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Humans Will Never Colonize Mars

gizmodo.com

91–100 of 138 posts

Re: Humans Will Never Colonize Mars

#91
post #86
post #37

Honestly, I agree with the author. We'll set up a few bases, it'll take decades, and by the time we come close to having the technology to make Mars somewhat inhabitable we'll have discovered a more hospitable planet and have the spaceship tech to get there.

Assuming you are talking about extrasolar planets: Outer space is far less hospitable than mars, and the timeframes involved in getting to even very close stars means living aboard the ships traveling there for an extended period of time.

> timeframes involved in getting to even very close stars means living aboard the ships traveling there for an extended period of time

At our current level of technology. Colonizing Mars is likely 50-100 years away, within that time frame it's very conceivable that we might develop the ability to travel between stars quickly.

Re: Humans Will Never Colonize Mars

#92

Something that this article hints at but seems not to explicitly state: there is near-zero economic incentive for anyone to establish or occupy a colony on Mars, and even if there is some incentive, it is not worth the cost. Just the sum of money required to fly the people there alone would be absolutely staggering, and ironically, would create enough greenhouse gas emissions from the launch vehicles to put our envir…

Getting, say, a million people to escape velocity would not be significant in terms of greenhouse emissions, compared to the ~8 trillion revenue passenger kilometres flown annually (which itself is a tiny fraction of global emissions).

Also, if you assume that those colonists are not coming back, their exodus is likely to be carbon negative for Earth.

Re: Humans Will Never Colonize Mars

#93
> 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.

Okay, but that's the experience in an atmosphere that is 100X thicker than that of Mars. :)

Re: Humans Will Never Colonize Mars

#94
post #89

Earlier quoted context omitted.

Vacuum has no temperature. What you describe is a black body spectrum 'temperature'.

That is why I said that I am not sure about the precise terminology. But it still does not change the fact that an object placed in the vacuum of outer space will eventually reach the temperature of the cosmic microwave background, i.e. the temperature of the electromagnetic radiation filling outer space. Also not that I am not talking about any vacuum, I am specifically talking about vacuum of outer space.

It does not change the fact that vacuum, any vacuum, has no temperature...

Re: Humans Will Never Colonize Mars

#95
post #89

Earlier quoted context omitted.

That is why I said that I am not sure about the precise terminology. But it still does not change the fact that an object placed in the vacuum of outer space will eventually reach the temperature of the cosmic microwave background, i.e. the temperature of the electromagnetic radiation filling outer space. Also not that I am not talking about any vacuum, I am specifically talking about vacuum of outer space.

It does not change the fact that vacuum, any vacuum, has no temperature...

Also no perfect vacuum exists which renders this rather irrelevant for discussing what happens in real situations. I also did some reading to figure out the correct terminology - it is certainly correct to say that a perfect vacuum has no thermodynamic temperature as it is defined by the state of motion of the particles making up the system you want to assign a temperature to, however I am still not convinced that it is wrong to associate a temperature with a vacuum based on the electromagnetic radiation filling it.

Re: Humans Will Never Colonize Mars

#96

Something that this article hints at but seems not to explicitly state: there is near-zero economic incentive for anyone to establish or occupy a colony on Mars, and even if there is some incentive, it is not worth the cost. Just the sum of money required to fly the people there alone would be absolutely staggering, and ironically, would create enough greenhouse gas emissions from the launch vehicles to put our envir…

Getting, say, a million people to escape velocity would not be significant in terms of greenhouse emissions, compared to the ~8 trillion revenue passenger kilometres flown annually (which itself is a tiny fraction of global emissions). Also, if you assume that those colonists are not coming back, their exodus is likely to be carbon negative for Earth.

Excellent points. I want to follow up with some back-of-the-envelope math on this later, if I have time. My intuition was that it takes a whole heck of a lot of fuel to get someone to even LEO velocity. Would love to see how that corresponds with air travel.

Re: Humans Will Never Colonize Mars

#97
post #76

Earlier quoted context omitted.

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…

I honestly think the first one mentioned will become a "primary" reason as soon as the first largish "came from the direction of the sun" doomsday asteroid slams into us, and makes us rethink some of our priorities. Assuming we survive the event - and assuming it isn't "The Killer Event". You know - something largish that takes out 3-4 major cities, and we didn't see until much too late (like the near-space flyby we…

Why does propagating human genetics to a different planet/solar system give human existence meaning?

Re: Humans Will Never Colonize Mars

#98
The author is listing facts about Mars that are pretty basic and well-known in the first two paragraphs and proceeds to talk in generalized terms about how we will never get around these obstacles. These are all basic facts about Mars that the engineers working on these problems know very well. Simply listing these facts as proof that colonizing Mars will never work seems overly pessimistic.

Re: Humans Will Never Colonize Mars

#100
post #95

Earlier quoted context omitted.

It does not change the fact that vacuum, any vacuum, has no temperature...

Also no perfect vacuum exists which renders this rather irrelevant for discussing what happens in real situations. I also did some reading to figure out the correct terminology - it is certainly correct to say that a perfect vacuum has no thermodynamic temperature as it is defined by the state of motion of the particles making up the system you want to assign a temperature to, however I am still not convinced that it…

Yes, vacuum has no temperature.

The energy of any radiation that may be going through a vacuum at a given instant is not a property of the vacuum (and is not an actual temperature).

I'll leave it here as I think I have repeated the same thing enough though I am not sure it has been heard.

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