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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

#251

Post by Ajedi32 »

Everyone in the comments here debating the merits of Mars vs the Moon vs Titan seems to have missed the whole point of this article. The author is arguing that anywhere other than Titan is infeasible due to recent research suggesting that Galactic Cosmic Rays cause significant brain damage (not just increased risk of cancer). In fact, the article argues that the danger is so severe that even getting to Titan quickly enough to mitigate the risk of brain damage during the trip will be a major challenge.

If true, this complicates things significantly. Does anyone know if the dangers of Galactic Cosmic Rays are really as significant as the author is claiming? The author references the 2016 paper "Cosmic radiation exposure and persistent cognitive dysfunction"[1] which was a study conducted on mice. Has there been any further research into the possible effects of cosmic radiation exposure on humans?

[1]: https://www.nature.com/articles/srep34774

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

#252

Post by kjs3 »

btkramer9 wrote: post #222
kjs3 wrote: post #215

Earlier quoted context omitted.

Unless you think that the Moon is the obvious next milestone in space.

The only thing going for the moon is its proximity to Earth. Mars has more than double the gravity of the moon, an atmosphere, nearly earth-like day night cycle and satellites have a much easier time orbiting mars

The only thing going for the moon is its proximity to Earth.

Oh...that's all. So let's ignore for just a second the logistical advantages of figuring out how to actually mount a manned mission to build something non-trivial on another body when you're 3 days away, not 6 months away. Pretend that isn't important.

The moon has water, raw materials, enough gravity things don't just float away, abundant solar and we've already figured out how to get people there and back. We already have an MVP to build on.

On the other hand, a manned Mars mission is still an un-funded wank-fantasy with a disturbingly high failure rate for the unmanned attempts.

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

#253

Post by ghaff »

wmeredith wrote: post #242
rootbear wrote: post #230

Earlier quoted context omitted.

I, too, have concerns about how well humans will thrive in low gravity (the moon, Mars, etc). Over time, we could evolve a branch of humanity, "Homo ares", for Mars, but it won't be easy. Venus is just a tragic waste of a planet. So close to Earth in size, so wrong in every other way.

> Over time, we could evolve a branch of humanity, "Homo ares" These were called Belters (as in asteroid belt) in the excellent book series The Expanse, which is also an excellent sci-fi show available on Amazon.

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.)

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

#254

Post by lokedhs »

rbanffy wrote: post #162
entropicdrifter wrote: post #152

Earlier quoted context omitted.

The thing is, if we were to develop the tech needed to cool Venus, it would be orders of magnitude cheaper to just use it here on earth to offset CO2/CO emissions and reverse the greenhouse effect.

That does nothing in terms of increasing Earth's surface area. Either we cap the population or we expand to other habitats.

There are vast expanses of desert in Sahara that no one lives in. That land is much easier to settle than another planet, yet we don't do that.

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

#255

Post by btkramer9 »

jbattle wrote: post #250
btkramer9 wrote: post #233

Earlier quoted context omitted.

I'm not so sure about that. It takes more delta-v to get to the moon than mars and both are still too far for immediate response to emergencies. Sure the moon has the advantage of emergency assistance of a few days (?) but I don't think that's more valuable than all of Mars's pros

> It takes more delta-v to get to the moon than mars Is that true? I can't see how that'd be true, unless maybe you are considering aerobraking to enter mars orbit and parachutes for landing on the surface (?)

yes with aerobreaking but I still believe that includes a propulsive landing after. The moon has no atmosphere so it has to be propulsive landing 100%

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

#256

Post by bobloblaw45 »

rootbear wrote: post #230
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…

I, too, have concerns about how well humans will thrive in low gravity (the moon, Mars, etc). Over time, we could evolve a branch of humanity, "Homo ares", for Mars, but it won't be easy. Venus is just a tragic waste of a planet. So close to Earth in size, so wrong in every other way.

Moon humans would be so weak I bet it would be easy to beat them up and steal all their moon cheese.

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

#257

Post by svaigsq »

rootbear wrote: post #230
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…

I, too, have concerns about how well humans will thrive in low gravity (the moon, Mars, etc). Over time, we could evolve a branch of humanity, "Homo ares", for Mars, but it won't be easy. Venus is just a tragic waste of a planet. So close to Earth in size, so wrong in every other way.

Venus has 80% of Earth mass. Mars has 10% of Earth Mass. The simple math suggests, that these planets are destined to be combined in some distant future, but not by current civilization, so there is no real reasons to be concerned about anything at all.

Any of those projects of colonization in space is even greater waste of resources, compared to colonies in northern Canada, Antarctica, artificial islands or underwater cities.

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

#258

Post by btkramer9 »

kjs3 wrote: post #252
btkramer9 wrote: post #222

Earlier quoted context omitted.

The only thing going for the moon is its proximity to Earth. Mars has more than double the gravity of the moon, an atmosphere, nearly earth-like day night cycle and satellites have a much easier time orbiting mars

The only thing going for the moon is its proximity to Earth. Oh...that's all . So let's ignore for just a second the logistical advantages of figuring out how to actually mount a manned mission to build something non-trivial on another body when you're 3 days away, not 6 months away. Pretend that isn't important. The moon has water, raw materials, enough gravity things don't just float away, abundant solar and we've…

I've mostly addressed this in the siblings comments. Mars has all the same resources and more. The way humans went from the moon's orbit to surface is so far off from how it would be done today I would hardly call it and MVP. Both are too far for any meaningful emergency response. I believe the ongoing work with starship debunks your claim of an "un-funded wank-fantasy". The moon also has a disturbingly high failure rate for the unmanned attempts.

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

#259

Post by dumbfoundded »

Ajedi32 wrote: post #251

Everyone in the comments here debating the merits of Mars vs the Moon vs Titan seems to have missed the whole point of this article. The author is arguing that anywhere other than Titan is infeasible due to recent research suggesting that Galactic Cosmic Rays cause significant brain damage (not just increased risk of cancer). In fact, the article argues that the danger is so severe that even getting to Titan quickly…

There's danger everywhere outside of Earth. All of the problems seem fixable except for gravity. We don't know if humans can even be born and raised in low gravity environments.

Venus would seem to be the right choice for a long time scale. Maybe we could use the practice too at learning how to reverse a runaway greenhouse effect.

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

#260

Post by logfromblammo »

wmeredith wrote: post #242
rootbear wrote: post #230

Earlier quoted context omitted.

I, too, have concerns about how well humans will thrive in low gravity (the moon, Mars, etc). Over time, we could evolve a branch of humanity, "Homo ares", for Mars, but it won't be easy. Venus is just a tragic waste of a planet. So close to Earth in size, so wrong in every other way.

> Over time, we could evolve a branch of humanity, "Homo ares" These were called Belters (as in asteroid belt) in the excellent book series The Expanse, which is also an excellent sci-fi show available on Amazon.

Or evolve a branch of humanity that uses non-biological, radiation-hardened, easily-maintained, low-mass machines, instead of meat that doesn't grow correctly in low acceleration, uses chemical energy storage with no power generation capacity, and which gets scrambled without megagrams of shielding.

That is, develop general AI with a sense of responsibility and filial duty to its parent species, and which won't turn us all into paper clips.

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