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

smithsonianmag.com

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

#51

Post by mixmastamyk »

konjin wrote: post #30
whoisthemachine wrote: post #19

It's interesting that multi-cellular life developed on Earth around the same time these scientists hypothesize Venus would have become uninhabitable. Unrelated... still, fun to think about. https://en.wikipedia.org/wiki/Timeline_of_the_evolutionary_h...

Not overly. The Great Oxidation Event nearly destroyed all life on the planet. If it wasn't for a mutation that allowed life to live in an oxygen rich environment Earth could have gone the say way as Venus.

It might also be thought of as a natural consequence, i.e. evolution at work.

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

#52

Post by nojokes »

A lot of CO2 and sulfuric acid is not a problem, it is an opportunity. CO2 means a lot of carbon, and oxygen, sulfuric acid means a lot of sulfur, oxygen and hydrogen.

Oxygen and hydrogen is water. Carbon is life and is solid.

We just need to engineer a process that can use solar energy to convert these substances into some more interesting form. Perhaps some engineered bacteria could do the trick?

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

#53

Post by DoreenMichele »

chrisco255 wrote: post #46
duxup wrote: post #7

Growing up I absorbed all the space stuff I could find. But it wasn't until recently that I realized that the solar system didn't just form into some static natural state where it largely didn't change until say the sun was finished with it's lifespan. Rather it evolves, changes, planets are habitable, then not, moons are formed and break up, even frozen planets are geologically active and are changing, Saturn's ring…

I think it's the way it's presented. We still have a sort of Newtonian "clockwork" view in primary education of astronomy.

The "clockwork" view is objectively incorrect due to being the wrong scale. (Some) Accurate scale models of the solar system get played out across city blocks.

If it's a tinkertoy style model or a drawing within a book, it's made up BS. There are no books large enough to actually show it to scale.

Edit: For the pedants of the world, I have added "(Some)" to my sentence. "Not all accurate scale models" of course. Some are even larger than that.

2nd edit: Folding another comment in here as well that I deleted :

https://en.wikipedia.org/wiki/Solar_System_model

The Sweden solar system scale is listed as 1:20,000,000. Others have used a different scale and been fit into less than an entire country. There are several around the world.

In York, it is spread across 6.4 miles:

https://astrocampus.york.ac.uk/cycle-the-solar-system/

There's another in Greater Boston:

https://foursquare.com/eric_odea/list/museum-of-science-bost...

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

#54

Post by elihu »

stx wrote: post #22
elihu wrote: post #13

I wonder if one were to install a solar shade in front of Venus to block all light from the sun, how long would it take to cool to "normal" temperatures? The Earth cools pretty fast between day/night and seasonally, but Venus has a much thicker atmosphere, almost more like an ocean. And then the ground itself wouldn't cool instantly either. That's a lot of thermal mass.

Would cooling it help to reduce the amount of pressure the atmosphere has? Isn't the pressure on the surface something like 95 times that of earth.

I think the average pressure should stay about the same because the mass stays the same, but if it compresses maybe the pressure goes up in low-lying areas and goes down at higher altitudes.

According to Wikipedia, CO2 can liquify at around 5 atmospheres, though it has to be pretty cold at that pressure. The phase diagram shows it as a liquid around room temperature (300K or so) at about a hundred atmospheres. Which makes a liquid ocean of CO2 is at least sort of plausible if the temperature drops far enough.

https://en.wikipedia.org/wiki/Carbon_dioxide#/media/File:Car...

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

#55

Post by 01100011 »

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.

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

#56

Post by redis_mlc »

duxup wrote: post #7

Growing up I absorbed all the space stuff I could find. But it wasn't until recently that I realized that the solar system didn't just form into some static natural state where it largely didn't change until say the sun was finished with it's lifespan. Rather it evolves, changes, planets are habitable, then not, moons are formed and break up, even frozen planets are geologically active and are changing, Saturn's ring…

> Growing up I absorbed all the space stuff I could find.

Yeah well, when I was growing up Pluto was still a planet.

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

#57

Post by 01100011 »

eggsome wrote: post #25
stx wrote: post #22

Earlier quoted context omitted.

Would cooling it help to reduce the amount of pressure the atmosphere has? Isn't the pressure on the surface something like 95 times that of earth.

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

You beat me to it. Just posted a comment saying the same thing. I think if we solidified the CO2 we would have an easier time dealing with it, but IDK. Then again, we might be able to get to work now by just suspending some blimps in the upper atmosphere. They could use solar energy to sequester the CO2 and start lowering the pressure & temperature.

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

#58

Post by rtx »

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.

Or send some microbes which convert it into oxygen. You are right Mars doesn't have enough resources to support anything.

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

#59

Post by elihu »

herendin2 wrote: post #35
elihu wrote: post #11

Earlier quoted context omitted.

If there was a civilization on Venus anything like our current civilization on Earth, I expect there would still be evidence of it, even in that hostile environment. If nothing else, there'd probably be unnatural formations of ground from mines or freeway construction or whatever.

The oldest known undisturbed area of the Earth's surface is only about 2 million years old It turns over very fast in geological time https://www.livescience.com/3542-oldest-surface-earth-discov...

A fair point. I wasn't thinking about tectonic subduction, which would hide pretty much all evidence that anyone was there. Though I think that article is talking more about having the same surface exposed to the air for a long time, without being worn down by weathering or covered in silt. You could have an area covered in dirt or partly eroded away, and still be recognizably an artifact of civilization for a long time. I don't know if such things would last billions of years though.

Also, I expect weathering and erosion would happen a lot faster on Venus, what with the high heat and extreme winds that are more like a flowing ocean current than what we'd think of as "wind".

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