Talk-Polywell.org

Since the topic came up, I decided to open a new thread for this in order to avoid to much of a topic drift on the other one.
So what would be needed and technological solution could be imagined for terraforming venus?

Here is the wikipedia article on the planet:
http://en.wikipedia.org/wiki/Venus
Challenges that is see:
1. No water (most likely anyway)
2. very dense CO2 atmosphere (96.5% carbon dioxide, with most of the remaining 3.5% being nitrogen)
3. High atmospheric pressure (92 times that of earth).
4. Clouds of sulfuric acid
5. no magnetic field
6. surface temperatures of over 460 °C (860 °F)

I would add three:

7. An orbit too close to the Sun, which drives the sixth challenge.

8. No substantial moon; might have something to do with the fifth challenge.

9. "A Venusian sidereal day thus lasts longer than a Venusian year (243 versus 224.7 Earth days)." (from Venus' Wiki entry)

I think Venus is going to be tougher than Mars to terraform, but also probably a better payoff with gravity closer to Earth's. I am trying to remember which Larry Niven novel describes using one of the gas giants as a fusion-powered gravitational attractor to move the rocky planets into positions more congenial to our purposes.

Skipjack wrote:Since the topic came up, I decided to open a new thread for this in order to avoid to much of a topic drift on the other one.
So what would be needed and technological solution could be imagined for terraforming venus?

Here is the wikipedia article on the planet:
http://en.wikipedia.org/wiki/Venus
Challenges that is see:
1. No water (most likely anyway)
2. very dense CO2 atmosphere (96.5% carbon dioxide, with most of the remaining 3.5% being nitrogen)
3. High atmospheric pressure (92 times that of earth).
4. Clouds of sulfuric acid
5. no magnetic field
6. surface temperatures of over 460 °C (860 °F)

None. (Barring a major physics breakthrough.)

Yeah, I have been kinda critical of it too. It does seem like to big an endeavour.
But there are also some advantages to that planet over Mars. It is really unfortunate. Mars is lacking some of the things that Venus has to much of

Well, if we ever get lucky enough to have fusion powered engines, we can play cosmic billiards with the Oorth cloud to dump water on the Venetian surface, and maybe bind up the CO2 and impart spin.

Ceres and Vesta might have something to offer in a home away from home, if we can tunnel inside them a little.

Yes, results from the Ceres probe ought to be interesting. Was anyone following Cassini's initial Iapetus rendez vous? What it found was totally unexpected.

Wikipedia

Venus has an extremely dense atmosphere, which consists mainly of carbon dioxide and a small amount of nitrogen. The atmospheric mass is 93 times that of Earth's atmosphere while the pressure at the planet's surface is about 92 times that at Earth's surface—a pressure equivalent to that at a depth of nearly 1 kilometer under Earth's oceans. The density at the surface is 65 kg/m³ (6.5% that of water).

We can make things that float under the ocean's surface, so can we make habitats that float in the Venusian atmosphere? The internal pressure of the habitat would necessarily be about one Earth atmosphere, same as a submarine. Of course the high temperature would be a problem except at high altitude.

Zeppelin cities of Venus... I can see come potential there.

A quick google search found http://www.datasync.com/~rsf1/vel/1918vpt.htm

Reading the graphs, you'd want your Zeppelin city flying above 53 km for a comfortable temperature. Probably easier to keep the habitat warmer than ambient. Pressure at those altitudes would allow comfortable breathing with a high O2 content atmosphere. The one big problem I see is the sulfuric acid clouds extending well above and below this zone of favorable temperature and pressure.

Problem are the clouds of sulfuric acid...
They will turn your Zeppelin into mudd real quick.

choff wrote:Well, if we ever get lucky enough to have fusion powered engines, we can play cosmic billiards with the Oorth cloud to dump water on the Venetian surface, and maybe bind up the CO2 and impart spin.

Ceres and Vesta might have something to offer in a home away from home, if we can tunnel inside them a little.

If you can move stuff around that well in the Oort cloud, you'd be at beginning parity with all the other singularities out there. You won't be looking back to the gravity well of your origin. You'd be to worried about being devoured by a more advanced singularity, for your metal, Uranium and Thorium structures and stockpiles, and so, remain very quiet while you "breed" (fork?) and assemble your very quiet (invisible) child Oort world civilizations.

The fact that we on Earth aren't bothered by them is because we're too far deep into the gravity well. We can use that fact as evidence that "power" available to singularities is not infinite; It appears that there are Physical limitations to the physics of energy available to any civilization. Perhaps that is Fission. Perhaps Fusion. Perhaps not infinite energy from the void. No "planet mass" wormholes. They don't bother us because they could only get a few tonnes out of the Solar gravity well and only with great energy expenditure even from the perspective of an advanced Oort cloud singularity.

Want proof? Aren't the Oort cloud civilizations *very* *very* quiet with respect to SETI?

If on Venus, better would be to create floating city's high in the atmosphere. The air is so dense that floating would be easy, this also takes care of the temperature problem. Could use remote robotics to mine the surface for materials.

Only issue is you'd have to make the entire skin of the habitat out of material resistant to sulfuric acid clouds. Seeing as we handle sulfuric acid regularly these days this shouldn't be too much of a challenge. The real challenge would be to get supplies to and from this floating city. There is no ground for a heavy space craft to land on and no ground to use as a launch surface. Practically requires development of thrusters capable of creating a large force without using mass.

Helius wrote:

choff wrote:Well, if we ever get lucky enough to have fusion powered engines, we can play cosmic billiards with the Oorth cloud to dump water on the Venetian surface, and maybe bind up the CO2 and impart spin.

Ceres and Vesta might have something to offer in a home away from home, if we can tunnel inside them a little.

If you can move stuff around that well in the Oort cloud, you'd be at beginning parity with all the other singularities out there. You won't be looking back to the gravity well of your origin. You'd be to worried about being devoured by a more advanced singularity, for your metal, Uranium and Thorium structures and stockpiles, and so, remain very quiet while you "breed" (fork?) and assemble your very quiet (invisible) child Oort world civilizations.

The fact that we on Earth aren't bothered by them is because we're too far deep into the gravity well. We can use that fact as evidence that "power" available to singularities is not infinite; It appears that there are Physical limitations to the physics of energy available to any civilization. Perhaps that is Fission. Perhaps Fusion. Perhaps not infinite energy from the void. No "planet mass" wormholes. They don't bother us because they could only get a few tonnes out of the Solar gravity well and only with great energy expenditure even from the perspective of an advanced Oort cloud singularity.

Want proof? Aren't the Oort cloud civilizations *very* *very* quiet with respect to SETI?

No problem, we provide the singularities with free passage to sunny new homes on the surface of Venus.

Also from Wikipedia: http://en.wikipedia.org/wiki/Terraformi ... uestration

Introduction of hydrogen

Bombarding Venus with hydrogen and reacting it with carbon dioxide, could produce elemental carbon (graphite) and water by the Bosch reaction. It would take about 4×1019 kg of hydrogen to convert the whole Venerian atmosphere. (Loss of hydrogen due to the solar wind is unlikely to be significant on the timescale of terraforming.) Due to the relatively flat surface, this water would cover about 80% of the surface compared to 70% for Earth, even though it would amount to only roughly 10% of the water found on Earth.[4]

The remaining atmosphere, at around 3 bars (about three times that of Earth), will mainly be composed of nitrogen, some of which will dissolve into the new oceans of water, reducing atmospheric pressure further, in accordance with Henry's law.
Capture in carbonates
Bombardment of Venus with refined magnesium and calcium metal could sequester carbon dioxide in the form of calcium and magnesium carbonates. About 8×1020 kg of calcium or 5×1020 kg of magnesium would be required, which would entail a great deal of mining and mineral refining.[8] 8×1020 kg is a few times the mass of the asteroid 4 Vesta (more than 300 miles in diameter).
Modelling by Mark Bullock[9] of Venus' atmospheric evolution suggests that existing surface minerals, particularly calcium and magnesium oxides, could serve as a sink of carbon dioxide and sulphur dioxide. If these could be exposed to the atmosphere then the planet would cool and its atmospheric pressure decline somewhat. One of the possible end states modelled by Bullock was a 43 bar atmosphere and 400 K surface temperature.

Especially like the idea of introducing hydrogen to make Venus have all that water, reminds me of Ray Bradbury's raining Venus. Sure you could find that much hydrogen already frozen in the Oort cloud somewhere. Decent nuclear pulse rockets could move it to...we would get to bomb Venus with "hydrogen bombs"!

If you have the tech to move mass around the solar system, why limit it to hydrogen bombs and mineral rain?

Grab something massive like Mercury, speed it up to smack Venus hard and right where you want it. If you do it right, Venus gets a moon, spins up so it has reasonable day lengths and a magnetic field, you strip some atmosphere away, and what's left will be inundated with enough dirt and minor impacts for several decades to keep it cool enough to finish terraforming.

Great!
Unhhh, what about the "scratch shot"? Earth-ball, corner pocket!