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#201 2014-05-06 10:04:42

Tom Kalbfus
Banned
Registered: 2006-08-16
Posts: 4,401

Re: Venus

RobertDyck wrote:
karov wrote:

A moon is not necessary at all for habitability.
But Venus CAN have a moon.

I didn't say I want to give Venus a moon. I responded too...

SpaceNut wrote:

the possibility for venus to have a moon is nill...this is due to the retrograde spin and proximity to the sun....

This claimed retrograde sping prevents any moon. That's not true. Planetary spin has no effect on gravitational capture. The only gravitational effect of planetary spin is "frame dragging", an effect of general relativity. And that is so weak that it wouldn't affect planetary capture at all. What I said is planetary spin is caused by accreation events, not the other way around.

I believe the moon Triton orbits Neptune against its spin, Venus would not be so different.

If you can move Mercury, why not also move Venus?. I think I have a use for Mercury, it can be used as a gravitational tug. I think that since Earth is near the inner edge of the Sun's habitable zone, it would be best to move Venus further out from the Sun than Earth, the trick is to move Venus past Earth's orbit without having the planet collide with Earth. One possibility is to have a gravitational interaction between Earth and Venus such that the two planets switch positions, that is the Earth moves little closer to the Sun while the exchange of momentum propels Venus further out. The Earth's Moon could then be used as a gravitational tug to drag the Earth back into its original orbit. Venus would get Mercury as a Moon to do this same job. Since Mercury and the Moon are both Vacuum worlds, it should be fairly simple to attack giant rockets to their surfaces and propel them further out from the Sun. So what we have here Is a gravitational interaction between the Earth-Moon system and the Venus-Mercury System. Once Venus-Mercury gets past the Earth, the rockets on Mercury push mercury and drag Venus further out to a safe distance from the Sun between the Earth and Mars. While doing so, Venus could also evolve a 24-hour day night cycle through gravitational interactions between asteroids and the planet's surface. Leaving some Venusian green house gases will keep the planet balmy despite being further away from the Sun.

Last edited by Tom Kalbfus (2014-05-06 10:16:06)

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#202 2014-05-07 01:27:02

karov
Member
From: Bulgaria
Registered: 2004-06-03
Posts: 953

Re: Venus

Even moving Mercury into orbit of Venus would pose dynamical problems for Earth.
Very hard to calculate/ predict ones.
I suggest to NOT TOUCH Earth.

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#203 2014-05-08 03:29:31

Tom Kalbfus
Banned
Registered: 2006-08-16
Posts: 4,401

Re: Venus

It won't, but Earth and Venus would need to exchange places as Venus slowly spirals away from the Sun. There are two satellites of Saturn that do this all the time. You can't place rockets directly on Earth or Venus, therefore their satellites act as gravitational tugs.

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#204 2014-05-08 09:45:49

Antius
Member
From: Cumbria, UK
Registered: 2007-05-22
Posts: 1,003

Re: Venus

Tom Kalbfus wrote:
SpaceNut wrote:

From what I read from this http://wiki.answers.com/Q/Why_don't_the_planets_Mercury_and_Venus_have_moons is that venus if it had plenty of water would have a difficult time having tidal forces as the possibility for venus to have a moon is nill...this is due to the retrograde spin and proximity to the sun....

For teraforming the atmosphere here is the table to the picture of the content of acid.

  • Height (km) Temp.(°C) Atmospheric pressure(x Earth)
    0               462           92.10
    5               424           66.65
    10             385           47.39
    15             348           33.04
    20             306           22.52
    25             264           14.93
    30             222            9.851
    35             180            5.917
    40             143            3.501
    45             110            1.979
    50               75            1.066
    55               27            0.5314
    60             −10            0.2357

I think between 55 and 60 km would be best, 27 degrees centigrade is a bit too warm, what you really want is 15 degrees centigrade for room temperature. Air pressure would be around 0.4 bar I think, If you breath an atmosphere mixture that is half oxygen and half nitrogen, this shouldn't be too bad.

Interesting figures.  Maybe a Venus cloud settlement could use some sort of 'OTEC' thermo-dynamic engine as a power source.

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#205 2014-05-08 14:31:20

Antius
Member
From: Cumbria, UK
Registered: 2007-05-22
Posts: 1,003

Re: Venus

http://www.daviddarling.info/images/Ven … sphere.jpg

http://www.chemistry-blog.com/wp-conten … ramco2.png

It may be possible to colonise the subsurface of Venus without any terraforming and then incrementally modify the planet to make human colonisation easier.

Looking at the atmospheric pressure-temperature profile provided by Void and the phase diagram for CO2, it would appear that at 55km the temperature of the atmosphere is 300K.  This is actually 4.2K beneath the carbon dioxide critical point.  If the CO2 is compressed to 72.9bar at this temperature, it will liquify.

A cloud city tethered at 55km could liquify CO2 and pump it down to a sub-surface settlement where it would provide cooling.  Each kg of liquid CO2 would absorb 800KJ of heat as it vapourised back into a super-critical fluid at Venus surface temperatures.  The tether would be in the form of an elevator tower.  The core of the tower would contain an elevator, allowing the sub-surface mines to export material to the cloud city, where new construction could then take place.  The tether would be structurally supported by bouyancy provided by nitrogen filled steel outer tanks, especially at lower levels where the atmosphere is dense.

In addition to cooling, the cloud city would provide food, which would be difficult to grow underground.  As population gradually increased in the sky cities, new towers would be lowered to the surface.  Ultimately, much of the Venusian subsurface and cloud space will be colonised.

Travel between cloud cities and orbit would probably use Orion type nuclear pulse vehicles.  As the surface is uninhabitable anyway, the contamination matters not.

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#206 2014-05-09 03:28:19

karov
Member
From: Bulgaria
Registered: 2004-06-03
Posts: 953

Re: Venus

Antius,

Make these "trees" -- which you described above -- with habitable/solar-powered/radiator "canopy" and heat & materials exchanging "stem"/"trunk" and extraction/CO2 injection "roots" ...

... alive and self-reproducing ( SRA - self-replicating automata, - kinda-sorta surface-buoyant macro-life ) and they'll consume the environment in mere decades, simultaneously providing multi-store billions of square miles lush and vast habitat, consisting of interlocked-interconected units...

A jungle of habitats.

In near to present day tech-level it will all take a parachuted/baluted/aerostatic "seed" of dozens or hundreds of tonnes which to grow upwards producing more volume and area, and downwards to drill into the crust.

the trees components could be more or less uniform type of http://en.wikipedia.org/wiki/SpaceShaft -like "cells". Thus buoyancy and static mechanical support will come hand in hand and ALSO the surface to orbit and back ( and interplanetary ) transport system could be seamlessly integrated with surface-to-surface & tree-to-tree modes - like et3.com or more generaly the "electromagnetically assisted gravity train" a-la- Paul Birch.

Eating out the whole atmosphere ( most of it as construction material and/or confined within the structure ) would be kind of "creeping para-terraforming" and while utilizing the atmospheric mass the habitat cannopy would gradually settle on solid surface.

Last edited by karov (2014-05-09 03:35:54)

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#207 2014-05-09 04:49:24

Antius
Member
From: Cumbria, UK
Registered: 2007-05-22
Posts: 1,003

Re: Venus

karov wrote:

Antius,

Make these "trees" -- which you described above -- with habitable/solar-powered/radiator "canopy" and heat & materials exchanging "stem"/"trunk" and extraction/CO2 injection "roots" ...

... alive and self-reproducing ( SRA - self-replicating automata, - kinda-sorta surface-buoyant macro-life ) and they'll consume the environment in mere decades, simultaneously providing multi-store billions of square miles lush and vast habitat, consisting of interlocked-interconected units...

A jungle of habitats.

In near to present day tech-level it will all take a parachuted/baluted/aerostatic "seed" of dozens or hundreds of tonnes which to grow upwards producing more volume and area, and downwards to drill into the crust.

the trees components could be more or less uniform type of http://en.wikipedia.org/wiki/SpaceShaft -like "cells". Thus buoyancy and static mechanical support will come hand in hand and ALSO the surface to orbit and back ( and interplanetary ) transport system could be seamlessly integrated with surface-to-surface & tree-to-tree modes - like et3.com or more generaly the "electromagnetically assisted gravity train" a-la- Paul Birch.

Eating out the whole atmosphere ( most of it as construction material and/or confined within the structure ) would be kind of "creeping para-terraforming" and while utilizing the atmospheric mass the habitat cannopy would gradually settle on solid surface.

Interesting, but how exactly would such a tree grow on the surface of Venus?  The temperature is 800K and there is no water.  Nothing can survive there, far less set down roots.

I was thinking of something a little more near term.  A large Orion would deliver a starting colony to the surface of Venus.  Shortly after landing, the cloud tether would be unreeled.  This would gradually ascend to 55km.  It would contain a large gas cooled fast reactor, which would compress and liquefy the atmosphere using a nuclear gas turbine.  This would be sufficient to compress CO2 at several tonnes per second.  This would descend the tether by gravity and upon reaching the colony at ground level, would be used to provide cooling.  The colonists would then burrow into the ground, using the liquid CO2 to first cool-off the rock and then provide continuous cooling.  At the same time, material that is mined out will ascend the elevator to the cloud ‘city’ where new habitat construction would begin.

In this way, a symbiosis develops between the cloud cities and subsurface colonies; the clouds providing cooling, electric power and food and the sub-surface providing bulk raw materials.  Colonies could be founded in this way in the relatively near term, using existing technologies and without any planetary engineering.

Ultimately, entirely new cities would be constructed beneath the surface of Venus and would raise their own cloud tethers, beginning the process again.

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#208 2014-05-09 07:53:35

karov
Member
From: Bulgaria
Registered: 2004-06-03
Posts: 953

Re: Venus

Antius wrote:

Interesting, but how exactly would such a tree grow on the surface of Venus?  The temperature is 800K and there is no water.  Nothing can survive there, far less set down roots.

I meant purely mechanical ( http://en.wikipedia.org/wiki/Clanking_replicator )"trees", not ( http://en.wikipedia.org/wiki/Tree ) trees. wink

What you describe is like a (mechanical) tree (brings immediatelly such association in mind) - the aerostat is the canopy, the rope is the stem, the city/industrial complex on/under the ground is like roots, the CO2 and other materials running up and down are like plant metabolism... the nuke Orion module is the seed/acorn...

I just let my imagination from this initial association to rush/evolve the "tree" into a "forest"..

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#209 2014-05-09 16:50:37

Spatula
Member
From: Raleigh, NC
Registered: 2007-05-03
Posts: 68

Re: Venus

Tom Kalbfus wrote:

You have to prevent half the light from reaching Venus in the first place. The main problem with Venus and the reason it is such a high pressure oven is because it receives too much energy from the Sun.

It is not necessary to block any light from the planet. It's still in the habitable zone. Blackbody calculations suggest it would have a mean temperature of 30-40 degrees C with an Earthlike atmosphere. (Earth is 16 degrees, for comparison). It would be a warm planet for human standards, but definitely livable.

The issue of rotation is likely a non-issue as well. According to recent models of tidally locked planets orbiting red dwarf stars, which are important places to look in the search for extraterrestrial life, it appears that intense cloud formations dominate the sun-facing side. Similar mechanisms are likely to occur on Venus due to its low spin.

Last edited by Spatula (2014-05-09 16:51:15)

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#210 2014-05-09 21:11:59

Tom Kalbfus
Banned
Registered: 2006-08-16
Posts: 4,401

Re: Venus

If Venus is in the habitable zone, then why isn't it habitable? the calculations for temperature excludes the greenhouse effect. One idea I've got is what happens if we just add water, not necessarily to create oceans, but just enough to saturate its atmosphere? Lets say we crash several comets made mostly of water into Venus, this adds water vapor to the atmosphere, Water vapor is a greenhouse gas, the ground heats up, but what about the upper atmosphere at say 55 km? Air is clear, so the mere fact of light passing through air doesn't heat it up, as air is mostly transparent. Water clouds will reflect light back into space. If we added water to Venus, this would dilute the sulfuric acid. We'd end up with a water cycle where it rains and evaporates without any water ever touching the ground.

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#211 2014-05-09 22:27:16

Spatula
Member
From: Raleigh, NC
Registered: 2007-05-03
Posts: 68

Re: Venus

Tom Kalbfus wrote:

If Venus is in the habitable zone, then why isn't it habitable? the calculations for temperature excludes the greenhouse effect. One idea I've got is what happens if we just add water, not necessarily to create oceans, but just enough to saturate its atmosphere? Lets say we crash several comets made mostly of water into Venus, this adds water vapor to the atmosphere, Water vapor is a greenhouse gas, the ground heats up, but what about the upper atmosphere at say 55 km? Air is clear, so the mere fact of light passing through air doesn't heat it up, as air is mostly transparent. Water clouds will reflect light back into space. If we added water to Venus, this would dilute the sulfuric acid. We'd end up with a water cycle where it rains and evaporates without any water ever touching the ground.

Without the greenhouse effect Venus's surface would be 15 degrees C, assuming it maintained an earth-like albedo. Albedo plays a large role in these calculations as well, because with a lower one (darker than earth), you'd be looking at 50 C average temperatures. Earth's would be somewhere around -15.

As for why Venus is a dead place now, the distance to the Sun is an important factor, but also the failure to sequester atmospheric carbon and methane fast enough. Earth's ability to thrive hinged on its ability to remove the ancient greenhouse gases the planet's atmosphere contained in a timely manner. Earth once had much higher CO2 levels in its atmosphere, and higher average surface temperatures (a billion years ago). With those same conditions at Venus's hotter orbit, the greenhouse effect eventually became strong enough to boil the oceans, which then took ~250 million years to lose their hydrogen to space in their atmospheric form. Earth naturally sequesters atmospheric carbon through plate tectonics, in combination with its oceans. Venus doesn't have plate tectonics; its geology is entirely volcanic and the planet takes 200 million more years to renew its surface than Earth.

There wasn't a natural way for Venus to be a habitable place in its orbit due to its geology. A planet with more active plate tectonics could've been just fine there. And if its atmosphere were converted into an earthlike one through artificial means, it could maintain a stable hydrology.

Last edited by Spatula (2014-05-09 22:32:34)

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#212 2014-05-11 07:16:34

Antius
Member
From: Cumbria, UK
Registered: 2007-05-22
Posts: 1,003

Re: Venus

karov wrote:
Antius wrote:

Interesting, but how exactly would such a tree grow on the surface of Venus?  The temperature is 800K and there is no water.  Nothing can survive there, far less set down roots.

I meant purely mechanical ( http://en.wikipedia.org/wiki/Clanking_replicator )"trees", not ( http://en.wikipedia.org/wiki/Tree ) trees. wink

What you describe is like a (mechanical) tree (brings immediatelly such association in mind) - the aerostat is the canopy, the rope is the stem, the city/industrial complex on/under the ground is like roots, the CO2 and other materials running up and down are like plant metabolism... the nuke Orion module is the seed/acorn...

I just let my imagination from this initial association to rush/evolve the "tree" into a "forest"..

A good analogy.  I guess it went over my head.

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#213 2014-05-25 08:41:31

Tom Kalbfus
Banned
Registered: 2006-08-16
Posts: 4,401

Re: Venus

I think if Venus was removed to 1 AU from the Sun, it would become more Earthlike, it could also b set up to repeatedly exchange orbital positions with Earth just like two satellites of Saturn which do the same thing. Lets say Venus is slightly inside of Earth's orbit, so it orbits the Sun a little faster, and over a 100 year cycle it gradually overtakes the Earth it its orbit. When Venus gets close enough Earth's gravity accelerates it while Venus's gravity slows the Earth-Moon system down, Earth-Moon then takes the inner orbit and Venus is in the outer orbit, and it takes another 100 years for Earth-Moon to overtake Venus ad exchange orbits with it so that once again the Earth-Moon is on the outside and Venus is on the inside.

So what do you think, could this be a stable situation, since it works for two of Saturn's moons?

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#214 2014-05-25 10:01:42

Terraformer
Member
From: The Fortunate Isles
Registered: 2007-08-27
Posts: 3,907
Website

Re: Venus

Gravitationally, possibly. Climatically? No.


Use what is abundant and build to last

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#215 2014-05-25 16:11:24

Tom Kalbfus
Banned
Registered: 2006-08-16
Posts: 4,401

Re: Venus

Terraformer wrote:

Gravitationally, possibly. Climatically? No.

Depends on how close Venus has to get to interact with Earth gravitationally to switch places with it.
1) there may be problems with Venus flinging the Moon out of its orbit. The Moon is about 384,399 km km away from the Earth, so ideally Venus would get no closer than 3 times that distance just so the Moon remains gravitationally bound to the Earth. that would place Venus at a minimal distance of 1,153,197 km from the Earth. At this distance the disk of Venus would appear slightly larger than that of the Moon, about 1.3 times the Moon's apparent diameter in Earth's sky. There would be a super-tide every 100 years on both planets. After a pass, an Earth year would get shorter and a Venusian year would get longer, and then after another 100 years the planets would switch places once again.

I got a distance of 149,615,000 km for Earth to get an orbital period of one year.
For Venus we want to start out with a year that is 0.99 of an Earth year.
The Venusian year would be 361.5876 Earth days long, and while we're at it we could give Venus a 24 hour retrograde spin, since that would be trivial compared to moving the planet out to almost 1 AU from the Sun.

The problem is I calculate an orbit with a period of 0.99 years would bring Venus to about 999,100 km from Earth. So lets make the Venusian year 360 days long.
That's more like it, to give Venus an orbital period of 360 days, it has to have an orbital radius of 148,176,300 km, which is 1,438,700 km from Earth at its smallest distance, which is further than the 1,153,197 minimal distance from Earth, in fact its 3.742725657 times the Moon's distance from the Earth. Venus would catch up with Earth in 73 years. Now the question is would this be close enough for the planets to exchange places. Maybe if someone had some orbital simulation software, we could find out what would happen. Another thing is the orbit of Earth would have to be made more circular, but if we're moving Venus around, this should pose no problem.

Last edited by Tom Kalbfus (2014-05-25 16:38:27)

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#216 2014-05-25 19:39:58

Tom Kalbfus
Banned
Registered: 2006-08-16
Posts: 4,401

Re: Venus

There are a bunch of interesting articles about Venus by the Moon Society.
Take a look here!
http://www.moonsociety.org/publications … bpaper.htm

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#217 2014-07-09 12:39:43

knightdepaix
Member
Registered: 2014-07-07
Posts: 239

Re: Venus

Just a small input from myself.

CO2 can be compressed into dry ice and then transform into some kind of polymer for storage. Sulfur itself can exist as orthosulfur allotrope but much energy is needed to reduce sulfur acid to sulfur. However if such reduction is given a go, the water and oxygen generated can be recycled for use, say in the space industrial station where all these reaction take place. Both CO2 polymer and sulfur can then be exported to another planet, say Mars where human or plant immigration happens concurrently.

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#218 2014-08-08 14:55:56

karov
Member
From: Bulgaria
Registered: 2004-06-03
Posts: 953

Re: Venus

http://phys.org/news/2014-08-rotation-p … y.html#jCp

a serious argument for not to re-spin Venus.

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#219 2014-09-24 19:43:41

Tom Kalbfus
Banned
Registered: 2006-08-16
Posts: 4,401

Re: Venus

Here's an interesting site about terraforming Venus, any comments?
http://www.worlddreambank.org/V/VENUS.HTM
VENUS UNVEILED
A terraformed Venus, one thousand years from now--
by Chris Wayan, 2003-4
VENUS.JPG
new? prepare for shocks - map - peoples and creatures - gazetteer - glossary - more worlds? Planetocopia!
Welcome to Venus! Venus as it will be, of course--the warm, living world we always imagined under the clouds, not today's inferno hiding under that mocking white veil. I've dated my portrait 1000 years from now, though Venus may not take that long to terraform. But it sure won't be as quick as Mars! There's shading, and cooling, and cleaning up the atmosphere, not to mention possible orbital tweaking... and the spin problem, and hailstorming (throwing a million Jovian icecubes at anything takes time!) Terraforming is like bonsai--patience, patience...
I've largely ignored human artifacts--towns, roads, dams, farms, factories, space elevators. Most science fiction uses other worlds as mere backdrops, but I want to take us out of the foreground and look at the land itself--Cytherian geography, climatology, ecology. This approach runs in my family. My mom paints landscapes, but she often quietly deletes all the works of humanity, to see what's underneath our buildings, wires and roads. Like her, I'm just a landscape painter... on a planetary scale. Except that living Venus will BE a human artifact--a work of art.

VENEIS.HTM#east
CONTENTS • Tour Venus! Regional maps and tours
• Portrait of Venus
• Climate zones
• What Venus needs ◦ Cooling
◦ The atmosphere
◦ What to do with excess CO2?
◦ Night and day
◦ Spin and seasons

• Suggestions? Email me!

TOUR VENUS

The heart of this site! Guided regional tours with maps, of...
•Ishtar's famous peaks, and its fertile, overlooked east
•East Aphrodite: Ulfrun's rainforest; Mt Maat, Atla, and huge Lake Fossey; the Jokwa Desert; Rusalka Bay; Dali Chasma
•Central Aphrodite: Diana Chasma, the ranges and deserts of Thetis, the great lakes of Artemis, and lush Cape Juno
•West Aphrodite: the alps of Ovda, green Cape Unelanuhi, and the tessera of Manatum and Hestia
•Eistla, Bell, and Tellus: out-Amazoning the Amazon
•Alpha and Lada, twin Earthseas
•Beta and Asteria's prairies and mountains, plus Hecate Chasma
•Phoebe's gulfs and tessera
•Themis's jungles, and the maze of Parga Chasma
•Dione and the Navka Archipelago, havens for strange creatures
•The South Sea islands, scattered and green: Imdr, Ishkus, Chuginadak, Puluga, Tonatzin...
SEE ALSO:
The GAZETTEER indexes and describes all the geographic features on terraformed Venus.
The glossary describes Cytherean terms like, well, "Cytherean."
The PEOPLES OF VENUS lists dozens of sentient species, their habits and habitats.

PORTRAIT OF VENUS

Later in this article I'll describe terraforming problems (Venus's heat, dryness, toxic atmosphere, spin), but frankly, all such talk is premature. We're still technological savages--we know what needs doing, but not how to do it! So why try? Let's treat the early, industrial phases of terraforming as a black box, and just assume we'll clean up Venus--somehow. My real interest is what comes next: Venus as a biosphere--as a place, a very big, beautiful place. This is a theme of this website in general; Dubia, the Earth with doubled C02, ignores the time of catastrophe to focus on what Earth'd be like once it settles down as a global hothouse. Same focus here: what Venus looks like as a world--not as an engineering problem!

As I've studied the radar scans and sculpted Venus's landforms, it's struck me how Earthlike they are--more than I anticipated from the comments of researchers, who I think are reacting to the current climate, not the landforms. Not just Venus's climate--the cultural climate here on Earth. Mars-mania is rampant, largely spurred by a historical accident: for centuries, when crude scopes and visible light were all we had, Mars made for fascinating viewing and Venus was a blank. But Venus is more Earthlike than Mars! It's closer in distance, size, mass, gravity, atmospheric density, tectonic activity. Yes, it's hot, and there are alien structures, and the absence of water-erosion has led to a pitted surface that'll abound in lakes and be short on river drainages, at least at first... but overall, Venus is beautiful--a complex geography that'll generate (in any terraforming model) fascinating continents with complex shorelines, islands, mountains, rifts, and lakes. In comparison, poor Mars is chunky, battered, lunar and brutal, with regions that'll never be viable under any terraforming scenario. But if any of Venus becomes livable, most of it will be. You'll never be far from water on Venus--or life.
VENUS2.JPG
Venus is an introverted girl. Unlike Mars or Earth, her surface is mostly shaped by inner forces, not weather or external impacts. The land looks stringy--ridges and arcs form tension lines connecting volcanic high points. It's as if a second veil lies over the real Venus--not of cloud, but of stone. What's going on inside isn't clear, but it's forceful, and not quite Earth's plate tectonics--nor Mars's cracking, static hot spots, and floods. The dominant theory at the moment postulates eons of deadlock and rising magma pressures, until, every half-billion years or so, catastrophic lava floods burst out, like Earth's Deccan or the Siberian Traps episode--but on Venus, these lava floods are worldwide, as if the planet reverts to its fiery birth. If true, such episodes may be triggered internally, or by large asteroid strikes.

But that doesn't explain the skein of arcs and ridges. My insticts tell me something rubbery is happening on Venus. I see elasticity everywhere--stretching, warping, squeezing till it corrugates. I'm a sculptor, used to flexible clays and acrylics, not a geologist--raised on plate tectonics, they tend to hunt for Terran-style plates or to reject plate tectonics utterly, some going so far as to deny large-scale crustal movements at all--just local spreading along rifts, and bubbling-up via coronas and volcanoes. I see wider movements! But not in plates--more like skin. Rubber tectonics... string cheese tectonics. (Io's not the only pizza!) The stuff's not just bubbling up under pressure. Sure, on the local scale (coronas, shield volcanoes, farras), vulcanism dominates, but some kind of large-scale stretching, bending or sliding is going on too. I just don't know what--or why.
VENUS1.JPG
Venus does have small Earthlike continents. But most of the surface lacks the sharp two-level nature of Earth or Mars, with their obvious seabasins and continents. Most of the landmasses I project are more like sea-floor rises and shallows, with no continental scarps. Now, Venus may have had an early oceanic phase, but the ancient shorelines are long gone, so I'm not restoring primal seas (as on Mars), just filling in modern lava-basins that may be not much older than Earth's present oceans.
Without fossil shores to guide us, sea levels are arbitrary. Mine are a few hundred meters higher than some terraforming proposals I've seen, but rather than try and re-create Earth with its sprawling continental interiors, I wanted to reveal as much of Venus's native topographic complexity as possible. The resulting coast is positively fractal--nearly every place on Venus is near water, and that's good for life.

My maritime Venus has a bit less dry land than Earth, but much more biologically usable land--fewer deserts or harsh continental interiors. And the seas will have wide, warm shallows--coral reefs? This Venus could sustain quite a lush biosphere--and it's a true sphere, unlike Mars's patchwork, pierced by stratospheric volcanoes and frayed by cold high deserts. Unlike Earth's, too! Pierced by polar caps, by Tibet, by the Old World desert belt, Earth's bio-"sphere" is more Martian these days than we think. It's been fifty million years since we had an unbroken biosphere. Swathed in thick air, Venus can be paradise--with enough water.

Besides, the impact of all those extra Jovian or Saturnian ice mountains will impart extra spin to Venus, which needs it. Even a modest rise in sea level allows a lot more ice-bombardment, since the surface area of the new sea increases as it rises. I think it's worth it. Still, if you like, you can build a Venus with a sea level half a kilometer lower (the basins are shallow, so that's about as low as you can go without getting mere chains of salt lakes, like Central Asia--desert country, please notice!) At this lower setting, you gain millions of square kilometers of land, at the risk of a harsher, drier climate. I've gone for quality, not quantity. Why settle for a hot Mars--or just another Earth?

CLIMATE ZONES


While I discuss the many terraforming options in detail below, it's likely Venus will have either a parasol or a swarm of shade-rings that cool the equatorial zone to something like our own subtropical temperatures. Why the equator? Just as the sun heats best at high noon, you get the most for your construction dollar by shading the high-noon part of the planet first. You can build a bigger parasol and shade the whole world if you want, but I've assumed a partial shade will do the job. So... a mild equatorial zone. Thirty or forty degrees north and south will actually be hotter, for the less shielded sun heats the surface to Earth-equatorial temperatures or more. The poles are cooler, drier zones, though not nearly as cold as Earth's. These warm and cool zones create two convection belts (Hadley cells) in each hemisphere, instead of the three on Earth (and terraformed Mars). Slowly spinning worlds tend to have larger cells anyway (Venus now has essentially one or no cells, while fast-spinning Jupiter has many tight belts) so I doubt that even a Venus with an Earthlike thermal gradient would have a three-cell system.
VENHADLY.GIF
Zones of falling air, especially where the prevailing winds come from inland, can cause deserts on Earth, usually around 30 degrees north or south. In contrast, Venus, with its tropical Hadley cells reversed, will have its few deserts near the equator (mostly in Aphrodite). There will be twin torrid zones near latitude 40 or 45 degrees. Ishtar and Lada, nearer the poles, will be drier and cooler, though only the highlands will be truly cold. Lakshmi Plateau on Ishtar could glaciate--and even if it doesn't, the Himalayan-scale ranges around it will. Personally I'd like to avoid large icefields, though--they generate harsh weather, and unless we induce Venus to spin with enough tilt to provide seasons, snow country will STAY snow country, i.e. dead. Mars will have enough of that already! So let's keep the climate mild enough so Lakshmi ends up as an altiplano, cool, windy, but grassy, fed by snowmelt from the Maxwell, Freyja and Akna Ranges.
Venus has next to no axial tilt now, unlike Earth and Mars. If we can set Venus spinning at all, I suppose we could impart any tilted spin we want; but for the sake of this experiment let's honor Venus's axis, and see what happens. No tilt doesn't mean no seasons--on Venus, my best guess is that night and day, each about a week long, will be the primary seasons--evening will be fall-like, late night rainy and wintery, morning springlike, afternoon summery. The week-long nights, under most terraforming scenarios, will be many times brighter than full-moon nights on Earth--more like daylight around Jupiter or Saturn. (See NIGHT AND DAY below.)

Summary: my climate model has a mild equatorial zone under the shade of mirror-rings, torrid zones in the mid-latitudes where the shade-rings thin out, and dry, cool but not icy poles. The air is dense, and will transport a lot of vapor, but surface winds are weaker than Earth's, since rotation is slow and thermal gradients between zones are milder. Spin is retrograde, so currents, prevailing winds and Coriolis effects all run backward. Deserts will cluster on equatorial east coasts where dry air descends, while mid-latitude west coasts will be the rainiest places on Venus. (It all gives me an odd sense of deja vu, as I spin my Earth globe, looking at Oregon and England. Plus ca change, plus c'est la meme...)

Oh, well! Let's change subjects, now... AND tone. For the megalomaniac portion of our show, we now switch you to that engineer's delight, "Terraforming Fantasies." Hang on to your skepticism--you'll need it.

WHAT VENUS NEEDS

Terraforming Mars involves only one truly big project: adding a decent atmosphere. This isn't simple--free oxygen's needed, and Mars is nitrogen-poor, and you need enough greenhouse gases to warm the planet yet not poison animal life--like us. But except for nitrogen, the ingredients are there on Mars already. Even extra water may not be needed--certainly much of it is there already. The Martian orbit, axial tilt, rotation, geography, and level of tectonic activity are all acceptable right now.

But Venus has multiple problems which must be solved simultaneously -- at least by the standards of geologic time.
1.Cooling the planet. Clearly linked to this is:
2.Disposing of excess carbon dioxide. I don't say "carbon sequestration", since sequestering the carbon's not the only option, and the extra oxygen's a problem too.
3.Light and dark. I almost called this night and day, or the spin problem, but some solutions leave Venus with no clear or regular diurnal cycle, and some solutions don't even require Venus to spin.
4.Adding water. This is perhaps the simplest problem, but hailstorming Venus on the scale required would take time and does have risks.

COOLING

I've been debating half a dozen ways to cool off Venus. Solutions inevitably affect the other three problems!
1.Shade Venus with a very large parasol at the Lagrange point between Venus and the sun. Due to the large apparent size of the sun from Venus, and the distance of the Lagrange point, such a sunshade would have to be considerably wider than the planet! Expensive, and it doesn't help light the nightside, which other types of sunshades would.
2.Shade Venus with a large orbiting parasol. Several structures are possible, such as a strip half an orbit long, or an orbiting ring with alternating shades of night and openings for day, or multiple parasols in a ring. The total area of such sunshades is again very large. These are big engineering projects, and the planet's life depends on them. Kind of disturbing, isn't it? Still, orbiting parasols have the advantage that when a parasol is on the nightside it can function as a nightlight. If Venus's rotation remains slow, as it probably will, lighting the long night is a major issue.
3.Shade Venus with swarms of quite small orbiting mirrors (structures only 1-200 km across, or even less, instead of 10,000-100,000 km as in the first two proposals) which again function as multiple nightlights on the dark side. This is the first option that requires technology not much advanced beyond our own. A single ring of these would only shade Venus's equator, of course, so this scenario requires multiple tilted rings to cover all the lower latitudes at all points in Venus's year. It's the center of Venus's disk, facing the sun, that really needs a shield; the poles and dawn and dusk get no more insolation than Earth's tropics.
4.Shade Venus with even smaller, lower-tech devices: rocks, basically. Venus is too warm for ice-rings, of course, but any light-colored pebbles will do--plastic snowflakes? How about those clever little octahedral beacons that reflect light back to its source no matter how they're oriented? Well, whatever they're made of, each concentric ring must have a different orbital tilt, so that most of the surface gets some shade most of the year. I admit it sounds too complex to be stable, but why not? Unlike natural moons, these objects need not be heavy enough to perturb each other much. Light-pressure may be the main problem.
VENRINGS.JPG
5.Don't bother to shade Venus! At least not much. Venus's present atmosphere (hot though it looks to my carbon-based readers) has a couple of admirable features: it reflects quite a lot of insolation, and it distributes its heat very evenly, from light to dark side, and equator to pole--at least solar energy isn't concentrated on the day-side equator. The only problem is the sheer amount of heat trapped. Yes, Venus gets more sun than Earth. But even high noon on Mercury is only about 670 K, and Venus gets less than a third as much solar energy--and if you spread it over the whole planet, not just the dayside tropics, it's less than a sixth. If we retain lots of thick white clouds (NOT of sulfuric acid, of course) to reflect a lot of light, and lower carbon dioxide levels enough, we might create warm but acceptable temperatures (around 300 K) all over the planet. If such an atmosphere alone wasn't enough, add some equatorial rings of mirrors (a simpler version of option 3). Since the dense atmosphere distributes heat so evenly, only the total insolation needs to be controlled, instead of a perfect, pole to pole shield. This is, I think, the simplest solution, if it's thermodynamically feasible, and if you don't mind a white, featureless sky, or at least a very cloudy one, most of the time.
6.Move Venus outward, using its excess atmosphere as reaction mass! This supposes cheap fusion power, huge, high-speed jets, and a lot of time, but then any proposal to terraform Venus requires larger structures and higher technology then Mars does. Where to put Venus? Either...◦Midway between Mars and Earth, about 20 million miles from each. That's nearly as distant as it is from Earth now--far enough to avoid perturbation problems. At this distance, insolation should be about right for a low-CO2 atmosphere several times Earth's density. No parasols, no mirrors... ideal.
◦Or pair Venus with Mars, much like Earth and Luna, but at a distance of 500,000 to a million miles. The tidal stress created by Mars in Venus helps replace the reduced tidal stress from the now more distant sun. Venus, being much larger, would induce in Mars tidal stresses comparable to Earth's, helping Mars to wake up geologically and belch CO2, thawing it out... Two for the price of one!
Moving Venus is a techno-geek's approach, and I feel a distinct reluctance to even explore such macho fantasies. But it might pay off: two viable worlds without elaborate shades or orbital mirrors. High initial risks (see NIGHT AND DAY #2, below, for some of them), but a safer, stabler result. Besides, think of those moonlit Martian and Cytheran nights, with a living, full-color world shining down... romantic, yes?

THE ATMOSPHERE

Venus's atmosphere gets a bad rap. One little flaw, and that's all you hear about! But if we can remove the CO2 from Venus's current atmosphere, what's left is not bad at all--three to four atmospheres of mostly inert gases. This thick residue has advantages over Mars or Earth's atmospheres:
•it distributes heat evenly. This is good, since we don't want scenic Ishtar to go all glacial on us. An even warmth is fine--just a bit less than now, please!
•a thick atmosphere held in by a deep gravity well is stabler. Getting the mix we want takes work, but if we do achieve it, we won't have the problems with air loss that leaky, low-grav Mars is prone to.
•Air pressure of three or four atmospheres, combined with slightly lighter gravity, makes wings much more efficient. Expect Cytheran life to be winged--even large creatures, like humans. Whether bioengineered or strap-on, angel wings may be the normal way to get around. Given the planet's geography--no matter how you set the sea level, it's going to be archipelagoes and shallow seas and continents full of lakes--flying and sailing, not roads, make the most sense. Dirigibles make sense soo--since their payload would be at least triple that on Earth, they'd be smaller and safer. Planes require less wing, too. Like low-gravity Mars, Venus will be a world of wings.
•thick air holds more water vapor. Winds on Venus are weak now, near ground level. We may need to force Venus to spin faster not just because we want a diurnal cycle, but to stimulate surface-level winds--storms have to get inland where rain's needed. But at least the air has the potential to transport enough moisture! In Mars's highlands, for example, the air's so thin that even saturated air just won't yield much precipitation.
•a thick atmosphere is an excellent UV shield, and with the sun this close, we need it. It's also a better shield against small and midsize meteors, though of course nothing can stop big impacts but high-tech intervention.
WHAT TO DO ABOUT EXCESS CO2?  1.Filter out inert gases (we want to keep them) but jet most of that carbon dioxide into the sun. This is a big engineering project, and risky (see NIGHT AND DAY #2 for details). But with fusion energy and the ability to build big enough, focused enough jets, it's not impossible, and might not even take too long.
2.Clathrates on the bottom of the new seas have been proposed, but how do you cool the planet enough to create seas while the CO2's present? Centuries of darkness, via a big parasol, till Venus freezes? Pelting it with Jovian icebergs will heat it up again, and every collision endangers the parasol. So we'd have to pelt it first, till the atmosphere's loaded with stratospheric water vapor (another greenhouse gas, unfortunately), THEN shade and cool it, and wait (years? decades? centuries?) for rain... precipitate the stuff... and pray it never breaks free! Would you want to live atop a CO2 bomb like that?
3.Diamonds! Built via nanotechnology, or large fusion-powered plants? This model has molecular assemblers constructing a sea-bottom stratum (1-200 meters thick) of diamonds or carbonates, comparable to our layers of limestone. Or toss the diamonds into space at an angle, adding more spin. If you can't bind all the oxygen into rocks (and I'll bet you can't--this isn't a wispy Martian or Terran atmosphere we're dealing with), jet the excess into space--it's not the hazard to other planets that migrant CO and CO2 would be (see NIGHT AND DAY #2, below, for risk analysis). It's true that any diamond scenario requires advanced factories working on a hellish surface, instead of nice comfy space work, but it has virtues, too--unlike the other models, the speed mostly depends on the scale and efficiency of a purely industrial effort. If a model was found that really worked, with vast numbers of self-replicating factories (at any scale, nano- to mega-) Venus could be cooled much faster than by sunshading alone. Indeed, without carbon dioxide holding in the heat, full shading might not even be needed. Hot oceans in a few generations? Sounds absurd, given at the scale of the project--but then, no one thought Earth's climate had catastrophic phase-changes, either. Wrong!
NIGHT AND DAY
I've been mulling over ways to create a diurnal cycle on Venus.
1.Hailstorm Venus--that is, pelt it with outer-system icebergs in cometary orbits at high speeds, and have these collide with the planet at low angles, imparting momentum. Part of the reason my Venus has sea levels set rather higher than some terraforming models is that I want as many icebergs as I can get, to impart as much spin as possible. I estimate that a third of a billion cubic kilometers of ice (about 1/15,000 of Venus's mass, and about the same mass as the atmosphere we want to vent or sequester), sent in as icebergs in fast enough orbits, would give us an acceptable sea level AND get Venus spinning about once every one to two weeks--not fast, but better than having nights that last months.
The problem with high-speed ice-bullets is that you mustn't miss and hit Earth--not once out of hundreds of thousands of strikes. A single hit, even at low speeds, would be catastrophic. At high speed (say 60-70 km/sec), the size of an ice mountain is effectively multiplied by ten, putting the energy of such a collision in the continental-firestorm category. Not something to play around with! And of course, to reach Venus (unlike Mars) the hailstorm must cross Earth's orbit. This is one reason the whole project won't begin for a long time to come. Ice ferrying must be absolutely routine--a mature technology with redundant safety layers. And you need an equally mature sociopolitical structure--no wars, no terrorists, no cost-cutting capitalists skimping on safety margins... In short, you need utopia--at least compared to our current barbarism.
2.One tempting if brutal method is simply to eject much of the atmosphere at very high speeds from an angled jet, forcing the planet to spin AND getting rid of unwanted CO2. Mt Maat, as high as Everest and exactly on the equator, is the logical spot for a fusion-powered jet, though it may be a wee bit, um, active. Still, siting giant fusion jets atop live volcanoes shouldn't faze anyone who's gear-headed enough to turn Venus into a rocket-powered pinwheel for a century or two. No, that's not the real problem. Where's all that high-speed CO2 go? To give us enough reaction to spin Venus, it has to go fast, so even if you fire it sunward, much of it will spiral out to Earth's orbit and beyond, filling the plane of the inner Solar System with a thin cloud of carbon, oxygen, carbon monoxide and CO2. We're ejecting nearly 100 times Earth's entire atmospheric mass--that's about THREE HUNDRED THOUSAND TIMES the CO2 content of our atmosphere. So, if even a millionth of the soot spewing from Venus's smokestack drifts into Earth's gravity well, our CO2 levels would rise dangerously--and that's on top of industrial warming. Why terraform Venus by veneraforming Terra?
This also limits proposal 6 above, in which Venus gets moved outward using its atmosphere as reaction mass. The most efficient way to do this is to jet off the atmosphere behind the planet, in its orbit. But this again would leave a large plume of CO2 spiraling out toward Earth. In both cases, the only safe jet would be a single one pointing at the Sun--less efficient and not imparting any spin. Even this assumes dumping carbon on the sun's surface doesn't affect its light output, magnetic lines, sunspot patterns, or flaring. Yeah, let's shoot a giant fire-extinguisher at the sun and see what happens! Don't you just love engineers?
Still, the angled-jet scenario is so tempting because it gives us twice the spin that simple hailstorming does--you might even get Venus turning once every three days--so fast that a high-noon parasol and a midnight mirror could make a 24-hour light-and-dark cycle, simplifying things for any number of Earth species. There's an emotional factor, too: "let's make that damn CO2 do something useful for a change!" But that doesn't justify the risks, does it?
3.Let Venus's spin stay about the same--that is, very slow--but build a parasol out at the La Grange point, louvered like a Venetian blind, opening and shutting to create day and night. This seems complex and prone to wear and tear. Simpler: let the shield be a rotating shape that allows a lot of sun when it's edge-on and very little when it's full-face to Venus, or build a spinning flower with petal-shades causing local night, and missing petals for local day.
But a La Grange shade won't light the long night. A mirror for the night side, placed in the other La Grange point, high above midnight, would have to be several times Venus's size--that point's a long way out. And the shadows of Venus and the sunside parasol would reduce its efficiency--a large ring would be more efficient than a disk. A better solution might be a smaller ring-shaped mirror, a mere 1.5 times Venus's diameter, floating closer to the nightside. Build it light enough and Venus's gravity could be offset by the intense light-pressure on the mirror. Again this would require constant supervision, but in theory at least, it could be made to float in permanent balance. Besides, it'd look pretty, wouldn't it? Of course, such a proposal is only viable after the death of capitalism... or the damn thing would be covered with ads. Come on, you know it would.
4.A large orbiting sunshade or sunshades, in a 24-hour orbit (around 40,000 km out) would be an even more massive project, and big orbiting mirrors, with low mass compared to the light pressure on their surfaces, might be prone to drift or orbital decay. Though, surely a civilization capable of building them could maintain their infrastructure... right? Our own build-it-and-forget-it society is not encouraging in this regard! Still, such 24-hour mirrors do have the advantage of doing three jobs efficiently without moving parts--cooling the dayside, lighting the night, and creating a Terran diurnal cycle regardless of Venus's spin. Plus, a great silver arch in the equatorial sky would be beautiful--rather Saturnian, if harder-edged. It's just a big investment. We're talking about an arc of mirror over 100,000 kilometers long!
5.The simpler orbital-mirror program described in COOLING 3, with multiple, tilted Saturnian rings, not at "24-hour" distances but only a few thousand miles out. Each disk-mirror, 1-200 km wide, would make an extremely bright "full moon" in the night sky, though of course they'd wink out around midnight as they pass through Venus's shadow. Sunlight around Venus is nearly twice as intense as on Earth, and of course the albedo of a mirror is far higher than a moon of the same diameter. A sky dotted with many such moons could, I estimate, reach 1-4% of daylight levels on earth--like full daylight on Jupiter or Saturn, and a thousand times the brightness of our full moon. It'd be a shifting, forever changing dawn/dusk light, perhaps a bit like our Arctic. Not bad for technology we could almost deploy today!
6.Light up the night on the ground. This sounds absurd, but I live in San Francisco, a city famous for its fogs. When there's a low-lying cloud layer, the city lights can cumulatively light the night sky much brighter than moonlight--and they're not even trying! With cheap fusion power and lights aimed upwards at the bottom of Venus's clouds, daylike illumination could be achieved. It requires a permanent cloud layer, AND it produces waste heat we don't want, but it's still worth noting. Brute force as a last resort! (But wouldn't Frank Herbert have added "...of the incompetent"?)
SPIN AND SEASONS
The most spin I can manage, so far, is a slow Cytheran day about two Earth weeks long, which would also be the equivalent of Earth's seasons, warm and cool, dry and wet. The fourteen-day climate cycle might run:
1.SUNDAY: when the sun rises, of course! Low, dramatic light all day; morning rains (if any) break up into scattered showers. Tricky winds as the warm front of day sweeps across the world.
2.MONDAY: early spring. Flowering in response to the night rains. Low golden light. Mild temperatures. Clouds and showers patchy at most.
3.TUESDAY: spring, warming, clouds clearing. Bright sun, though little brighter than Earth's; at lower latitudes the rings or moonlets tame the sun's brilliance artificially.
4.NOONDAY: clear, warm, bright, but with constant eclipses (or a smoothly dimmed sun, depending on optimal moonlet-size).
5.THURSDAY: the Cytheran summer, the hottest part of the week. Dry in most regions, though the two Amazonian belts may have thunderstorms.
6.FRIDAY: summery, but cooling toward fall by noon. Thunderstorms fade in the torrid zones.
7.SETTERDAY, when Irish setters fall from the sky. No, no, when the sun sets. Low, dramatic light. Many flight-accidents due to glare and shifting winds from the cool night-front chasing sunset around the world.
8.DUSK: the sun goes down, the sky flames--and the display lasts all day, changing hourly. Mild but variable temperatures.
9.EVE: a mixture of dim blue horizon-light and bright ringlight--total light rivals good indoor lighting on Earth, with colors brightly visible. Cooling.
10.RING: maximal ringlight, as bright as noon on Jupiter, intermittently blocked by increasing clouds, even some showers. Cool to cold (for Venus).
11.YULE: midnight, and theoretically the darkest night, since the shadow of Venus on its rings passes overhead; moonlets or rings turn reddish and dim as they enter the Shadow, picking up heavily filtered sunset light. Rain in many regions. Yule will not be 24 standard hours long, though all the other days are. Kim Stanley Robinson has suggested for Mars that we keep Earth hours, minutes and seconds, and accomodate the slightly longer day by a time-slip after midnight. On Mars it's only 37 minutes, but on Venus, depending on the spin that's finally achieved, the Cytheran Timeslip could be substantial. Yule might only be 12 hours long, or 40--or not exist at all.
12.RAIN: steady rain in many regions. Stormclouds make this the darkest night in wetter regions--only a few times brighter than a clear full-moon night on Earth, with colors dim, though still visible of course.
13.WITCH: the thirteenth day in the cycle--the witching hour. Rain in many regions, but the sky may start clearing late in the day. Predawn light begins to supplement bright ringlight, making the brightening even more noticeable. If clear, Witch is as bright as Ring or Eve--like daylight in the Jovian system.
14.DAWN: an all-day spectacle--turquoise light slowly drowns the white rings, and then green, gold, salmon, and fiery magenta fill the sky. Toward midnight, the first rays of direct sun.
It must be obvious by now that the "days" of such a calendar function more like hours on Earth or Mars--as local timezones sweeping round Venus. It's always Tuesday somewhere on Venus--all fourteen days are always happening simultaneously. On the other hand, ten o'clock happens all over Venus at once. When you cross timezone-lines, you adjust your calendar by one day--not your watch.
Longer intervals will likely be measured in these fourteen-day cycles (let's call them months) and 225-day years of sixteen months each--though, perhaps, since Venus's year doesn't affect its seasons much, people may measure long time intervals in Terran years for convenience. Or Martian or Jovian years--we shouldn't jump to conclusions about who'll terraform Venus, or be the cultural center of the Solar System a thousand years from now!

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#220 2014-10-20 19:09:13

SpaceNut
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From: New Hampshire
Registered: 2004-07-22
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#221 2014-10-21 03:49:56

Tom Kalbfus
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Registered: 2006-08-16
Posts: 4,401

Re: Venus

Heavy metal frost, like gold for instance? Probably more like lead.

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#222 2014-10-24 01:13:35

karov
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From: Bulgaria
Registered: 2004-06-03
Posts: 953

Re: Venus

fig3_PR_TAmari.jpg

here you are all the hydrogen one needs to terraform Venus.

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#223 2014-10-28 08:11:54

Void
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Registered: 2011-12-29
Posts: 7,830

Re: Venus

I wonder if Iron Pyrites.  Maybe too hot for it though.  One trick I might think to try to employ to get rid of the acid clouds, would be to inject iron dust.  Then that would condense.

Alternately, I am thinking automated floating machines, which extract Carbon from the atmosphere to make soot.  Nuclear winter notion.  The carbon would also react with the acid clouds changing the chemistry.

Smog?  SO2 clouds instead?

Anti-Greenhouse effect like Titan.

And then there would be the notion of just extracting CO, that would be like releasing a fuel into the acid clouds.  Of course you would be releasing a lot of O2, but that can likely dissolve into the atmosphere and stay out of the way long enough to make chemical changes.

Having a sooty atmosphere with possible S02 clouds, perhaps the Acid clouds would be driven down far enough to react with the rocks of high mountains and dissipate.

The robotic floaters, making the soot and CO, could be visited by humans occasionally when certain repairs are required, but I see no reason why you would want to put people at risk until the environment was greatly improved.

I am more interested in harvesting chemicals from the atmosphere, by intercepting them in the very highest layers, capturing them and so using them.  I see value in using Carbon in Orbit, to assist in that project.

And Karov I am interested in figuring out a way to capture and use the solar wind as well.

Last edited by Void (2014-10-28 08:13:06)


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#224 2014-10-28 09:06:31

RobertDyck
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From: Winnipeg, Canada
Registered: 2002-08-20
Posts: 7,936
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Re: Venus

Soot is not an answer. Carl Segan wrote the first formal paper on terraforming; written in 1961. His idea was to seed the clouds with algae. Those algae that floated too deep into the atmosphere would be incinerated, forming soot that would float down and releasing oxygen. But that was written when scientists thought Venus had a 6 bar atmosphere. It turned out to be 92 bars surface pressure. In his book "Pale Blue Dot", Carl Segan pointed out that if you convert all CO2 in Venus atmosphere to soot and O2, that soot would form a layer of graphite several kilometres thick, and oxygen would be 68 bar surface pressure. In that much oxygen, graphite will spontaneously combust. So the graphite would burn back to CO2. All your work is un-done.

Since the late 1970s, I've argued the idea of seeding clouds with a microorganism is still a good one, but algae is isn't it. We need to genetically engineer an organism that will sequester both carbon and oxygen as something that is stable, non-flamable, and non-toxic in soil. Once most of the pressure is gone, then release a geneticly engineered version of cyanobacteria that will thrive in clouds and release oxygen. And ensure the first organism is poisoned by oxygen, so the second organism stops the first one.

No massive industrial effort. Just genetic engineering, seed the clouds, and wait while life does its work.

Of course capturing hydrogen from solar wind is a great idea to add water.

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#225 2014-10-28 10:28:26

Void
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Registered: 2011-12-29
Posts: 7,830

Re: Venus

Actually, I'm not going to settle on that.

I mentioned 3 manufactured materials: Soot, CO, and Smog.

https://web.anl.gov/PCS/acsfuel/preprin … 9_0169.pdf

Causing the creation of Sulfur Dioxide from a reaction of Sulfuric Acid with Carbon (Soot),

Objective Sulfur Dioxide clouds, and smog layers above the Sulfuric Acid cloud layer.  Cooling, lowering the Sulfuric Acid cloud deck, reducing the amount of Sulfuric acid.  Hoping to get some of it to react with mountain rocks as thing cool.

Meanwhile, injecting Carbon, Carbon Monoxide into the very upper atmosphere where the shredding effects of radiation should render it Monatomic.  Harvesting the upper atmosphere by means not yet very well mentioned, but I have notions, which comes before a plan.

The point being I want the atmosphere of Venus.  Want to be able to capture it to orbit, want Carbon especially, since there are so many things that can be made with it.  Carbon would be quite useful to attempt to capture from the atmosphere I think, and Hydrogen from the solar wind.

Terraforming Venus is an afterthought.  Indeed, if can extract Carbon, Oxygen, Nitrogen to orbit, then very rich, maybe can sell it, make things out of it.  If you can capture solar wind as Karov has tilted towards, then you might also have Hydrogen.

But Sulfuric acid is the enemy of machines which would float and alter atmospheric chemistry.  So, get rid of it as fast as you can.  I would also like to be able to get Sulfur to orbit, but that's an optional desire.

As for habitation, if you can extract the atmosphere then why squander it.  After the chemistry has been made more friendly......then floating cities with people.

Last edited by Void (2014-10-28 10:52:52)


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