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Let's Colonize Titan

blogs.scientificamerican.com

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Re: Let's Colonize Titan

#381

Post by diziet »

wallace_f wrote: post #378
s_q_b wrote: post #337

Earlier quoted context omitted.

Dense atmospheres also make it much easier to enter, descend, and land (EDL), since they can be used for drag parachutes and atmospheric braking. The atmosphere on Mars by comparison is awful for landing spacecraft. It has just enough density to jumble the craft's trajectory, so vacuum-based EDL techniques similar to the moon landing are impossible, but it's too thin for atmospheric EDL systems similar to those used…

I wonder if it would also make it easier to exit--having dense atmosphere and low gravity. It might be possible to easily fly a rocket on the underbelly of a low-powered aircraft and launch it from the upper atmosphere.

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 velocity harder, as you need to actually do it 'high up' where the atmosphere is not as dense, say from something similar to Low-Earth Orbit.

Re: Let's Colonize Titan

#382

Post by wallace_f »

dsjoerg wrote: post #201
banach wrote: 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…

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 - Economists and doctors work together to develop an affordable nutritional product to combat malnutrition. Academic research is invested in the endeavour. Company comes along and patents the product to seek profit at the cost of humans suffering malnutrition b) All people will always grab whatever self-interest is available to them despite harm to their group, unless social structures are in place to align their incentives with those of the group. c) Most people inherently are motivated to work together due to social nature of our species, only a minority wishes to be truly self-interested despite the welfare of their group.

Re: Let's Colonize Titan

#383

Post by wallace_f »

blueprint wrote: post #189
banach wrote: 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…

> 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). What a horrible lie to spread. What you said is hardly the case at all. Scientists have known for many decades that Earth is already beyond its carrying capacity. Multiply tha…

> Scientists have known for many decades that Earth is already beyond its carrying capacity.

People were saying this before the Enlightenment. There is no evidence that this is true.

Our population is probably not sustainable with the way that we currently treat the environment, but that doesn't mean we can't evolve our sophistication. This has been the same forever.

Alternatively, a population on earth of 50 people is arguably not sustainable if they spend their efforts trying to kill each other with the world's stockpile of nuclear weapons.

There's no such thing as an inherent carrying capacity of people irrespective of technology or total biomass.

Re: Let's Colonize Titan

#384

Post by JoeAltmaier »

s_q_b wrote: post #334
JoeAltmaier wrote: post #321

Earlier quoted context omitted.

And would it really be ok to walk around in methane in just a coat? Wouldn't your skin react?

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?

Re: Let's Colonize Titan

#385

Post by wallace_f »

diziet wrote: post #381
wallace_f wrote: post #378

Earlier quoted context omitted.

I wonder if it would also make it easier to exit--having dense atmosphere and low gravity. It might be possible to easily fly a rocket on the underbelly of a low-powered aircraft and launch it from the upper atmosphere.

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 will rephrase it:

On earth piggy-backing or ballooning a rocket to the upper atmosphere is not usually practical due to the ability to produce lift in the atmosphere relative to the size and weight of the rocket.

However, on Titan with a thick atmosphere, imagine flying one to the upper atmosphere which would take relatively little energy in a thick atmosphere with low gravity, thereby escaping much of the problem of atmospheric drag and using it to your benefit instead.

That's just the thought process, of course I don't of anyone that has done the math on the most efficient way to launch from Titan, yet.

Re: Let's Colonize Titan

#386

Post by jonshariat »

stcredzero wrote: post #310

Although the atmosphere lacks oxygen, water ice just below the surface could be used to provide oxygen for breathing and to combust hydrocarbons as fuel. Red flag! It's a nonstarter to extract oxygen from water, use it to burn a hydrocarbon, then try to come out with more useful energy than you started with. This might have some use as an energy storage scheme, as storing hydrocarbons can be cheaper and more energy d…

Also I always wonder why these articles gloss over the health issues related to low gravity. Thats not something we've figured out either. Astronauts lose a lot of bone density in space.

Re: Let's Colonize Titan

#387

Post by [deleted] »

internaut wrote: post #103
cstross wrote: post #74

Earlier quoted context omitted.

a magic box which would reliably and cheaply convert black/gray water to high quality drinking water and turn poop and organics into energy bricks to eliminate sewage plants and septic tanks seems like a technology we should have invented a long time ago. We have invented such a "magic box" -- but it's large-scale: that's what municipal sewage farms mostly do (modulo the final step of turning poop into energy bricks:…

I still want my magic box. Here is why: - Get rid of water and sewer pipes. That would be huge. Together with passive house technology each and every house in a city, town or countryside would be 'off grid'. That kind of independence would make our infrastructure much less fragile. Building downwards (a recent topic) will be easier. - Our magic box is an isolation point for dangerous and toxic substances. That will p…

[deleted]

Re: Let's Colonize Titan

#388

Post by Bluestrike2 »

kilpela wrote: post #351
acchow wrote: post #190

Earlier quoted context omitted.

I think we should colonize other planets because we can. Not as a solution to any problem. I will defer to The West Wing to explain: https://www.youtube.com/watch?v=9yUHnERJ0zs

What you are describing is inverse vandalism. If we ignore the problems of here and now, the realization of a future where we colonize the stars may never occur. Obligatory quote: Yeah, yeah, but your scientists were so preoccupied with whether or not they could that they didn't stop to think if they should. - Dr. Ian Malcolm. Our focus should not be on whether we can do something. We should carefully consider why we…

As odd as it may seem, the human race is fully capable of accomplishing both space-expansion efforts and cleaning things up here on Earth. More than that, space opens the door to a wealth of possibilities for ameliorating or even solving many of the major problems we face today. That includes environmental efforts and energy production.

Even if we were to pursue a massive space race, it'd only consume a relatively small fraction of humanity's industrial capability and resources as they exist today. In the context of a long-term terraforming effort, after a significant space-borne industry has been created, these sorts of binary comparisons become all the more laughable.

Re: Let's Colonize Titan

#389

Post by iainmerrick »

babyrainbow wrote: post #364
etangent wrote: post #243

Earlier quoted context omitted.

> Make eco damaging behaviours "uncool" As 2016 had shown, we're well past the point where it was possible for a centralized (or even moderately stratified) entity to declare certain behaviors "uncool". Changing human culture without changing human nature introduces huge arbitrage opportunities for malicious actors and demagogues and increases overall existential risk.

>s 2016 had shown, we're well past the point where it was possible for a centralized (or even moderately stratified) entity to declare certain behaviors "uncool". Which event has shown? > Changing human culture without changing human nature introduces huge arbitrage opportunitie... What has "culture" to do with this? Behaviour is not the same as culture. Some one might have a habit of throwing garbage on the roads/pu…

>s 2016 had shown, we're well past the point where it was possible for a centralized (or even moderately stratified) entity to declare certain behaviors "uncool".

Which event has shown?

I imagine they're talking about the recent US election, for one. For pretty much the whole campaign, including primaries, everyone pointed out all the ways in which Trump was a terrible, completely unsuitable candidate, and he won anyway.

Re: Let's Colonize Titan

#390

Post by ChuckMcM »

foobarian wrote: post #374
ChuckMcM wrote: post #356

Earlier quoted context omitted.

I don't disagree with your red flag, I do however note that there are other ways of getting electricity out of hydrocarbons without cracking water. Specifically a the use of fuel cells. If you feed methane to a Bloom Energy fuel cell after initially filling it with some liquid water, it will generate 250kW of power as long as you feed in methane.

But... where does it get the oxygen?

From the water using steam reforming as I understand it, which is recovered 100% when the cell is generating power. The only consumable ends up being the methane.
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