Mars likely to have enough oxygen to support life: study • Hacker News Board

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

#211

Post by cbkeller » Wed, Oct 24, 2018, 1:38 AM UTC

cbkeller wrote: post #133

richardknop wrote: post #97

Earlier quoted context omitted.

What are the current thoughts on what caused oceans on Mars to disappear (with some remainder concentrating in ice caps)? Was it some impact of a really big meteor/comet? It is accepted that Mars used to have liquid water oceans and rivers in the past, correct? You can see geological remains of rivers and oceans, for example, quite clearly on Mars.

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…

oh, forgot about this paper (https://www.nature.com/articles/nature05873) which makes a pretty reasonable argument for paleo-shorelines on the northern basin of the Martian dichotomy. If this is correct then it'd be entirely reasonable to call the body of water responsible an "ocean"

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

#212

Post by njarboe » Wed, Oct 24, 2018, 4:30 AM UTC

coldtea wrote: post #70

njarboe wrote: post #44

Earlier quoted context omitted.

Things I know about Mars: No established legal or social framework. Things I know about Earth: Probability of finding a place to be left alone with a small group of like minded people. 0 A certain type of person is interested in living a life where they have a large amount of control over the political and social systems they live with. The American frontier was an ideal place for such people to move to. Many took ad…

> Probability of finding a place to be left alone with a small group of like minded people. 0 Probability of doing the same on Mars, where even getting there means submitting to all kinds of established legal and social frameworks to be accepted on a mission, and where you'd need to stick close to other members (whatever minded they are) to survive and constantly report back home: below zero. > A certain type of pers…

Maybe the US could designate some areas for "free towns" in northern Nevada and western Oregon (currently almost uninhabited) where all national, state, and county laws (except maybe pollution laws) are not enforced. People there just deal with the local laws and taxes. Would be cool to see how some of these areas would develop.

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

#213

Post by richardknop » Wed, Oct 24, 2018, 8:13 AM UTC

rohit2412 wrote: post #207

richardknop wrote: post #87

Earlier quoted context omitted.

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…

It might though. When ice age ended, whole species went extinct (saber-toothed tigers, mammoths etc). Our species somehow clinged on but the population was decimated to couple of hundred individuals at the worst point. Back then we were hunter gatherers so we were much better at surviving out in the wild.

If something like what happened 10,000 years ago happened today, I'm less optimistic about our ability to survive very long. If we were reduced to couple of hundred people back then when we were used to living in the wild, we might go to 0 this time. There are some small tribes of indigenous people in Amazon rain forrest and couple other places who might be better equipped to survive but that is not guaranteed.

I think you are overestimating resilience of our species, we have not yet been tested by any serious cataclysm since modern civilisation, compared to our ancestors, who were much tougher than us though, and they only barely survived.

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

#214

Post by worldsayshi » Wed, Oct 24, 2018, 3:26 PM UTC

jamesrcole wrote: post #132

worldsayshi wrote: post #107

Earlier quoted context omitted.

The world has gotten much much better in some ways (health, longevity, child-mortality, education, economy, violence). But it has also gotten much much worse in others (environmental destruction, military capability). We can't just focus on one aspect and neglect the other. One doesn't take away the magnitude of the other. The magnitudes of the bad as well as the good are both enormous.

> We can't just focus on one aspect and neglect the other Who is doing that? I said "That's not to say there aren't big issues, or no things that have gotten worse, but there's a clear and very strong overall trend." When you look at the magnitudes it's clear that overall the direction is overwhelmingly in the positive direction. You say it has " gotten much much worse in others (environmental destruction, military c…

> When you look at the magnitudes it's clear that overall the direction is overwhelmingly in the positive direction.

No, we are quickly and increasingly progressing towards depleting all our means for life on Earth. And our current response to that is massively inadequate. This nullifies all other progress.

> and in what other sense could military capabilities be bad

With more military power it becomes easier to oppress and harder to revolt against bad politics. Democracy relies in some part in the potential of people to revolt.

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

#215

Post by rohit2412 » Wed, Oct 24, 2018, 11:57 PM UTC

richardknop wrote: post #82

rohit2412 wrote: post #63

Earlier quoted context omitted.

I doubt outside of gamma ray bursts if anything can actually wipe out all humanity. And even then, a nuclear bunker on the Earth is far more habitable than any non settlement. In fact, I'll argue that any money spent on vanity Mars settlements is going to save more lives in a calamity if it is spent helping developing countries lift people out of poverty. > although I have to think it should be easy enough to see how…

Meteor or comet strike can easily wipe us all out just as it did Dinosaurs. And new science is suggesting impacts such as the one that killed off dinosaurs are more frequent than previously thought. So a big one (not necessarily as big as to completely end life on Earth but with potential to kills hundreds of millions if not billions of people and/or at the very least end our civilisation and set us back hundreds of…

I am not seeing what you mean to say. Will starting a costly Mars settlement dependent on Earth for resources prevent these asteroids? Isn't a self sufficient pod on Earth/space/moon much easier starting point? Isn't a nuclear bunker under the Earth as safe from these calamities as a settlement on Mars itself?

Finally, I don't think a meteor which wiped out dinosaurs will wipe out humans. We can always use a nuclear bunker and save a few hundred humans with years of food to survive on.

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

#216

Post by jamesrcole » Thu, Oct 25, 2018, 2:20 PM UTC

worldsayshi wrote: post #214

jamesrcole wrote: post #132

Earlier quoted context omitted.

> We can't just focus on one aspect and neglect the other Who is doing that? I said "That's not to say there aren't big issues, or no things that have gotten worse, but there's a clear and very strong overall trend." When you look at the magnitudes it's clear that overall the direction is overwhelmingly in the positive direction. You say it has " gotten much much worse in others (environmental destruction, military c…

> When you look at the magnitudes it's clear that overall the direction is overwhelmingly in the positive direction. No, we are quickly and increasingly progressing towards depleting all our means for life on Earth. And our current response to that is massively inadequate. This nullifies all other progress. > and in what other sense could military capabilities be bad With more military power it becomes easier to oppr…

> No, we are quickly and increasingly progressing towards depleting all our means for life on Earth. And our current response to that is massively inadequate. This nullifies all other progress.

All our means for life? That's hyperbole.

It's a serious problem, but it doesn't allow you to pretend that all that progress hasn't happened and hasn't made a difference to people's lives.

> With more military power it becomes easier to oppress and harder to revolt against bad politics. Democracy relies in some part in the potential of people to revolt.

It's unclear what you're referring to. Are you saying there has actually been greater oppression because of greater military power? That this has increased over time?

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

#217

Post by richardknop » Fri, Oct 26, 2018, 3:32 AM UTC

rohit2412 wrote: post #215

richardknop wrote: post #82

Earlier quoted context omitted.

Meteor or comet strike can easily wipe us all out just as it did Dinosaurs. And new science is suggesting impacts such as the one that killed off dinosaurs are more frequent than previously thought. So a big one (not necessarily as big as to completely end life on Earth but with potential to kills hundreds of millions if not billions of people and/or at the very least end our civilisation and set us back hundreds of…

I am not seeing what you mean to say. Will starting a costly Mars settlement dependent on Earth for resources prevent these asteroids? Isn't a self sufficient pod on Earth/space/moon much easier starting point? Isn't a nuclear bunker under the Earth as safe from these calamities as a settlement on Mars itself? Finally, I don't think a meteor which wiped out dinosaurs will wipe out humans. We can always use a nuclear…

Moon has no atmosphere so there is very little protection against cosmic impacts. For Earth, at least, small meteorites burn when falling through upper atmosphere. I am not sure about Mars' atmosphere and how much it protects against impacts.