Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

Humans Will Never Colonize Mars

gizmodo.com

Post reply on HN
Print view View original

41–50 of 138 posts

Re: Humans Will Never Colonize Mars

#41

Post by Mikeb85 »

adamsb6 wrote: post #32

One possible motive for large numbers of people to colonize Mars: escaping the control of Earth governments. It’s like seasteading except that when you get up to something the governments really don’t like the cost of intervening is extraordinarily high. On Mars we can build our society of genetically engineered supermen that engage in plural marriage, ritual funerary cannabilism, and telekinesis.

Only problem is that the only entities that will be able to colonize Mars as well as project power will be those same Earth governments.

Re: Humans Will Never Colonize Mars

#42

Post by Syssiphus »

b_tterc_p wrote: post #34
ashtonbaker wrote: post #8

> Air pressure on Mars is very low; at 600 Pascals, it’s only about 0.6 percent that of Earth. > The thin atmosphere also means that heat cannot be retained at the surface. > Once temperatures get below the -40 degrees F/C mark, people who aren’t properly dressed for the occasion can expect hypothermia to set in within about five to seven minutes. Such a thin atmosphere will not transfer heat as effectively as it doe…

help me wrap my head around that. If you’re in -40 in a low pressure atmosphere, it doesn’t cool you down faster because there’s less mass for your heat to transfer to? Does that mean things don’t cool down in a vacuum? Is there a weird curve where by at some point having less cold gas arounds you means you’ll cool down faster instead of slower?

I think that property of a vacuum is already used in a day-to-day object.

https://en.wikipedia.org/wiki/Vacuum_flask

Re: Humans Will Never Colonize Mars

#43

Post by colordrops »

b_tterc_p wrote: post #34
ashtonbaker wrote: post #8

> Air pressure on Mars is very low; at 600 Pascals, it’s only about 0.6 percent that of Earth. > The thin atmosphere also means that heat cannot be retained at the surface. > Once temperatures get below the -40 degrees F/C mark, people who aren’t properly dressed for the occasion can expect hypothermia to set in within about five to seven minutes. Such a thin atmosphere will not transfer heat as effectively as it doe…

help me wrap my head around that. If you’re in -40 in a low pressure atmosphere, it doesn’t cool you down faster because there’s less mass for your heat to transfer to? Does that mean things don’t cool down in a vacuum? Is there a weird curve where by at some point having less cold gas arounds you means you’ll cool down faster instead of slower?

That is correct, things don't cool down easily in a vacuum. Overheating is a problem on space vehicles. Thermal drinking bottles use a vacuum layer to keep heat in.

Re: Humans Will Never Colonize Mars

#44

Post by nolok »

mr_crankypants wrote: post #35
nolok wrote: post #7

The way I see it, there are two goals to human space travels. The first, very distant one, is to seed ourselves among the stars to avoid being erased from existence by anything that would threaten our existence on earth, from man made cataclysm to natural event. The second, with much more immediate result on a human scale, is that every time we face such a challenge it's only an opportunity for us to develop a new te…

I honestly think that both of those are weak reasons. The first is a problem for other generations; on our own time scale we should focus on the problems that affect us on our own time scale. The second is just not compelling; space exploration is hardly the only endeavor that produces spinoff technology, and it's far from certain that it's the best or most productive way to do so. There has only ever been one goal t…

Challenge ? For the individual and its patrons, sure.

The country or company ? Its lured by the competition and wanting to be the one winning the prize.

But as a society ? When the inevitable "why fund space travel / fundamental physics / ..." question is asked ? Side gains is where it's at.

Re: Humans Will Never Colonize Mars

#45

Post by dsfyu404ed »

b_tterc_p wrote: post #34
ashtonbaker wrote: post #8

> Air pressure on Mars is very low; at 600 Pascals, it’s only about 0.6 percent that of Earth. > The thin atmosphere also means that heat cannot be retained at the surface. > Once temperatures get below the -40 degrees F/C mark, people who aren’t properly dressed for the occasion can expect hypothermia to set in within about five to seven minutes. Such a thin atmosphere will not transfer heat as effectively as it doe…

help me wrap my head around that. If you’re in -40 in a low pressure atmosphere, it doesn’t cool you down faster because there’s less mass for your heat to transfer to? Does that mean things don’t cool down in a vacuum? Is there a weird curve where by at some point having less cold gas arounds you means you’ll cool down faster instead of slower?

You lose/gain heat through conduction and radiation. Eliminating/reducing the atmosphere or making it out of something less conductive or lower specific heat reduces the speed at which the vibrating molecules of your body transfer kinetic energy to or gain energy from the molecules of the surrounding environment.

The vast majority of heating/cooling that people experience in their day to day lives is done through conduction from the earth's atmosphere so in most situations you'd lose heat more slowly on Mars even if it is colder. It's kind of like the difference between being in cold air and cold water.

Re: Humans Will Never Colonize Mars

#46

Post by jpm_sd »

This is a really well-written, thorough article. Here's another way to think about it:

Before we try to colonize Mars, we should try colonizing Canada. It's warmer than Mars! It has air and water, so it should be easy! And yet:

https://en.wikipedia.org/wiki/Population_of_Canada#/media/Fi...

Re: Humans Will Never Colonize Mars

#47

Post by jandrese »

b_tterc_p wrote: post #34
ashtonbaker wrote: post #8

> Air pressure on Mars is very low; at 600 Pascals, it’s only about 0.6 percent that of Earth. > The thin atmosphere also means that heat cannot be retained at the surface. > Once temperatures get below the -40 degrees F/C mark, people who aren’t properly dressed for the occasion can expect hypothermia to set in within about five to seven minutes. Such a thin atmosphere will not transfer heat as effectively as it doe…

help me wrap my head around that. If you’re in -40 in a low pressure atmosphere, it doesn’t cool you down faster because there’s less mass for your heat to transfer to? Does that mean things don’t cool down in a vacuum? Is there a weird curve where by at some point having less cold gas arounds you means you’ll cool down faster instead of slower?

You lose out on convection and your heat loss has to be almost entirely through black body radiation instead. Astronauts have to work harder to stay cool than to stay warm, especially if the sun is shining on them.

Re: Humans Will Never Colonize Mars

#48

Post by nolok »

AnIdiotOnTheNet wrote: post #39
nolok wrote: post #7

The way I see it, there are two goals to human space travels. The first, very distant one, is to seed ourselves among the stars to avoid being erased from existence by anything that would threaten our existence on earth, from man made cataclysm to natural event. The second, with much more immediate result on a human scale, is that every time we face such a challenge it's only an opportunity for us to develop a new te…

I can get behind that, but really we ought to colonize Antarctica first (as in, with a self-sustaining colony). It's a much easier target and still presents significant challenges.

Sadly what I know of humanity tells me that we won't do that without ruining it to drill for resources like oil, so I say let's leave at least one place untouched back here on earth until we have a backup plan somewhere.

Re: Humans Will Never Colonize Mars

#49

Post by Symmetry »

b_tterc_p wrote: post #34
ashtonbaker wrote: post #8

> Air pressure on Mars is very low; at 600 Pascals, it’s only about 0.6 percent that of Earth. > The thin atmosphere also means that heat cannot be retained at the surface. > Once temperatures get below the -40 degrees F/C mark, people who aren’t properly dressed for the occasion can expect hypothermia to set in within about five to seven minutes. Such a thin atmosphere will not transfer heat as effectively as it doe…

help me wrap my head around that. If you’re in -40 in a low pressure atmosphere, it doesn’t cool you down faster because there’s less mass for your heat to transfer to? Does that mean things don’t cool down in a vacuum? Is there a weird curve where by at some point having less cold gas arounds you means you’ll cool down faster instead of slower?

Vacuums make very good insulators, that's how a thermos works. Any cool gas is cooling you down but the denser it is the faster you cool down.
Post reply on HN