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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

#261

Post by JdeBP »

keiferski wrote: post #28
pyrale wrote: post #21

Earlier quoted context omitted.

Mainly because right now, any significant endeavour is tied to using massive amounts of fossil fuel. As long as it will be the case, we won't be able to start new, large scale projects without jeopardizing our ability to live on earth.

> Mainly because right now, any significant endeavour is tied to using massive amounts of fossil fuel. But does that actually matter in space? I am asking out of genuine curiosity here: does using fossil fuels in space have any real downside? There is no atmosphere, ergo no greenhouse effect. The vastness of space would seem to swallow up any sort of pollution.

Stuff that you throw away in space does not go away. It tends to go into orbit, an orbit that either intersects yours later on or intersects someone else's. It may even go into orbit around you, depending from circumstances.

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

#262

Post by protomyth »

hutzlibu wrote: post #220
protomyth wrote: post #202

Earlier quoted context omitted.

Why yes, let's test out something that can kill billions on Earth before trying it on an uninhabited area.

I think he meant, before we try to mess with a planet far away, we have a CO2 problem here on earth already urging to be solved in general. Not necessarily, to experiment wildly in the process here on earth.

I would bet the solution for Earth is going to be wildly different than one used on Venus. Earth will require carbon removal that can safety be used with people present. The Venus solutions all sound very, very unfriendly to be present for.

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

#263

Post by svaigsq »

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

If Mars has atmosphere, then Moon has equally useless atmosphere, too. Despite differences in day length, Moon can gather more solar power, than Mars and energy is everything. Besides, those sattellites are gonna crash.

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

#264

Post by btkramer9 »

svaigsq wrote: post #257
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.

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 underwat…

I think you underestimate how radically different a world we'd live in if we had and inter solar system logistics network between colonies, earth and asteroids. It would be like another industrial revolution with untold and unimaginable changes. Likely with artificial islands, underwater cities, climate change reversal existing as mere side effects.

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

#265

Post by throwaway894345 »

protomyth wrote: post #262
hutzlibu wrote: post #220

Earlier quoted context omitted.

I think he meant, before we try to mess with a planet far away, we have a CO2 problem here on earth already urging to be solved in general. Not necessarily, to experiment wildly in the process here on earth.

I would bet the solution for Earth is going to be wildly different than one used on Venus. Earth will require carbon removal that can safety be used with people present. The Venus solutions all sound very, very unfriendly to be present for.

It was a joke, relax.

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

#266

Post by _sbrk »

Symmetry wrote: post #81

I'd tend to Jupiter's outer big moon, Callisto, as a good place to live. The surface is a vacuum, sure, but it's got surface ice which probably has liquid water underneath making it (and Ganymede and Europa for the same reason, and Venus 50 km up, and Earth) one of the few places in the solar system you could theoretically go outside with just a breather and no space suit. Plus it's got protection from charged partic…

All these worlds are yours, except Europa. Attempt no landing there.

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

#267

Post by Someone »

CydeWeys wrote: post #241
btkramer9 wrote: post #232

Earlier quoted context omitted.

This is mostly true on Mars too except perhaps the eternal light part

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.

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

#268

Post by tantalor »

shawabawa3 wrote: post #225
athenot wrote: post #213

Earlier quoted context omitted.

Normal body temperature was defined† in Celsius, at 37ºC; this explains the decimal when used in Fahrenheit (98.6F). So even that argument of convenience doesn't hold. † Yes everyone's baseline temperature is slightly different, but that just makes the decimal on the Fahrenheit scale look even sillier. And fever definitions are also keyed off of Celsius: 37º to 38º is "low grade". Sure, it's an arbitrary convention b…

Whether it's off by a degree or 2 doesn't matter (as you said body temperature varies) But why is 100 ~= body temperature more useful than 100 = boiling water? Why is 50 being kind of cold more useful than 10? I don't get this "Fahrenheit numbers are more useful/convenient/understandable" argument

As a human person, temperature relative to my body is more useful than the boiling point of water at ~100 kpa.

Anyways, in Titan's atmosphere water boils at ~110 C, so much for "100 = boiling water".

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

#269

Post by WalterBright »

mark-r wrote: post #211
tantalor wrote: post #120

Earlier quoted context omitted.

> slowly turn your solar array Sure that's nice but the angle of sunlight is very low so you are limited in that respect, e.g,. available surface area.

There's no atmospheric absorption though, so that would compensate a bit. Building very tall structures would be easy in the low gravity, and you wouldn't need to worry about earthquakes or storms.

I'd often though that a rail or even cable should be strung to the top of Mt Everest, you'd make a fortune off of it shuttling tourists up and down all day.

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

#270

Post by btkramer9 »

svaigsq wrote: post #263
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

If Mars has atmosphere, then Moon has equally useless atmosphere, too. Despite differences in day length, Moon can gather more solar power, than Mars and energy is everything. Besides, those sattellites are gonna crash.

I don't think your atmosphere comparison is valid. The moon has absolutely no atmosphere. Mars' is 1% of earth. That's still a lot of _something_. aerobraking, and easy access to unlimited CO2 is incredibly valuable. Delta-v to mars is less than the moon so the extra solar panels required is not that big of an issue. The moon will probably only be a research outpost because of its gravity and slow rotation. Mars on the other hand will most likely transition to nuclear eventually to sustain a city/colony and industry
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