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Saturn's largest moon may be the only place beyond Earth where humans could live

blogs.scientificamerican.com

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Re: Saturn's largest moon may be the only place beyond Earth where humans could live

#301

Post by JdeBP »

hutzlibu wrote: post #191
bloopernova wrote: post #176

Earlier quoted context omitted.

My big idea for Venus, assuming infinite power, would be to shoot a series of big asteroids past it and use the gravity/inertia drag to make it spin faster. Then, when Venus is spinning fast enough, collide the asteroids together to give Venus a moon and tides. While all that is going on, use some sort of huge electromagnet to spin Venus' internal heavy core to provide a strong magnetic field to deflect nasty stuff f…

I assume, once you have allmost self replicating robots, who can do mining asteroids and building factories to build more of them and mine more and build more .. you would not need ten of thousands of years. Maybe even only some decades.

Just make sure that you have not invented Alastair Reynolds' "greenflies".

Re: Saturn's largest moon may be the only place beyond Earth where humans could live

#302

Post by JdeBP »

JoeAltmaier wrote: post #160
tekkk wrote: post #157

Earlier quoted context omitted.

True Venus' atmosphere is quite hostile, but from what I briefly read Venus quite probably have had a similar atmosphere with Earth (along with Mars) in the early days, before the runaway green-house effect got the best of it, so at least in theory it should be possible to transform it back. With autonomous robots perhaps it could be done in a span of million years. Maybe. A relatable analogue might be removing liqui…

I've often wondered if crashing a metropolis-sized piece of ice into Venus might help? Deflected from Saturn's rings or some such. The water vapor could cool it/reflect sunlight.

Have you considered how much kinetic energy it would have, coming all of the way down the well from Saturn?

Re: Saturn's largest moon may be the only place beyond Earth where humans could live

#303

Post by ghaff »

nitrogen wrote: post #300
ghaff wrote: post #253

Earlier quoted context omitted.

The Expanse is quite good. But the earth/Mars/Belt differences are mostly cultural at least in the TV series. The "Belters" meme in SF has been around for a long time though. See Larry Niven for example. (And I'm sure it's older than that.)

The novels portray each group has having more significant physiological differences. Naomi is supposed to be quite a bit taller than Holden, for example.

Makes sense. Easier to do in books than on the screen, especially a TV show. It's logistically just a lot easier to have everyone look like ordinary humans modulo superficial styling (and acting) differences.

Re: Saturn's largest moon may be the only place beyond Earth where humans could live

#304

Post by onlyrealcuzzo »

Ajedi32 wrote: post #291
acchow wrote: post #286

Earlier quoted context omitted.

Would living underground on Mars mitigate this?

Yes, assuming you can get to Mars fast enough to mitigate the risk during transit. The article author argues that underground living spaces are difficult to build and that Titan is therefore a better option, though personally I find that a rather unconvincing argument. Compared to the difficulty of getting to Mars, building underground habitats seems pretty straightforward in my uninformed opinion.

Haven't humans spent more than year in space? How is it not a problem from the ISS? Is that still protected by Earth's magnetic shield -- or whatever it is that protects us from Cosmic Radiation?

Re: Saturn's largest moon may be the only place beyond Earth where humans could live

#305

Post by JdeBP »

protomyth wrote: post #192
hutzlibu wrote: post #173

Earlier quoted context omitted.

Are there so many ice comets avaiable? Also, would the temperature really go down and not be negated by the kinetic impact? Apart from that, more water probably helps, if we do not need that water more urgently on mars.

Isn't the common scifi solution to drop some engineered bacteria into the atmosphere to convert the CO2 and generate a think ozone layer?

Not since sci-fi authors figured out that, given human success rates at bioengineering, the likely result is an uninhabitable planet-wide nanotech/bacterial goo that eats anyone who lands.

The ice comet solution has the added benefit of wiping out all of those pesky Martians, given the kinetic energies involved. Just ask any Pak Protector. (-:

Re: Saturn's largest moon may be the only place beyond Earth where humans could live

#306

Post by CydeWeys »

svaigsq wrote: post #273
CydeWeys wrote: post #244

Earlier quoted context omitted.

You would need a 50km long dredge. That seems completely unworkable; that's much longer than the deepest of deep mining operations we have here on Earth, and we aren't nearly as constrained on Earth as you would be on Venus. How would you even get such a thing to Venus? The only realistic way to do so would be to construct it of local materials, but now we have a chicken-and-egg problem. Plus, keep in mind that a lot…

It is probably a typo, but Mars doesn't have enough atmosphere to corrode things more than on Earth. If you need 50km long dredge, then it is a viable project in future, just like now it is with space elevator. Apparently that type of dredge will be needed to extract materials from gas planets(and 50km might not be enough), so that dredge will have to be developed anyway. The most logical solution to make habitable w…

This is very far-future stuff though. In contrast, we can colonize Mars and Titan with today's level of technology (Mars more easily more likely, because it's closer).

Re: Saturn's largest moon may be the only place beyond Earth where humans could live

#307

Post by thebiglebrewski »

TheOtherHobbes wrote: post #165
keiferski wrote: post #31

Two thoughts on this topic: 1. The film Gattaca (1997), in addition to being an excellent, inspiring film all around, centers on an aspiring astronaut's upcoming trip to Titan. Highly recommended. - https://www.youtube.com/watch?v=lZa83dTf4JA 2. The colonization of Venus is also a fascinating idea that isn't talked about much in comparison to the Moon or Mars. Essentially, the surface is too hot for colonization, but…

Unless you're planning to build a literal castle in the sky out of convenient gasses, this is completely unworkable. Even at that altitude the cloud layer is still very turbulent and very toxic, and no structure will be absolutely gas-tight. And if the temperature is 75 °C outside, it's going to take insane amounts of energy to keep the inside of your hab cool - especially if it's made of metal and not rock. (A thin…

"Come TheOtherHobbes, you belong here with us, among the clouds..."

- Lando Venrissian

Re: Saturn's largest moon may be the only place beyond Earth where humans could live

#308

Post by xref »

onlyrealcuzzo wrote: post #304
Ajedi32 wrote: post #291

Earlier quoted context omitted.

Yes, assuming you can get to Mars fast enough to mitigate the risk during transit. The article author argues that underground living spaces are difficult to build and that Titan is therefore a better option, though personally I find that a rather unconvincing argument. Compared to the difficulty of getting to Mars, building underground habitats seems pretty straightforward in my uninformed opinion.

Haven't humans spent more than year in space? How is it not a problem from the ISS? Is that still protected by Earth's magnetic shield -- or whatever it is that protects us from Cosmic Radiation?

Astronauts are still within the Van Allen belts so largely protected unless a solar flare deforms the field enough to weaken their protection.

https://en.m.wikipedia.org/wiki/Van_Allen_radiation_belt

Re: Saturn's largest moon may be the only place beyond Earth where humans could live

#309

Post by CydeWeys »

Someone wrote: post #267
CydeWeys wrote: post #241

Earlier quoted context omitted.

Mars has a lot more benefit here, in that it has a normal-length day. Much better to reliably have sunlight for roughly half of every day than to rely on a few polar areas that are in sunlight most of the time. The equator of the Moon is more suitable for other reasons, so what are you going to do, put the solar panels at the poles and run long power lines down to the equatorial regions where the power is used? Nah.…

On the minus side, Mars gets less than half the amount of sunlight per square meter.

That's true, but I think the fact that you get light reliably every day is still a big point in its favor. It's probably a lot less mass total to send up twice the solar panels and 18 hours' worth of batteries vs half the solar panels but 16 days' worth of batteries. Solar panels are pretty light; batteries are not.

Re: Saturn's largest moon may be the only place beyond Earth where humans could live

#310

Post by ggffryuuj »

palisade wrote: post #296
beefman wrote: post #201

The dangers of radiation on Mars are greatly exaggerated. The dangers of low gravity on Titan and elsewhere are greatly understated, as is the immense distance between Mars and Titan. A floating habitat on Venus is harder and less attractive in every way than a rotating space station, which is clearly our next milestone in space. In terms of planets though, there's a reason Mars gets the most attention: it's obviousl…

A floating habitat on Venus is actually more attractive. Venus (upper atmosphere): -human livable temperatures with modest temperature control -Earth-like pressure (Himalayans) leads to slow leaks that can be patched, and pressure can be increased inside to stop the leaks inward -protected by thick atmosphere from radiation, meteors, asteroids -strong magnetic field against radiation -atmosphere still thin enough for…

Literally everything you said is wrong except projectiles and space stations. Magnetic fields are easy to make. Wind storms and unbreathable air and radiation and projectiles don’t matter if you’re underground. The idea that a floating city is better than a city cemented in soil is laughable. Good luck maintaining that Teflon coating on literally every exterior surface.
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