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Let's Colonize Titan

blogs.scientificamerican.com

441–450 of 508 posts

Re: Let's Colonize Titan

#441
post #334

Earlier quoted context omitted.

The temperature is so cold that it would freeze your body if you were exposed, so you would still need an airtight seal. But the atmospheric pressure is high enough that you wouldn't need a bulky vacuum-proof pressurized spacesuit.

I'm thinking if the surface temperature were hundreds of degrees below, and the air were thick enough for conduction, that the suit would have to be a vacuum-insulation type of thing anyway?

No. Ambient-pressure-airtight is much easier than vacuum-airtight.

A drysuit for scuba diving is ambient-pressure airtight, basically just a neoprene coverall with sealed seams. It's easy to move around in.

But take away the external pressure, and you're in the middle of a 15 psi balloon,w which wants to be a sphere, not human-shaped. It becomes difficult to bend your limbs and fingers. Rotating a shoulder, neck, or wrist causes the suit to twist in like a party balloon. Anywhere the cross-section is not circular, it wants to be more circular.

You either need a hard shell suit, a tolerance for this difficulty, or a lot of engineering.

Re: Let's Colonize Titan

#442

Earlier quoted context omitted.

Even if everybody eats twice as many animals as they do now and moves further away from their workplaces, Earth will remain a more livable place than Titan. Maybe that isn't true if we kick off a nuclear war, but it probably still is. Global warming? Titan's atmosphere is literally not breathable, and the outside temperature is colder than any place on Earth. Food scarcity? Nothing grows on Titan. If you're growing i…

You are only focusing on the drawbacks of titan, and not on its significant benefits. Titan has practically limitless amounts of fuel in the form of oceans of flowing hydrocarbons. Titan should be though of as a resource, not necessarily as a sprawling multi-billion person supporting planet.

Hydrocarbons are useless without an oxydant.

Re: Let's Colonize Titan

#443

Earlier quoted context omitted.

All it takes is one large-ish asteroid to wipe out everything except maybe a few lucky smaller organisms/viruses that get ejected into the open space. AFAIK, a 300-mile diameter asteroid would sterilize the planet. That's why we should become multiplanetary species sooner, rather than later.

But what is the probabilistic timeline on a large asteroid hitting us vs. rendering the planet uninhabitable by our own devices? We aren't currently looking like a great bet to last thousands of years longer, forget the million-year intervals on which large asteroids are a serious threat.

The planet is not even close to uninhabitable. Humans are resilient, and can solve problems when they become real.

Take the global warming. We actually know how to solve it - we just don't, because it's not a real problem yet (not on a large scale at least), and it costs money to solve. We can put mirrors in space or on the surface of the planet to cool it. Yes, it's expensive, but it's doable.

Pretty much no scenario makes ALL of our planet uninhabitable to humans. Except a big f*ng asteroid.

Re: Let's Colonize Titan

#444
post #106

I think that, before colonizing other planets, we should start by realizing that Earth can easily sustain human kind for the foreseeable future, given some pretty modest tweaks to our way of life (compared to "going multi-planetary" that is). If we start valuing quality over novelty, stop eating animal-based foods and re-organize to live closer to where we work, we can stop the consumption and that is taxing our ecos…

Do you seriously think that any of the following global political challenges: - convince everyone on Earth to implement changes that are bad for them, like not eating animal-based foods, with only the promise of "maybe in 200 years your descendants, should your line not be extinct by then, will benefit" as compensation - reorganise every single human settlement and/or social structure on Earth to put people closer to…

Well ok, let's just pretend everything's fine and carry on exactly as we are.

Re: Let's Colonize Titan

#445
post #375
post #219

Earlier quoted context omitted.

> regular and predictable commutes are best done with public transit. In places where public transit has dense enough coverage to make commute times reasonable, yes. But that's not most places where Americans are commuting.

He's not saying the public transit solutions are implemented yet. For that to happen, people would need to re-allocate their funds from buying expensive private cars to a new public transit system.

That's only half the problem; you also need to reallocate housing from the diffuse suburban homes suitable for car-life to the concentrated cores of housing around the local stops in your mass transit system.

Which is not to say it shouldn't be done, but bootstrapping a mass transit system is a long, slow process that involves throwing away a lot more than our existing cars & highways.

Re: Let's Colonize Titan

#446

Earlier quoted context omitted.

Colonizing other planets is _way_ easier than doing any of the things you listed. The hardest thing is getting people to cooperate, especially against their individual self interest, as they themselves see it. Colonizing other planets requires getting a much smaller group of people to cooperate, and it will be in their individual self interest to do so.

> especially against their individual self interest, as they themselves see it. I'm curious how other people view this, which one of the following most accurately depicts reality: a) There will always be opportunists who take advantage of self-interested opportunities despite there being a larger group whom will not be willing to grab these opportunities for conceivably moral/ethical reasons a.Example) Plumpy'Nut - E…

Any answer to this would be a vector.

Also, people are more prone to be selfish in some environments than in others. One relevant example is that people that were taken advantage of are more prone to it than people that weren't.

And you'll have to add policing efficiency to the equation. We are pretty great in forcing people to cooperate.

Re: Let's Colonize Titan

#447
post #420

Earlier quoted context omitted.

>If we re-distribute our wealth, population growth will subside. I don't see how redistributing wealth will reduce population growth. Natural selection ensures the population will grow and wealth redistribution will ensure it doesn't grow at a rate that's proportional to the growth in resource production. Moreover, I don't see how you can get 300 million people in the US, let alone 7 billion people on Earth, to all a…

>I don't see how redistributing wealth will reduce population growth. Developed countries have lower population growth due to better access to sex education, contraceptives and healthcare. If "redistributing" wealth gives big chunk of Earth population access to those three one can expect to have reduced population growth. This is backed by studies that just giving women access to education reduces fertility as well a…

>Developed countries have lower population growth due to better access to sex education, contraceptives and healthcare.

High income that mostly constitutes personal earnings is different than high income that mostly constitutes guaranteed government transfers. The personal responsibility required to maintain the former creates an incentive to avoid having children one is not financially capable of support. The lack of any such requirement in the latter creates the opposite incentives.

Moreover, the correlation between high resource availability and low population growth is a historical anomaly. For most of history the opposite has been the case. There is no guarantee there won't be a return to the historical norm. Natural selection will favor the growth of population groups that respond to high resource availability with larger families, so this is what we logically expect to predominate.

Finally, you never answered how you would get 300 million people in the US, let alone 7 billion people worldwide, to agree to redistribute their personal assets.

Re: Let's Colonize Titan

#448
post #106

I think that, before colonizing other planets, we should start by realizing that Earth can easily sustain human kind for the foreseeable future, given some pretty modest tweaks to our way of life (compared to "going multi-planetary" that is). If we start valuing quality over novelty, stop eating animal-based foods and re-organize to live closer to where we work, we can stop the consumption and that is taxing our ecos…

Apart from sudden extinction events like a Giant Meteor™ hitting earth - isn't earth still going to be vastly more friendly than an outer solar system body, even if we ruin it?

I mean after a new ice age, a complete runaway greenhouse process, an episode waterworld, a complete thermonuclear mayhem, etc. etc. the ruined earth will still be easier to "re-colonize" than Titan or Mars.

If we need space suits to go outside on Earth because its +100 or -100 degrees C or there is radiation everywhere etc - we are still likely to have an environment that is friendlier than Mars/Titan. It's like he says in the article - if we are going to live in caves we might as well do it on Earth. Now - if we worry about our survival as a species then colonizing makes perfect sense. If we worry about destroying the planet, then I don't get it. We can't possibly destroy Earth to a point where it is less hospitable than Titan?

Re: Let's Colonize Titan

#449
post #381

Earlier quoted context omitted.

Leaving the gravity well of a planet depends on delta-v needed to leave that gravity well, not just on getting high enough in the atmosphere. We can easily send balloons to 'space' on earth, but they don't have the speed to achieve escape velocity. Delta-v for Titan is around 2.6km/s (compared to 11.2 on Earth, and 5.0 on Mars). Atmosphere (especially a dense one that causes drag and heating) makes achieving escape v…

>Leaving the gravity well of a planet depends on delta-v needed to leave that gravity well, not just on getting high enough in the atmosphere. I'm well aware of that, I think you didn't see what I was trying to say. > as you need to actually do it 'high up' where the atmosphere is not as dense, say from something similar to Low-Earth Orbit. That was actually the thought process behind it, not the problem with it. I w…

That's an interesting thought, but I doubt it works. Density should go roughly like

    exp(-gravity * height)
Lesser gravity implies slower decrease of density with height. "Titan's lower gravity means that its atmosphere is far more extended than Earth's; even at a distance of 975 km, the Cassini spacecraft had to make adjustments to maintain a stable orbit against atmospheric drag." https://en.wikipedia.org/wiki/Atmosphere_of_Titan

Re: Let's Colonize Titan

#450
post #342

Earlier quoted context omitted.

My commute is 12-15 minutes by car and 55 minutes to an hour and a half by bus (assuming the buses were actually on time, which is unrealistic here). Plus either time to make and pack a lunch, or the time to walk to a fast food restaurant near work for lunch. Plus a similar commute time back. It's somewhat faster (but more dangerous) to ride a bicycle. If my goal is a fast, safe commute, I don't have a realistic opti…

Get a moped. Safer than your pushie if your lacking the infrastructure, the only reason riding a bike is so dangerous anyway is the amount of cars on the road. Notice that basically all the cars on the road have 1 person and 4 empty seats every morning? You're burning all the fuel to basically move an empty car around, a 50cc moped is burning 36 times less fuel per power stroke than my corolla (ignoring combustion ef…

I have a Kawasaki KLR 650 and a Toyota Prius. My Toyota uses less fuel than my motorcycle. A lot more energy went into making the Toyota, so maybe over the lifetime of the vehicles the motorcycle is still better. On the other hand, I can carry four people in the Toyota along with quite a bit of cargo in the trunk and the fuel consumption doesn't change all that much.
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