Terraforming Venus

[Dientus]

7 minutes ago, Jacke said:

It's going to be over 800 years.  There's no new technology that can cause Venus to radiate heat faster than a black body, that's the physics of the universe as it is.  As Venus is not a black body and it radiates into an interplanetary medium that is warming than absolute zero, it will take longer for it to cool.

I understand that thermal radiation can not transfer faster than Weins displacement law allows, except when the temperature is over about 10 million K, but predicting what the future can or can not overcome is impossible. Flying was impossible at one time, hovercars were supposed to be the norm in 2000, and noone predicted the affects of deep sea ocean currents on the arctic ice.

 

One day we may be able to move a vast amount of an extreme heat absorbing mass at near light speeds using machines of planetary mass and scale to accomplish the impossible. Cutting the cooling time in half or more. Some great new cosmic thermal radiator. Or maybe not. Regardless, I still wonder why Venus or two other better candidates.

[kerbiloid]

1 hour ago, Dientus said:

Flying was impossible at one time

The flying doesn't contradict the thermodynamics.

They need some thermodynamical artifact to turn the Venusian thermal energy into some form of informational entropy-related thing.

Some megacubic-rubic self-shuffling and then jumping away at relativistic speed, taking away all excessive heat energy and relative entropy.

(Ten million years later it hits somebody's galactic black hole, and a whole galaxy explodes).

[Dientus]

9 minutes ago, kerbiloid said:

The flying doesn't contradict the thermodynamics.

They need some thermodynamical artifact to turn the Venusian thermal energy into some form of informational entropy-related thing.

Not trying to change the rate of heat transfer, trying to move the medium that absorbs that heat much faster through longer and larger surface areas. Much much larger and longer. Planet sized larger and longer. Or maybe instantaneously transport the medium, liguid or gas or whatever to a distant larger radiator.

 

Or maybe we can just ALT+F12

Edited July 10, 2021 by Dientus
out of likes again LoL

[StrandedonEarth]

Keep slamming it with iceteroids from the Kuiper belt to simultaneously spin it up and cool it down, while delivering more H₂ it probably needs.

[Jacke]

3 hours ago, StrandedonEarth said:

Keep slamming it with iceteroids from the Kuiper belt to simultaneously spin it up and cool it down, while delivering more H₂ it probably needs.

Welp, considering the low amount of mass in the Inner Solar System Asteroid Belt, I suspect there's not much more mass in the Kuiper Belt.  I think the upper limit, even considering there'd be more ices, would be 10 times the mass of the Asteroid Belt.

My gut feel is even with dropping all of both belts on Venus, there wouldn't be enough mass and thus angular momentum to change the spin of Venus sufficiently or even marginally.

Also, the problem with dumping ices including water ice on Venus is Venus doesn't have a cold trap, which Earth does at about 21km.  Water freezes out there and it's lower than the ozone layer, thus keeping most water protected from the hard ultraviolet that will break water apart, leading to the hydrogen escaping.  Water in Venus's atmosphere will diffuse up until it gets exposed to hard ultraviolet, where it's broken up and the hydrogen lost.

Even avoiding future hydrogen losses, I don't know if there's enough water in the Kuiper Belt to bring the amount of water on Venus up to Earth levels.  The amount that would be absorbed into the crust and how fast is very variable.

Edited July 11, 2021 by Jacke

[kerbiloid]

Imho, only a teleportal to a cold gas giant can help.

Teleport the cold hydrogen from Saturn or Neptune into the Venusian air.
Even if it's getting lost, no problem, the Saturn is big.

So, thousands of gates on the Maxwell Mountains will exhaust cool hydrogen (or first process it with CO2 into water and coal).
Thousands of gates will be floating under balloons in the Saturnian atmosphere.

This also can bring some angular momentum to force the proper rotation.

Cover the whole Venus with water (except the Maxwell Mountains), bring the algae, fishes and other water things.

According to wiki, the total atmosphere mass is 4.8*10²⁰ kg, mostly CO₂.
https://en.wikipedia.org/wiki/Atmosphere_of_Venus

CO₂ = 12 + 2 * 16 = 44, so it's 32/44*4.8*10²⁰ =  3.5*10²⁰ kg of oxygen, which can give 18/16*3.5*10²⁰ = 3.9*10²⁰ kg =  390 mln km³ of water.

The Venusian surface = 460 mln km².

So, an estimated ocean depth = 390/460 ~= 0.85 km ~= 1 km.

Spoiler

The second picture is from

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

As we can see, there will be an equatorial continent, a subarctic continent, and various islands.

 

Centuries later it will be a tropical spa.

The only disadvantage is: first you need to invent the teleportation. But you anyway need it for greater good.

Edited July 11, 2021 by kerbiloid

[sh1pman]

4 hours ago, Jacke said:

Even avoiding future hydrogen losses, I don't know if there's enough water in the Kuiper Belt to bring the amount of water on Venus up to Earth levels. 

Mine Europa for water ice, it has twice as much water as Earth.

[kerbiloid]

The water is a poor option, because the CO2 stays or dissolves and turns the ocean into acid.

Hydrogen is required.

[sh1pman]

Just now, kerbiloid said:

The water is a poor option, because the CO2 stays or dissolves and turns the ocean into acid.

Hydrogen is required.

First remove CO2, then bring water. Use some water to make hydrogen.

[kerbiloid]

Just now, sh1pman said:

First remove CO2, then bring water. Use some water to make hydrogen.

But why remove the precious C when it can be used for local plants.

[sh1pman]

Just now, kerbiloid said:

But why remove the precious C when it can be used for local plants.

Ok, remove CO2 but leave some of it nearby (in orbit). CO2 ice asteroids. Deorbit these asteroids when C is needed for plants.

[Dientus]

Interesting note, about 56 km (35 miles) from the surface, the atmosphere is the most Earth like in the solar system. With the heavier gases sinking, and O and H rising (not breathable still mind you) 

If it wasn't for those high winds, floating cities may be another future viable option. Shame the wind speeds at the surface are low, and the winds higher up are unbelievable instead of the other way around.

Edited July 11, 2021 by Dientus
clarification

[cubinator]

3 hours ago, Dientus said:

If it wasn't for those high winds, floating cities may be another future viable option. Shame the wind speeds at the surface are low, and the winds higher up are unbelievable instead of the other way around.

Why is the wind speed such a problem? You can just ride it on your floating city and then the day/night cycle becomes 4 days long instead of 200+. Already the air is habitable enough in a balloon full of breathable air, as long as adequate acid protection is present.

Edited July 11, 2021 by cubinator

[Dientus]

2 minutes ago, cubinator said:

Why is the wind speed such a problem? You can just ride it on your floating city and then the day/night cycle becomes 4 days long instead of 200+. Already the air is habitable enough in a balloon full of breathable air, as long as adequate acid protection is present.

I  guess it would depend entirely on HOW you were floating, relative speed and all.

If there were a way to make glass balloons strong enough we may have a winner, how do you think floating/flying should be accomplished to combat the obvious? That is, excluding tech that is too sci fi, such as anti-gravity.

[cubinator]

3 minutes ago, Dientus said:

I  guess it would depend entirely on HOW you were floating, relative speed and all.

If there were a way to make glass balloons strong enough we may have a winner, how do you think floating/flying should be accomplished to combat the obvious? That is, excluding tech that is too sci fi, such as anti-gravity.

I'm no balloon expert, but I think certain chemical coatings could do the trick. They do make gloves and lab coats to resist acid, after all. Probably something shaped more or less like a typical balloon, with denser habitation areas and rooms hanging below, and a large, mostly-open common area above. Trees and plants could be planted there for closed-loop life.

Perhaps the balloon could be made to contract or expand to control altitude, although that would require some tremendous strength that could tear it apart if something broke. Of course, venting air to lose altitude is a less than optimal solution. Fins and sails on the outside could control the motion of the city.

[Jacke]

16 hours ago, sh1pman said:

Mine Europa for water ice, it has twice as much water as Earth.

14 hours ago, kerbiloid said:

The water is a poor option, because the CO2 stays or dissolves and turns the ocean into acid.

Hydrogen is required.

14 hours ago, sh1pman said:

First remove CO2, then bring water. Use some water to make hydrogen.

This shows that terraforming is complex.

The actual needed steps to change this are likely complex.  Add water now and it goes into vapour and becomes exposed to extreme ultraviolet and loss of hydrogen.  Venus likely needs to be cooled first, but doing so without changing the whole planet's orbit is likely too hard.  And that cooling is still going to be over 800 years, likely a lot over.

First, even the whole of Europa may not be enough water to leave some on the surface as water will go into the rock.  Second, the shear amount of carbon dioxide is from a dry crust without any water, especially as the crust appears to not have any plate tectonics to recirculate rock to absorb the carbon dioxide.  The lack of plate tectonics may also be due to little water in the crust.

And without moving Venus, it's still close to the Sun.  And due to the Sun getting brighter over its lifetime (as all main sequence stars do, due to the accumulation of helium in the stellar core), the Sun is brighter now that what it was in the past when it drove Venus into a runaway greenhouse effect.

[kerbiloid]

By placing a portal on Jupiter (it's anyway too large), we can produce a jet of teleported hydrogen and put Venus into the Lagrange point on the Earth orbit.

[Admiral Fluffy]

Isaac Arthur suggested nuking Venus to blow away the atmosphere.

[kerbiloid]

Does Isaac Arthur realize how many megatons are in a typical hurricane?

[cubinator]

There is a convenient nuke just 108 million km away.

Also, wouldn't they want to take the atmosphere to put some of it on Mars?