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Mars likely to have enough oxygen to support life: study

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Re: Mars likely to have enough oxygen to support life: study

#201

Post by anticensor »

stephengillie wrote: post #25
dymk wrote: post #5

Earlier quoted context omitted.

But surely terraforming a barren wasteland is going to be easier than terraforming a (relative) oasis of life! But in all seriousness, the point of colonizing Mars is not to be a replacement for Earth (although redundancy is quite motivating). It's because colonization and population growth has been our MO for the last 200,000 years.

The Anthroposcene is terraforming Earth...into a planet less-suited to support life. Maybe "retro-terraforming" would be more accurate.

Terra-deformation.

Re: Mars likely to have enough oxygen to support life: study

#202

Post by adrianN »

coldtea wrote: post #164
adrianN wrote: post #122

Earlier quoted context omitted.

Nuclear pulse propulsion[1] was deemed doable with 1960's technology and can accelerate several hundred tons of payload enough to reach the nearest stars in a couple of generations. This doesn't require any magic, just lots of money and nukes. [1] https://en.wikipedia.org/wiki/Nuclear_pulse_propulsion

It also requires: 1) the ability to avoid debris at those speeds (which would obliterate the ship) 2) to survive radiation, 3) the nearest stars to be of value life-support wise, 4) a couple of generations to pass, 5) us not to hear back from the mission for years upon arrival, So, a more far-fetched version of solar system exploration, with the next steps even further...

Did you expect it to be easier than solar system exploration or what? The engineering problems have plausible solutions: You'd need a lot of water anyway so a shield of ice can handle debris, the ice, together with the ship's own mass, also shields radiation quite a bit.

This is pretty different from a "fairy tale" and not addressed at all by the blog posts you used as arguments.

Re: Mars likely to have enough oxygen to support life: study

#203

Post by sigstoat »

nradov wrote: post #193
cbkeller wrote: post #133

Earlier quoted context omitted.

It seems increasingly likely that there was originally quite a bit of liquid water on Mars during the Noachian ( https://en.wikipedia.org/wiki/Noachian ) and Hesperian ( https://en.wikipedia.org/wiki/Hesperian ) -- the Martian geological time periods more or less contemporaneous with what we call the Archean Eon on Earth. It's not clear that this would have been quite as extensive as "oceans" yet, but it's definitely…

That's why those schemes for terraforming Mars seem so unrealistic. In order to sustain an atmosphere over the long term we'd have to keep dropping ice comets down the gravity well. There's no way to make it self sustaining.

ugh, mars lost that atmosphere over millions and millions of years.

if we can smack enough comets into it to accomplish anything in the first place, then the maintenance is trivial.

Re: Mars likely to have enough oxygen to support life: study

#204

Post by Balgair »

cbkeller wrote: post #61
gizmo686 wrote: post #26

Earlier quoted context omitted.

The Great Oxygenation Event [0]. Arguably the planet's first mass extinction. To say that nothing we have done to the planet is as bad for the environment as the Great Oxygenation Event would be to pat ourselves on the back for not literally poisoning the atmosphere. [0] https://en.wikipedia.org/wiki/Great_Oxygenation_Event

Geologist here. Yeah, there are a few places you can find microbial survivors of the GOE: https://en.wikipedia.org/wiki/Green_sulfur_bacteria https://en.wikipedia.org/wiki/Purple_sulfur_bacteria Obligate anaerobic photoautotrophs: they photosynthesize, and need light to survive, but don't produce (and are killed by) O2. Unfortunately for them, post-GOE, there aren't many habitats that are anoxic but still have much l…

PBS Eons is a great youtube channel on Earth's biological history. It's very well done stuff. Their 'Purple Earth' video is a good layman's intro to some of the per-oxygenation earth: https://www.youtube.com/watch?v=IIA-k_bBcL0

The early biological history of Earth has a few 'Colored Earth' phases: Red-Purple-Green-White-Blue(hypothetically).

Re: Mars likely to have enough oxygen to support life: study

#205

Post by bufferoverflow »

fuscy wrote: post #99

I never understood why colonizing Mars is needed. Even if a meteorite hits Earth or Yellowstone erupts, Earth would be more "hospitable" to life than any other planet in our solar system because Earth has a lot of resources that are right under our noses: breathable atmosphere, radiation shielding, easily mined metals and organic matter. It's much easier to build and maintain a bio-dome in the Sahara desert, Arctic r…

> Earth would be more "hospitable" to life than any other planet in our solar system because

That's a false statement. A large enough meteor could cause a sterilization event.

Re: Mars likely to have enough oxygen to support life: study

#206

Post by marcosdumay »

coldtea wrote: post #164
adrianN wrote: post #122

Earlier quoted context omitted.

Nuclear pulse propulsion[1] was deemed doable with 1960's technology and can accelerate several hundred tons of payload enough to reach the nearest stars in a couple of generations. This doesn't require any magic, just lots of money and nukes. [1] https://en.wikipedia.org/wiki/Nuclear_pulse_propulsion

It also requires: 1) the ability to avoid debris at those speeds (which would obliterate the ship) 2) to survive radiation, 3) the nearest stars to be of value life-support wise, 4) a couple of generations to pass, 5) us not to hear back from the mission for years upon arrival, So, a more far-fetched version of solar system exploration, with the next steps even further...

Unless you are moving at near light-speed, where a proton is already a problem, debris do mostly not exist in space. If you want to reach one, you'll have to target, and even then it's hard.

Re: Mars likely to have enough oxygen to support life: study

#207

Post by rohit2412 »

richardknop wrote: post #87
rohit2412 wrote: post #59

Earlier quoted context omitted.

1) humans aren't going extinct, given how much we can change our environment to our comfort, human species will survive meteorites and volcanoes. And even if we do, a self sufficient colony in a nuclear bunker or in Antarctica or on the surface of the ocean is likely to survive these events too. Being spacefaring makes no sense for survival, it does for science, but not for survival. projects 2) I would argue that pu…

How do you suggest human species to survive a big impact of meteor or comet? Something like the one in Younger Dryas which ended the ice age (11-12k ago). Tsunamis tall several hundreds of feet wiping out all coastal areas (where most people live as those are most comfortable areas), huge earthquakes and fires that burn down majority of fauna overnight. Then followed by a plunge in temperature that will be the last n…

Yes it will collapse the civilization, without doubt. It will not kill off the entire species as you said, which is what I am arguing.

Does having a settlement on mars change any of that? Should we not first create self sustaining pods on the earth? After that, what do we need mars for? Just for access to water, sunlight, protection from radiation, and gravity? Surely, a settlement on a big spaceship would be viable too?

Re: Mars likely to have enough oxygen to support life: study

#209

Post by rohit2412 »

throwaway8879 wrote: post #64
rohit2412 wrote: post #59

Earlier quoted context omitted.

1) humans aren't going extinct, given how much we can change our environment to our comfort, human species will survive meteorites and volcanoes. And even if we do, a self sufficient colony in a nuclear bunker or in Antarctica or on the surface of the ocean is likely to survive these events too. Being spacefaring makes no sense for survival, it does for science, but not for survival. projects 2) I would argue that pu…

This sounds like a short-lived view to me and the exact kind of sentiment I hear in the climate-change skeptic circles. It is one thing to have a handful of humans survive in an underground bunker somewhere, and a whole different thing to have the species colonize the Galaxy. One is barely surviving and the other is thriving. You cannot deny that our best bet for long-term survival is to get off this planet. Musk is…

I am saying that building a self sustaining pod on earth should be the first step. Not going to mars and establishing a settlement utterly dependent on earth for resources.

And when such pods are built, and self sustaining technology mastered, what use is mars really? Why not make big self sustaining spaceships? What do you really need a planet for?

Re: Mars likely to have enough oxygen to support life: study

#210

Post by v_lisivka »

v_lisivka wrote: post #168
coldtea wrote: post #74

Earlier quoted context omitted.

> Interstellar travel over the next 100-1000 years will be a requirement for the next 5000-10000 years if humans expect to survive that long. Given the mechanics, interstellar travel will most likely always be a pipe dream, because techies still have to believe to some fairy tales... http://www.antipope.org/charlie/blog-static/2007/06/the_high... http://www.antipope.org/charlie/blog-static/2009/11/the_myth...

Hey, we already doing interstellar travel. At some point, we will reach an another star and even another galaxy (Andromeda). Also, there is lot of planet size bodies between us and nearest stars. I expect 10 planets with mass of Jupiter between Solar system and Alpha Centaur system, or 1000 planets with mass of Earth. We can colonize them one by one.

Why??? Why downvoted? What wrong with this site?
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