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Venus could have been habitable for billions of years (2019)

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Re: Venus could have been habitable for billions of years (2019)

#121

Post by Chris2048 »

HPsquared wrote: post #114
Chris2048 wrote: post #97

Earlier quoted context omitted.

But the outer planets have excesses of hydrogen, so round trips could help there? The upside is, of water aka H2O that we need, the 2 H atoms are the lighter component, specifically: 2H = 2 * 1.67 * 10(-24) grams 1O = 1 * 2.65 * 10(-23) grams So hydrogen is 11% of water, and oxygen is 88%; meaning every kg hydrogen can combine with 8kg oxygen to give 9L water. So all the Oxygen already being there (in CO2) is good.

If we were capable of planetary-scale transportation of materials, we wouldn't really need to live on planets anyway - it'd be a rather moot point.

Space stations would also be practical, yes, but I'm not sure how desirable they'd be (for long-term habitation). Also, we don't really know the long-term effects of low gravity, whereas earth and Venus have similar gravity wells.

Re: Venus could have been habitable for billions of years (2019)

#122

Post by jamiek88 »

debo_ wrote: post #38
eggsome wrote: post #25

Earlier quoted context omitted.

Surely it would cool below the point where Co2 becomes solid (most of the atmosphere is Co2). Imagine walking around on fields of Co2 :)

Reminds me of the short story "A Pail of Air".

I read that short story as a kid and tried to remember the title for years, you’ve just scratched that itch!

Re: Venus could have been habitable for billions of years (2019)

#123

Post by thaumasiotes »

cambalache wrote: post #79
cookiengineer wrote: post #77

Earlier quoted context omitted.

They are called brown dwarfs... but it's better to link the NASA backyard worlds project directly for the curious: https://www.zooniverse.org/projects/marckuchner/backyard-wor...

I suspected so. But all those objects are in this solar system.Brown dwarfs are sub-stellar bodies.

I find it kind of weird to have a different word for the same object depending on where it is. As I understand it, Jupiter would be a brown dwarf except that the presence of the Sun disqualifies it.

Re: Venus could have been habitable for billions of years (2019)

#124

Post by ramraj07 »

ReaLNero wrote: post #105
ramraj07 wrote: post #74

Earlier quoted context omitted.

My working hypothesis is that the galaxy (if not at least the solar system) is teeming with rocks containing Protozoa that are ready to colonise any planet with the right conditions (in a matter of thousands of years after the conditions are right) the moment they are ready. Perfectly explains everything we see and honestly would not be surprising at all. We need to start developing meaningful working hypotheses and…

Wow, that's... actually pretty sensical. The science part of me rejects it for having no evidence. But the pragmatic part of me would put its money underneath the theory. The reason The bigger question is: how did the first Protozoa form? The usual primordial soup theory of random chance? One good thing about this theory is that if there are 10^7 habitable planets at any given moment, each of them are "trying to prod…

If we work under this assumption, then I’d expect all the living material out there to be of the same chemistry and origin - again unproven conjecture but I’ll be surprised if two life forms of completely different chemistries can compete on comparable levels in the same environment - one will probably always be more efficient than other due to fundamental limits on the chemistry of their constituent molecules; I feel like new life of any chemistry can only form in a sterile environment since pre existing life seems to find ways to harness all available energy in any environment quite soon. Thus if we have life of a particular form floating ready to contaminate any new planet, then it’s possible that life of no other form can form in that galactic neighbourhood!

So the Star Trek episode where they discover why all the species around the galaxy all have DNA based genetics is probably on the money if you ask me!

Re: Venus could have been habitable for billions of years (2019)

#125

Post by thaumasiotes »

protoman3000 wrote: post #117

I recently learned about the estimated age of the universe. It’s only 13.8 billion years. So when it says Venus was hospitable for billions of years, let’s say 2 billion years, that amounts already to 14% of all there was and will ever be. What marvel did happen in this time?

> So when it says Venus was hospitable for billions of years, let’s say 2 billion years, that amounts already to 14% of all there was and will ever be.

Huh? You're saying the universe is about to end?

Re: Venus could have been habitable for billions of years (2019)

#126

Post by scatters »

k3liutZu wrote: post #100
chii wrote: post #87

Earlier quoted context omitted.

we are terraforming the earth - see how much co2 is being pumped out!

Since we're trying to move _away_ from "terra", should we call the current state maybe "marsforming"?

We're going towards Venus rather than Mars, though. So "veneraforming".

Re: Venus could have been habitable for billions of years (2019)

#127

Post by Chris2048 »

nkingsy wrote: post #118
Chris2048 wrote: post #98

Earlier quoted context omitted.

A solar shield would be a serious space structure. A mega-structure even. We (any/all nations of humanity) don't really have much of a space presence, let alone industry. If we did, I think we'd first build solar array, around earth, to help our energy shortage; I'm not sure we have a space shortage, so Venus doesn't really solve any current problems. Maybe we can find a light gas that could form a thin layer in the…

That would be a very long extension cord

Either stuff could be manufactured in space or, light could be beamed down to the planet; I wasn't thinking of a solar array of photo-voltaic panels, but rather an array of mirrors and something to condense it into a deathray / beam.

The great thing about a solar array in space is it can be in sunlight 100% of the time, without needing to change orientation, and the shadow it casts needn't be on earth (i.e. nothing is deprived of sunlight).

The difficulty is that since the earth spins, and we couldn't beam down to the same location, so maybe we'd need an array of geo-statically orbiting beam relay stations to switch between.

Re: Venus could have been habitable for billions of years (2019)

#128

Post by thaumasiotes »

andrewflnr wrote: post #31
spurgu wrote: post #26

Question I'm asking myself is, what's the likelihood there would have ever been fossil fuel deposits with the potential to kickstart a civilization?

Humans had civilization before we knew how to use fossil fuels, we just didn't have industrial civilization. AIUI civilization mostly consists of agreeing to live and work together in groups bigger than Dunbar's number.

I've seen two pretty common definitions of "civilization". One is agriculture; one is writing.

There have been plenty of "barbarian" groups that coordinated on very large scales.

Re: Venus could have been habitable for billions of years (2019)

#129

Post by onion2k »

01100011 wrote: post #55

And it could be again... I wish we would plan ahead and try a solar shield at L1. If we cooled the planet sufficiently, the CO2 would solidify and we could get to work processing it. Venus is far more interesting than the dusty little rock we keep probing. Sure, it may take a millenium, but the sooner we start, the sooner we finish.

Wouldn't a solar shield get heated up by a force equal to the amount of energy it's providing shielding for minus whatever it can reflect away? That would require some significant cooling even if the shield is 99 9999% reflective. How would you stop it getting too hot and eventually breaking down?

Re: Venus could have been habitable for billions of years (2019)

#130

Post by ddalex »

01100011 wrote: post #55

And it could be again... I wish we would plan ahead and try a solar shield at L1. If we cooled the planet sufficiently, the CO2 would solidify and we could get to work processing it. Venus is far more interesting than the dusty little rock we keep probing. Sure, it may take a millenium, but the sooner we start, the sooner we finish.

I may talk out of my arse, but my understanding is that the majority of the heat is coming from the inner planet core which can't cool to space due to the insulating blanket of CO2, not from illumination from the sun (something like an order of magnitude more)

so nothing will be practically solved with a sun heat shield, we need to find a way to break the CO2 somewhat quickly

but then we have the same challenge here on Earth....

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