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There’s no planet B

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Re: There’s no planet B

#111

Post by PaulHoule »

Not like we can count on it, but most of the living space in the universe is not on the surface of planets but rather could be built out of carbon and water rich asteroids (though it is Nitrogen that looks like the hardest thing to get right now)

https://arxiv.org/abs/2011.07487

is a plan to build a structure that could support a population larger than the Earth. (I'd read that paper not just as boosterism or science fiction but also as a criticism of other space colonization schemes whose problems it addresses.)

That kind of colony would be a solar economy but with deuterium-deuterium fusion you could support a similar lifestyle in the outer solar system or interstellar space. Hopping from comet to comet with a comfortable lifestyle, travelers could make it from star to star in 10,000 years ago but they might be completely uninterested in comparatively dry inner solar system bodies like the Earth and Mars when you could cut up a planet like Pluto to create much more living space.

Mars is a small planet compared to the Earth. If you actually want to widen mankind's prospects, look to the asteroid belt, where it takes just 10⁷ kg of material per person to build a habitat as opposed to the 10ⁱ⁶ kg of planet needed to support you.

So I think asteroids are a more interesting target than Mars, probably not that much harder but a much larger reward. Mars is a smaller planet than the Earth and would have a hard time outgrowing us, but Ceres really could be a path to the stars.

Re: There’s no planet B

#112

Post by chriswarbo »

jbu wrote: post #4
chriswarbo wrote: post #2

> This futuristic dream-like scenario is being sold to us as a real scientific possibility, with billionaires planning to move humanity to Mars in the near future. As far as I'm aware, no billionaire has ever said anything about "moving humanity" to Mars or anywhere else; except to dismiss such claims as nonsense. Nobody is "planning" such a thing; let alone for "the near future". Musk wants there to be a colony on M…

True. But whenever I discuss the climate crisis/future with non-billionaires (i.e. most people I know) there's a significant population of 'don't worry we'll move to mars if it gets too bad'. I mean, have you been on HN for long?

Refuting those claims doesn't require misattributing them.

Re: There’s no planet B

#113

Post by alienalp »

roryisok wrote: post #87
alienalp wrote: post #78

Earlier quoted context omitted.

In reality this is just a fantasy. It is not possible for a healthy human to really care about survival of human race in case of something catastrophic happening and wiping out humanity.

Why? Healthy people care about having descendants they'll never meet.

Survival of human race is very different then caring about descendants. Yet as you are live witnessing right now some people barely care about that and most people do not even think about it. If earth to be wiped out by a meteor and there was a ship with limited space to colonize another planet people would fight for that space even if it would mean decreasing success chance of mission.

Re: There’s no planet B

#114

Post by Maursault »

chitowneats wrote: post #110
Maursault wrote: post #108

Earlier quoted context omitted.

140M people are born every year, but only 60M people die every year. We'll need to do something if the birth rate keeps increasing or even stays steady, or even slows down, but the death rate stops.

"if the birth rate keeps increasing" is another of your assumptions that most demographers find unrealistic. Rising incomes have solved this problem (perhaps too well) in every single advanced economy on Earth. Is your assumption that certain developing societies aren't capable of this? Or won't do this? If that's the case, why? Why are we extrapolating current birth rates in places like West Africa 100 years into th…

> Rising incomes have solved this problem (perhaps too well) in every single advanced economy on Earth.

This is an unrealistic fantasy. 90% of all the available wealth is held by the top 1%. Cost of living increases have never matched inflation. The most advanced society Earth has ever seen is sliding slowly backwards. Few are getting richer, nearly everyone is getting poorer. Your solution is elusive.

> Is your assumption that certain developing societies aren't capable of this? Or won't do this? If that's the case, why?

What are you talking about? Look around. I don't see this utopia of yours anywhere now or before, so why do you expect it will just materialize in the future?

Re: There’s no planet B

#116

Post by chriswarbo »

paulryanrogers wrote: post #61
Majestic121 wrote: post #34

Earlier quoted context omitted.

> It's that some people will go to Mars and the rest of us can die out here. If the alternative is that no-one goes to Mars and everybody dies, I'm OK with only some people going there. There are a lot of possible catastrophes that can wipe us out from Earth, and not all of them are preventable or due to mankind. Starting to move towards a direction were we at least have a temporary alternative, even if the alternati…

There is a risk that seriously entertaining or promoting a plan B undermines efforts to execute plan A, sustainable lifestyles on Earth. Both are hard, yet quick and high visibility wins may be easier with Mars. "Look humans set foot on it!" (After X failed attempts and even the arrivals died soon after.) "Mars now has a habitat module!" (Vulnerable to radiation and completely dependent on shipments from Earth.)

That argument makes sense for e.g. carbon capture schemes, or geoengineering: they seem like easy fixes, compared to the necessary sustainability improvements we actually need to make.

"Move to Mars" sounds the opposite of easy.

Re: There’s no planet B

#117

Post by lapcat »

fleventynine wrote: post #109
lapcat wrote: post #102

Earlier quoted context omitted.

> I'm skeptical of any such top-down hierarchy surviving for generations Have you seen [gestures broadly] the world? People are people regardless of where you put them. There's no reason to believe that Mars will magically become a political paradise, simply because it's a long distance away from here. > Mars has the significant advantage of having a much shallower gravity well. But vastly fewer people, vastly smalle…

> There's no reason to believe that Mars will magically become a political paradise, simply because it's a long distance away from here. Obviously it won't be a paradise. But the natural environment will select for hard-working individuals with grit, determination, and community spirit.

> the natural environment will select for

What do you mean by this?

Natural selection AKA "survival of the fittest" only works over the course of thousands or millions of years. Otherwise, Mars would be pretty much stuck with whatever people it (hypothetically) had. Especially if you're talking about a colony that decides to make itself independent of Earth.

On Earth, we can be selective of who we would (hypothetically) send to Mars. But wouldn't we select loyalists to ourselves? Unless... we make Mars a penal colony. ;-)

Also, "community spirit" can mean obedience to the strict existing hierarchy, for the preservation of the community.

Re: There’s no planet B

#118

Post by chitowneats »

Maursault wrote: post #114
chitowneats wrote: post #110

Earlier quoted context omitted.

"if the birth rate keeps increasing" is another of your assumptions that most demographers find unrealistic. Rising incomes have solved this problem (perhaps too well) in every single advanced economy on Earth. Is your assumption that certain developing societies aren't capable of this? Or won't do this? If that's the case, why? Why are we extrapolating current birth rates in places like West Africa 100 years into th…

> Rising incomes have solved this problem (perhaps too well) in every single advanced economy on Earth. This is an unrealistic fantasy. 90% of all the available wealth is held by the top 1%. Cost of living increases have never matched inflation. The most advanced society Earth has ever seen is sliding slowly backwards. Few are getting richer, nearly everyone is getting poorer. Your solution is elusive. > Is your assu…

[flagged]

Re: There’s no planet B

#119

Post by 1970-01-01 »

Let's assume we're not going anywhere because it's extremely hard. Now let's also assume the last century includes all of the methods to engineer energy mankind will ever create. See! There's no planet B! Colonization is impossible!

Re: There’s no planet B

#120

Post by paulryanrogers »

ben_w wrote: post #101
paulryanrogers wrote: post #85

Earlier quoted context omitted.

Gravity primarily and the lack of carbon on the surface. Also the lack of a magnetic field to maintain atmosphere and shield from radiation.

Gravity can be solved the same way as on a space station (spinning), you just don't put the floors at the same angle because you're adding the constant vector from the mass to the frame of reference vector from being in a centrifuge. Artificial magnetic fields are easy. Sometimes we do them when we don't want them. Carbon is 1/3rd of the atmosphere (such as it is) by mass. Conveniently in solid form near the poles du…

Spinning enough to produce usable gravity is non-trivial and building something like that in space requires overcoming Earth's own gravity well.
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