matter what technology you use, you are still bound by the second law of thermodynamics. The excess heat has to go somewhere, and so unless you have a cold sink, you have to add energy. And if you're going to colonize rather than just explore then you have to add energy all the time forever. If the power fails, you die, she dies, everybody dies.

> why wouldn't standard heat-dumping work well in a CO2 atmosphere

That depends on what you mean by "standard heat dumping". In space, you can radiate heat into the cosmic background radiation, which is the ultimate cold sink. It's about 3K, which is almost always colder than you want to be [1], so in space you get cooling for free.

If you're inside a dense atmosphere, radiative cooling doesn't work. (There's a reason they're called "greenhouse gasses"). You have to dump the heat into the environment, which is hotter than the temperature you want to maintain, so you're fighting the second law, so you have to add energy. At the altitudes we're talking about here, you're maintaining a gradient of 30-40C. That's huge. It's not impossible (the artificial ski slope in Dubai maintains a similar gradient) but it takes a tremendous amount of energy. Where are you going to get it?

---

[1] There are some cases where you need active cooling in space, for example, if you're running an infrared sensor on a telescope. Those have to be actively cooled, usually with a supply of liquid helium that is launched with the spacecraft. But see:

http://jwst.nasa.gov/sunshield.html

for an example of what has to be done to keep an infrared telescope cool for a long mission.

"Did you know that there are parts of Venus which are a shirt-sleeve (and breathing mask) environment?"

Please expand on this.

Venus has a very thick atmosphere. At the height of a few miles above surface, there are layers with room temperature and human-acceptable pressure. Of course, the atmosphere is still CO₂ with some nasties, so a gas mask is required. But a Star-Wars-esque floating city would be quite manageable there. You can use hydrogen for floating because there's not oxygen around, so no risk of a blast.

NASA is already working on it: http://www.cnet.com/news/nasa-wants-to-build-a-floating-city...

50km up, actually. (Venus' atmosphere is scary thick.)

And it's better than you think: the atmosphere there is largely carbon dioxide, which is denser than air; so you don't need hydrogen for bouyancy. You can use breathable air and live inside the balloons. The inside's at a slight overpressure, so any leakage will be outwards rather than inwards, and the pressure differential's pretty small so it's likely to be pretty unexciting.

You're above the clouds, so there's plenty of sunlight. Luckily there's this really big surface to spread solar panels on; your balloon. Then you can electrically break down the carbon dioxide into oxygen. Or just use plants. What is it they like again? Oh, yeah, carbon dioxide...

What you don't get is much in the way of heavy elements; light organics (CHON, mostly) can be extracted from the atmosphere, but that does solve your immediate life support issues. Metals you'll need to go to the surface for, which may be a little exciting, but is perfectly doable (by machine, preferably). You're probably better off building out of organically produced carbon fibre, i.e. wood.

Venus really is one of the most hospitable planets in the solar system, after Earth. If you like planets, of course.

Found some info myself.

https://en.wikipedia.org/?title=Colonization_of_Venus

> sustaining life there will obvious continuous and hugely expensive technical input

Not if we send first our 3D printers and deep learning based robots that we are going to build soon. We just need to build a replicator and send it there to terraform for us.

Living on Venus won't save you from a future red-giant-phase Sol. Mars may not either, but it's a better bet.

Perhaps not, but it gets humans used to the idea of traveling to and living in/on/etc. worlds that aren't exactly hospitable. Additionally, the sulfuric acid clouds in Venus' atmosphere might be useful for various industrial processes.

> Great Filters

Quick link for those who haven't read Fermi paradox et al. https://en.wikipedia.org/wiki/Great_Filter

Inline summary for the lazy: If we don't see intelligent life, and the universe is as old as it is, then it must be unlikely for life to persist to a stage where we could detect it. This unlikeliness can come in two forms: either it's unlikely to ever be created (hurray, we won!) or there's some future stage that's it's unlikely to pass (uh oh us).

To elaborate on the future stage, Carl Sagan suggested that technological civilizations tend to self-destruct (e.g. perhaps nuclear war.)

You seems to think that high degrees of collective action are are a particularly good marker for judging whether human beings can accomplish space colonization. But this doesn't make sense because it's the technology and economics, not coordination, that prevents self-sustaining martian colonies. Likewise, ship technology and economic uses for overseas resources sparked European colonization, not a particularly well coordinated European monarchy.

Pardon the pun but Europe and Mars are worlds apart.

The difference between all previous human colonization and Mars is that in the past colonies were at least theoretically self sufficient. Your willingness to write off the cooperation of the rest of the human species seems shortsighted. Especially since it's the people of Earth that will be funding this lifeboat. What happens when the "Old World" find themselves embroiled in World War III thirty years into the colonization of Mars and a fungus kills all your monoculture rice? My guess is that if it comes down to winning a war or shipping 5 million tons of corn to Mars, well, you guys are going to be eating a whole lot of Soylent.

The other issue is that human colonization has always been driven by "real" pressures like limited resources, war, or economic expansion. Mars solves none of those. At best you can risk a high likelihood of dying from freezing, starving, depression, and/or cancer in order to avoid: asteroid impact, global pandemic, or killer robots. Scratch that - the killer robots will definitely find you on Mars.

> The other issue is that human colonization has always been driven by "real" pressures like limited resources, war, or economic expansion.

This is true, but only after colonization had become an economic feasibility for those who weren't enormously wealthy.

After Columbus 'discovered' the Americas, nobody in their right minds would board the next ship to the Caribbeans because it was not clear there was any reason to go. It took the funding of governments and interested frontiersmen to do the exploration, much like what we will see on any interplanetary colonization.

Only until there is enough infrastructure and a semi-self sustaining economy on Mars, will there be a low enough cost and enough interest by entrepreneurial individuals.

Yeah, folks like to compare previous terrestrial colonization with interstellar (Mars). Its fabulously incomparable. Folks in the New World could expect food plants, neighbors, congenial weather for growing, even Oxygen. All of which are largely absent on Mars.

Let's plant a colony on the peak of Mt Everest first, as a kindergarten-level test of our readiness for Mars.

You still haven't shown that there is an importance difference between the New World and Mars that justifies your focus on collectivism.

> The difference between all previous human colonization and Mars is that in the past colonies were at least theoretically self sufficient.

The colonies on mars are only useful as an insurance policy against global catastrophe when they are economically self sufficient.

> The other issue is that human colonization has always been driven by "real" pressures like limited resources, war, or economic expansion. Mars solves none of those.

Right, just like European colonization.

"colonies were at least theoretically self sufficient."

You mean like Antarctica, right?

"Especially since it's the people of Earth that will be funding this lifeboat."

Rich folks and companies, and maaaaybe governments, will be funding this--the same as all colonization efforts in the past. Consider the colonization of the Americas.

"real" pressures like limited resources, war, or economic expansion

These are still very much things to worry about on Earth. Moving to Mars doesn't solve those problems--for the Earthlings. Then again, fuck'em.

I'm not sure humanity deserves to be the species that settles the Milky Way

What does that even mean? Especially in the context of how much we've changed to get us this far and how much we would have to change to colonize a galaxy?

You might as well have looked at Homo habilis 2.8M years ago and said, "these creatures don't deserve to surf the Internet."

It's premised on the belief that humans are unworthy. It's a meaningless statement, that only reveals what opinion the person holds of humanity, while lacking any objective foundation of comparison.

It's just as likely that we are the most worthy of any species in the Milky Way or universe. Which is to say, every other intelligent life form in the galaxy is worse, or perhaps drastically worse.

In my counter opinion, I regard the human race to be truly extraordinary and good overall. I'm aware of no finer species that should settle the Milky Way instead.

I dunno. I think it's just a matter of time before the dolphins start exploring the cosmos.

Setting up a long term lunar habitat would be a very reasonable first step. Having no atmosphere means solar power is more efficient. In some spots, the soil contains water which can be split for air and fuel. Sending a few automated miners to begin producing stores and building buried habitats is something we can accomplish today, before sending anyone to live.

What I find amusing is that there are a whole ton of disaster scenarios for Earth that still leave Earth in a more hospitable condition than Mars.

> Mars is going to be his Spruce Goose

I'm a fan Elon Musk. But I think people are exaggerating that Mars mission. For me it looks like a goal for SpaceX employees. You have to somehow motivate people to work harder. Maybe I'm just a little cynical, but Elon is too smart to believe in this mission.

>Earth might get a flat tire

There is no possible "flat-tire" existential risk scenario which makes moving to Mars cheaper (man hours) than just fixing whatever happened on earth.

IMO that kills the whole thing right off the bat.

A red-giant Sol might be.

In which case no place in our Solar system is safe.

The outer planets will be safer longer. It is not known if Earth would be engulfed or not, but presumably Mars will be safer longer and might possibly survive.

https://www.youtube.com/watch?v=zc4HL_-VT2Y

We (complex life) couldn't recover from something like that. Maybe simple life could hide deep in the earth and emerge when it's safe thousands of years later.

Makes my point. After that event you now have an earth that is about as habitable as Mars is today.

That is also the absolute worst case scenario that is theoretically possible, literally a one in a billion year event. That is something we can plan for and build for now with: Anti-Asteroid technology, "Fallout" shelters/biodomes etc... Or hell, a fucking Dyson sphere (or series of them) is a million times easier/better than trying to terraform Mars.

Oh and by the way, Mars has the same risks of Asteroids as earth does so we wouldn't be out of the woods just by being on Mars.

The reality is, people like space shit and want to go to space. There is just no good reason to do it as flesh and blood humans.

Why bother with planets when we could live in space. There are lots of asteroids filled with materials floating around. If we make it economically feasible to do asteroid mining, we could expand population 1000 times. Think of what would a constellation of self-sufficient asteroid colonies and ships do for human freedom.

I agree with this. If the survival of the species is the goal we'd be far better off building a deep bunker complex on Earth than trying to get a self-sufficient colony going on Mars.

True, but it takes a lot fewer resources to thoroughly catalog and monitor all large NEOs and divert the potentially hazardous ones. Estimates I've seen put 5km impacts at an average frequency of one every 10-100 million years range, and those are survivable. Larger impacts are even less frequent, but we can still likely divert them with existing technology.

Titan in many ways is a much better candidate for colonization. It has water and an actual atmosphere.

Screw deserves or ready, you are ready to get somewhere and deserve to be there when you manage to arrive.

You may then fuck it up, and frankly it would be surprising if we didn't kill a few people trying, but that is exploration.

* Has the most habitable atmosphere of any planet save Earth

* Has billions of tons of water

* Is exposed to unconcerning amounts of radiation

* Has every economic justification for colonization

FTFY

All of those are boring technical problems, all of which can be solved with the application of money. Only physics is standing in the way.

The Earth problems, though, are a great deal more complicated. Even a sufficiently large checkbook can't solve world hunger.

Also, your whole "half the population won't admit to global warming" is some feelgood TED bullshit...I'm betting waaaay fewer than 3B (that's billion) people even remotely give a shit about the climate beyond whether or not it's going to be raining.