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Mars will never be able to be a "second home" for humanity: it lacks the ability to maintain an atmosphere that can support humans due to its weak magnetic fiel

Mars will never be able to be a "second home" for humanity: it lacks the ability to maintain an atmosphere that can support humans due to its weak magnetic field. The bottom of the ocean would be far more habitable if we faced any type of extinction event.

bjelkeman-again 7y ago
It may be possible to create a magnetic field to protect the atmosphere. https://en.m.wikipedia.org/wiki/Terraforming_of_Mars#Protecting_the_atmosphere https://en.m.wikipedia.org/wiki/Terraforming_of_Mars#Protect...
ourlordcaffeine 7y ago
Without the magnetic field, a thick atmosphere on Mars will still persist for tens of thousands of years.
- fucking_tragedy 7y ago
  It took billions of years for atmospheric oxygen to accumulate on Earth.
  - CydeWeys 7y ago
    Yeah, but most of that was waiting around for oxygen-releasing life to evolve. We could create an oxygen atmosphere on Mars much more quickly than that, because we'd be sending life explicitly for that purpose that's ready now, and we'd also be importing gases and digging up in-situ resources and turning them into gas.
    - fucking_tragedy 7y ago
      > Yeah, but most of that was waiting around for oxygen-releasing life to evolve. No, it wasn't. Photosynthesis that released O2 evolved relatively quickly, and was more efficient than other forms of photosynthesis. Then it took another billion years for oxygen to accumulate in the atmosphere. Mind you, we had an entire planet with oceans teeming with photosynthetic life. That will be next to impossible to replicate on Mars. There are two oxygen sinks on Earth that reacted with oxygen released from photosynthesis: the first was the ocean, the other was minerals on land. This is the reason that it took so long for atmospheric oxygen to accumulate. Mars will have a lot of oxidizable minerals and compounds that will react with oxygen before it can accumulate in its atmosphere. Even then, it will escape into space without a sufficient magnetosphere to trap an atmosphere.
xvilka 7y ago
The bottom of European ocean?
- fucking_tragedy 7y ago
  The bottom of the ocean on Earth.
CydeWeys 7y ago
The lack of a magnetic field ablates away an atmosphere only on cosmic timescales, not human ones. That seems like a problem that could be solved with the benefit of thousands more years of technological development. Never say never. Just a hundred years ago many people argued it was impossible to ever leave the atmosphere of this planet (And it wasn't ... using cannon. The rocket solved that problem).
- fucking_tragedy 7y ago
  It's a moral hazard to hold out hope for a "home away from home". Terraforming Mars is a moonshot. If we ever find ourselves in a situation where we cannot survive on a planet where food literally grows out of the ground, with abundant liquid water and atmospheric oxygen at 1 atm, how on Earth would we survive on a planet that is devoid of life, has no liquid water, an atmosphere that's 1% the pressure of Earth's with no atmospheric oxygen, and little to no sources of energy? Again, the bottom of the ocean is far more habitable than Mars, even if we experienced a similar extinction event similar to the one we experienced 65 million years ago.
  - stallmanite 7y ago
    What about impacts such as the one that created the moon? We can argue about likelihood of it happening again but large enough impacts can liquify even crust on the opposite side of the planet. The bottom of the ocean won’t help at that point right?
    - fucking_tragedy 7y ago
      I mean, the likelihood is pretty important here. The likelihood of such a large impact was pretty high in the early solar system, and it was high for Mars, as well.
  - CydeWeys 7y ago
    That is a different point though. Earth is habitable now. There are plenty of plausible non-anthropogenic disasters that may make that so not so. Some typical examples include megavolcano eruption, coronal mass ejection, and asteroid impact. It would be good to not have all of our eggs in one basket here on Earth. And it's for exactly the same reason of having redundancy that it would be a good thing for Earth to continue to remain habitable, i.e. we should stop ruining the planet through climate change. It's not a moral hazard at all; the two outlooks are congruous.
thirstywhimbrel 7y ago
> The bottom of the ocean would be far more habitable if we faced any type of extinction event. Yeah, space has a coolness factor, and there are things about the origin of the universe we can't learn from the bottom of the ocean, but an underwater station is one of the most underrated projects humanity could pursue. Oceans are phenomenal shields against radiation, extreme weather, or even the temporary combustion of the atmosphere, should things get that bad. The opportunity to learn about groups surviving in isolated habitats, or about megastructures that have to survive hostile external environments, could even provide really useful lessons for space.

bjelkeman-again 7y ago

It may be possible to create a magnetic field to protect the atmosphere. https://en.m.wikipedia.org/wiki/Terraforming_of_Mars#Protecting_the_atmosphere https://en.m.wikipedia.org/wiki/Terraforming_of_Mars#Protect...

ourlordcaffeine 7y ago

Without the magnetic field, a thick atmosphere on Mars will still persist for tens of thousands of years.

fucking_tragedy 7y ago
It took billions of years for atmospheric oxygen to accumulate on Earth.
- CydeWeys 7y ago
  Yeah, but most of that was waiting around for oxygen-releasing life to evolve. We could create an oxygen atmosphere on Mars much more quickly than that, because we'd be sending life explicitly for that purpose that's ready now, and we'd also be importing gases and digging up in-situ resources and turning them into gas.
  - fucking_tragedy 7y ago
    > Yeah, but most of that was waiting around for oxygen-releasing life to evolve. No, it wasn't. Photosynthesis that released O2 evolved relatively quickly, and was more efficient than other forms of photosynthesis. Then it took another billion years for oxygen to accumulate in the atmosphere. Mind you, we had an entire planet with oceans teeming with photosynthetic life. That will be next to impossible to replicate on Mars. There are two oxygen sinks on Earth that reacted with oxygen released from photosynthesis: the first was the ocean, the other was minerals on land. This is the reason that it took so long for atmospheric oxygen to accumulate. Mars will have a lot of oxidizable minerals and compounds that will react with oxygen before it can accumulate in its atmosphere. Even then, it will escape into space without a sufficient magnetosphere to trap an atmosphere.

xvilka 7y ago

The bottom of European ocean?

fucking_tragedy 7y ago
The bottom of the ocean on Earth.

CydeWeys 7y ago

The lack of a magnetic field ablates away an atmosphere only on cosmic timescales, not human ones. That seems like a problem that could be solved with the benefit of thousands more years of technological development. Never say never. Just a hundred years ago many people argued it was impossible to ever leave the atmosphere of this planet (And it wasn't ... using cannon. The rocket solved that problem).

fucking_tragedy 7y ago
It's a moral hazard to hold out hope for a "home away from home". Terraforming Mars is a moonshot. If we ever find ourselves in a situation where we cannot survive on a planet where food literally grows out of the ground, with abundant liquid water and atmospheric oxygen at 1 atm, how on Earth would we survive on a planet that is devoid of life, has no liquid water, an atmosphere that's 1% the pressure of Earth's with no atmospheric oxygen, and little to no sources of energy? Again, the bottom of the ocean is far more habitable than Mars, even if we experienced a similar extinction event similar to the one we experienced 65 million years ago.
- stallmanite 7y ago
  What about impacts such as the one that created the moon? We can argue about likelihood of it happening again but large enough impacts can liquify even crust on the opposite side of the planet. The bottom of the ocean won’t help at that point right?
  - fucking_tragedy 7y ago
    I mean, the likelihood is pretty important here. The likelihood of such a large impact was pretty high in the early solar system, and it was high for Mars, as well.
- CydeWeys 7y ago
  That is a different point though. Earth is habitable now. There are plenty of plausible non-anthropogenic disasters that may make that so not so. Some typical examples include megavolcano eruption, coronal mass ejection, and asteroid impact. It would be good to not have all of our eggs in one basket here on Earth. And it's for exactly the same reason of having redundancy that it would be a good thing for Earth to continue to remain habitable, i.e. we should stop ruining the planet through climate change. It's not a moral hazard at all; the two outlooks are congruous.

thirstywhimbrel 7y ago

> The bottom of the ocean would be far more habitable if we faced any type of extinction event. Yeah, space has a coolness factor, and there are things about the origin of the universe we can't learn from the bottom of the ocean, but an underwater station is one of the most underrated projects humanity could pursue. Oceans are phenomenal shields against radiation, extreme weather, or even the temporary combustion of the atmosphere, should things get that bad. The opportunity to learn about groups surviving in isolated habitats, or about megastructures that have to survive hostile external environments, could even provide really useful lessons for space.