Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

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

smithsonianmag.com

Post reply on HN
Print view View original

91–100 of 236 posts

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

#91

Post by ncmncm »

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.

Venus is interesting in so many ways.

It did not, so far as we can tell, get blasted by a Mars-sized proto-planet like Earth did, which made the Moon and entirely re-melted Earth, so probably got a good head start on breeding life. But maybe Earth's plate tectonics came from that event, too.

AIUI, our Moon is also the reason we are not tidally -almost- locked to the sun, with a permanent equatorial 250 mph wind.

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

#92

Post by tomerico »

rtx wrote: post #58
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.

The problem is that Venus is missing important ingredients for life. Most notably is the lack of hydrogen.

If you are interested in learning more on hypothetical approached of terraforming Venus, I suggest reading this Wiki article: https://en.wikipedia.org/wiki/Terraforming_of_Venus#Biologic...

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

#93

Post by ncmncm »

chii wrote: post #87
excalibur wrote: post #85

Earlier quoted context omitted.

We can't even terraform the Earth.

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

It is being prepared for species better adapted to high temperatures than us.

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

#95

Post by emtel »

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.

No, and the other comments about gas laws and volume are overthinking it a bit. Pressure at the surface is caused by the weight of the atmosphere. On earth, a column of air extending from sea level to space, with cross sectional area one square inch, weighs 15 pounds.

Neither the temperature or volume of the atmosphere changes its weight. (Ok, I suppose a hotter atmosphere has more volume and extends higher into space and weighs slightly less, as it is farther from the planet on average, but I assume that’s a fairly negligible effect)

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

#96

Post by rajansaini »

MichaelMoser123 wrote: post #86
rtx wrote: post #58

Earlier quoted context omitted.

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

Also Venus is closer (minimum 38.2 million kilometer for Venus vs minimum distance of 55.7 million for Mars). However I don't know about the microbes, i fear that they might get killed at an average temperature of 737 K (464 C). https://nssdc.gsfc.nasa.gov/planetary/factsheet/marsfact.htm... https://nssdc.gsfc.nasa.gov/planetary/factsheet/venusfact.ht...

Hopefully someone can provide more info, but apparently there are some bacteria in geothermal vents near Baja California that seem to be able to handle venus-like conditions. No idea what the details are though

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

#97

Post by Chris2048 »

tomerico wrote: post #92
rtx wrote: post #58

Earlier quoted context omitted.

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

The problem is that Venus is missing important ingredients for life. Most notably is the lack of hydrogen. If you are interested in learning more on hypothetical approached of terraforming Venus, I suggest reading this Wiki article: https://en.wikipedia.org/wiki/Terraforming_of_Venus#Biologic...

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.

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

#98

Post by Chris2048 »

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.

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 upper Venus atmosphere to change its reflective profile?

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

#99

Post by galaxyLogic »

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.

> And it could be again...

It could. On the other hand Earth could become the next Venus, if climate change runs out of control. No?

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

#100

Post by k3liutZu »

chii wrote: post #87
excalibur wrote: post #85

Earlier quoted context omitted.

We can't even terraform the Earth.

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"?
Post reply on HN