Floating Venusian cities or Venus vs Mars vs Titan revisited

nickname · 2007-05-14 05:44:33

noosfractal,

Thanks for the input on the 1 bar Venus to Mars.
Was more of a guess than anything for me.
Not much literature to surf on such an concept.

Ammonia asteroids better source, but are they easier to get?
Venus is close and has lots of freebies.
A good candidate asteroid would be far away and fuel expensive.

Then again pretty much any gaseous asteroid and a bunch of super greenhouse gas will change Mars.
Maybe just water/ice asteroids would suffice, or even a decent comet crash.

Spatula · 2007-05-21 12:06:05

Spatula,
If we take into account all the solar, C02 atmosphere and possible heat generated atmospheric conditions, Venus is still much hotter than the temperature can account for.
My guess is that Venus produces a lot of heat from the core directly to the surface.

The atmosphere retains the planet's geological heat as well as the Sun's input. I don't know the extent to which it does this. All I know is that atmospheric physics predicts a planet with Earth's atmosphere in Venus's position as having an average surface temperature of 25-36 degrees Celsius, compared to Earth's 13-22. Not as comfortable, but good enough. Removing the atmosphere until it's comparable to Earth in its mixture and density is all that needs to be done.

It's no more geologically active than Earth. Worldwide Volcanism would actually help cool the planet down in the absence of a strong greenhouse effect. It increases the planet's reflectiveness. Nice thing to have.

nickname · 2007-05-21 17:49:28

Spatula,

It's an interesting oddity on Venus.
One that hasn't been looked at much, or simply not much data to take an educated guess at.

The extra temperature is still difficult to explain away, but your idea seems pretty good for most of the extra heat if it is produced in the correct wavelength for c02 reflection.

It's a pretty bleak thought to think that even if we made Venus earth like that the surface might take a very long time to stop producing its heat pulse.
Throws a pretty big monkey wrench into teraforming ideas for the furnace world.

Hmm the earthlike conditions on Venus...
I seem to remember wrestling with karov for quite a while about the 100c problem on the equator on Venus even with earth like atmosphere.

Those extra 10 or 15c are a killer to keep Venus from overheating h20 at 1 earth bar.
The suns input at Venus and additional heat pushed the equator dangerously close to 100c max and a few rare days above it.

Only 1 or 2 earth length days of h20 steam starts a global heat cycle runaway.
If i remember correct we decided on about 1/2 bar of earthlike atmosphere to avoid it, but that didn't take into account the extra unknown Venus heat source.
Probably still pretty safe at 1/2 bar though.
45 sun block wont cut it on Venus, no tanning allowed.

Spatula · 2007-05-22 00:43:31

Those extra 10-15 C are air temperatures only. The actual ground/water temperatures are 15-25 degrees colder at least, and are certainly not going to come close to boiling.

There are many complicated things like that that enter into it. Planets with an axial tilt will be hotter on average than planets without one. Having longer days/nights will affect the temperatures too. Atmosphere thickness decreases the variability of the temperature. Venus, with a thick atmosphere, has the same temperature over the whole surface. Mercury, with no atmosphere, is hot enough to melt lead during the day, on the equator, and cold enough to freeze nitrogen on the opposite side.

The more I look at Venus, the more I think a thicker atmosphere would be good for it. It would raise the average temperatures, but it would lower the distribution of temperatures much more, so you wouldn't see the months of 50 C torture on the equator that you'd see with an Earth atmosphere. It would also lower the perceived temperatures, due to increasing the speed the air conducts heat to any organisms walking around.

(For instance, if you go outside in 15 degree weather, it's very comfortable, pleasant. If you go swimming in 15 degree water, it's incredibly freezing cold. The increasing density of the medium increases its specific heat. An atmosphere twice as thick will have a much higher specific heat, so temperature deviations from the human body's 36 C will seem correspondingly hotter/colder). Heck, it would also increase the boiling point of water and block solar radiation. Less skin cancer is a good thing.

In fact, I think I just sold myself with this post.

nickname · 2007-05-22 05:06:24

Spatula,

A 2 bar Venus has its advantages, mainly the two you mentioned.
Heat distribution and boil point of water.
And radiation protection as well of course.

A 2 bar Venus will boil water at around 104c, so its a further 4c margin to a runaway steam problem.

A 2 bar Venus also has a down side of more than 4c heat retention over a 1 bar Venus, so the gain is actually a loss if we are trying to set the boil point margin higher.

On earth we only get the rare days above 50c and on rare places at 1 bar.
But if we deduce those number to Venus we get a similar number of 100c days on Venus in rare places since the sunlight is twice as strong.

Another problem on Venus is that land and water has a much longer to heat on Venus with its slow rotation compared to earth.
We could expect places on Venus to exceed 120c for long periods of time.

Venus with 1 bar though won't see much sunlight make it to the ground because a 1 bar Venus would be completely covered in clouds and raining about 95% of the time.

Just the evaporation rate from higher sunlight and higher atmospheric temperatures will produce clouds about 4 times as many as on a 1 bar earth.

I believe a 1 bar earthlike Venus would be a rain world as log as its stays under 100c.
This planetary cloud mechanism might be a very good thing for Venus to keep temperatures steady and below 100c everywhere.
That much h20 in the atmosphere is also a pretty good radiation protection, so its a win all around for a cloudy wet Venus.

No need for sun block, bring umbrella

Spatula · 2007-05-22 10:42:10

I don't see how you're going to get 100c anywhere on the surface unless you have zero atmosphere. The average temperature of the planet wouldn't support that. You're going to have to explain this one.

nickname · 2007-05-22 17:12:58

Spatula,

1 Earth bar and 2x sunlight = 2x Earth temperature conditions.
Actually Venus will be a couple degrees warmer than 2x Earth due to additional radiation in the atmosphere, and many degrees warmer in local areas on Venus, due to a very slow spin rate allowing local overheating.

The warmest days ever on Earth gets to over 1/2 the boil point of water on a fast spinning globe able to shed heat well.

The warmest days on Venus will boil water at 1 bar.

At 1/2 bar the boil point is less than 100c at 98c but the max equator temperature would be about 60c-75c
at 1 bar max equator 104c. boil point of water 100c.
at 2 bars max equator 114c. boil point of water 104c.

If we have even a few hours with boiling water anywhere on Venus the runaway steam cycle starts.
Steam is an very efficient greenhouse gas.
This is probably how Venus became the way it is.

John Creighton · 2007-05-23 00:46:45

A 2 bar Venus will boil water at around 104c, so its a further 4c margin to a runaway steam problem.

How is there going to be a run away steam problem if there are no oceans.

nickname · 2007-05-23 04:50:16

John Creighton,

Earthlike conditions

Without lots of water i believe Venus would produce lots of N02 out of an earthlike atmosphere.
Very funny place

Venus is pretty dry less than 1% available water in the atmosphere, but .5% of 92 bars is still quite a bit of water available.
I'm guessing we wont throw that away when we teraform.
No oceans for sure but certainly puddles and ponds.

And who would leave Venus with 1 bar of earthlike atmosphere and no water more than a few ponds anyway?

Spatula · 2007-05-23 16:48:15

Spatula,
1 Earth bar and 2x sunlight = 2x Earth temperature conditions.
Actually Venus will be a couple degrees warmer than 2x Earth due to additional radiation in the atmosphere, and many degrees warmer in local areas on Venus, due to a very slow spin rate allowing local overheating.
The warmest days ever on Earth gets to over 1/2 the boil point of water on a fast spinning globe able to shed heat well.

This is all wrong. If you're going to say 'twice the temperature', you should be using absolute temperature. The temperature on Earth is 287 Kelvins. If the temperature on Venus were twice that it would be 574 Kelvins with an Earthly atmosphere, over 10,000 with its runaway greenhouse effect, which adds more than 400 degrees Celsius to its temperature. On Mercury it would be over 20,000 Kelvins.

It doesn't work like that. The amount of sunlight corresponds logarithmically to the amount of heat, for planets with the same atmosphere. The main reason for this is that as something gets hotter, its specific heat decreases, causing it to absorb light as kinetic energy less efficiently. Along with that, the atmospheric distribution of heat will be much lower, since the poles will heat faster than the equator, and the equator is an extremely large area where temperature increases will spread out. Even more in-depth than that, we're talking about heating the oceans along with the atmosphere, and oceans tend to be very good at canceling out increasing heat within a certain range. Instead of having a hotter ocean surface, the extra heat would propagate deeper into the water, resulting in thermal expansion.

Notice how global warming seems to be hitting the poles a lot harder than the equator? The only reason the equator's gotten slightly hotter is that the continents limit the efficiency of transferring heat to the poles through ocean currents.

I've been over the most likely method of terraforming Venus earlier in the thread, and it involves creating a global ocean with approximately 80% coverage. This ocean would contain only a quarter of the water Earth's has, but the distribution of elevations on the surface, and the effect of thermal expansion on the upper levels of the water will cause it to have a bit more coverage than Earth's own ocean. This is essential for keeping Venus comfortable at the equator, and it's practical. You need an ocean full of photosynthesizing diatomes if you want a functioning oxygen/carbon cycle.

nickname · 2007-05-23 18:27:30

Spatula,

Not my math for the results of a 1 bar Earth atmosphere on Venus.
I just gave you the results i was given.

Earth 9c average above what it would be with no atmosphere or average 13c with high temperatures 41c warmer in local locations.
Highest expected local temperature on Earth 54c.

Venus 9c x2 above what it would be with no atmosphere or average temperature of 33c, we can expect 82c warmer in local locations.
Highest expected local temperature on Venus 115c.

How long did it take life on earth to lock away maybe 5 to 10 bars of c02?
500 million years? 1 billion years? 2 billion years?

How long for Venus with 92 bars and no open water for life to exist in?

How do you propose to get water to form on a 92 bar co2 atmosphere with a 460c surface?
Above 114c at 92 bars water is just steam, a greenhouse gas much more efficient than c02.

3 bars already nitrogen so you will also have to reduce nitrogen content to 3/4 bar.

And don't expect to input 44 bars of hydrogen to do the trick of converting all that co2.
Aside from the many millions of years project to do such a thing, the heat from the h20 creation reaction itself would overheat Venus even if it was below 100c.

Don't expect to cool Venus with shade, the solar wind and solar storm effects are much stronger at Venus than earth, a man made shade project won't endure, it would also be astronomical in price.

Sorry to be so blunt, but these are the facts to work with when trying to teraform Venus.

Spatula · 2007-05-23 21:37:30

And don't expect to input 44 bars of hydrogen to do the trick of converting all that co2.
Aside from the many millions of years project to do such a thing, the heat from the h20 creation reaction itself would overheat Venus even if it was below 100c.

Hey, terraforming is expensive. It would require a massive space economy existing beforehand, and probably thousands of years of implementation. The process is very complicated, and many things have to happen at the right time. For a planet that would become useful for billions of years, it's worth the investment.

However, the process fixes a significant amount of mass in the atmosphere as solid carbon and organic compounds. That will reduce the pressure and temperature significantly. The water formed will also be able to do something that CO2 can't: form clouds in the higher atmosphere, where Venus is actually quite cool. These would act as a giant sunblock, letting more radiation out than in. They would gradually precipitate, and evaporate in lower parts of the atmosphere, moving heat through the cloud barrier. This happened in Earth's history before.
http://en.wikipedia.org/wiki/Water_vapor

Water isn't a greenhouse gas in quite the same way CO2 is. It converts certain types of radiation into heat efficiently. When you microwave something, you're moving the water molecules primarily to heat it up. However, unlike CO2, which is always a gas in Earthly climates, water undergoes phase changes, during which it absorbs heat at different levels of efficiency. As a liquid, it's extremely efficient at absorbing heat, while as a gas it's much less efficient. Because of this, it tends to evaporate and move heat higher into the atmosphere, radiating a lot of it into space.

The confusing part is that because we have standing oceans, our surface albedo is a bit lower, and earth's oceans absorb more heat and spread it around the surface and into the atmosphere, making the planet a few degrees warmer.

It's a temperature moderator. It's good at lowering temperatures too high, and raising temperatures too low. Very useful for carbon chemistry.

nickname · 2007-05-24 05:53:30

Spatula,

Venus the catch 22 of chemistry.

The only way i could get around all the persistent catch 22 problems at Venus was to build a moon made of Carbon.

Using up 61 bars of Carbon to make a moon solved most of the catch 22 problems and created a new one, a mostly 02 atmosphere that would ignite.
It wasn't a giant problem, just more Carbon created to form a moon.

Reducing the nitrogen wasn't a big problem, it is pretty simple to fix nitrogen in many ways.

When Venus gets to around 3 bars we use a decent sized water/ice kb to add water and avoid the hydrogen import and heat created from bonding it.

Its pretty tough to guess at what Venus would do on any teraform attempt, things we expect to go one way might be totally different on Venus.

That slow spin does not help us at all in keeping local regions moderate so without a decent cloud cover it would be trouble on any Venus.

I'm guessing most of my data on what happens on Earth but a simple process might be very complex on Venus.
As you say Venus does have a moderate area in its atmosphere, so a good foot in the door to start something.

I agree on the water, it can be a very good or bad thing at Venus, all depends on the where and what form its in.

I also agree that high altitude clouds will help reduce temperature on Venus, so maybe some hydrogen import will be needed as a step towards something else.

Spatula · 2007-05-24 11:53:49

There are various ways of getting rid of the carbon that can be used in conjunction. Taking it off the planet is not a good solution. It needs to be there for organisms to utilize.

Floating photosynthetic microorganisms could fix it.

StarDreamer · 2007-05-25 08:50:52

Okay, so liquid water is a better heat sink than water vapour. How do you get liquid water on Venus? By precipitating it out of the atmosphere. How do you precipitate it out of the atmosphere? By dropping it from clouds. How do you get the clouds? By cooling the planet. How do you cool the planet? By making clouds. Can you see the problem here??

The issue on Venus s reversing the greenhouse, just as on Mars the issue is triggering the greenhouse. Any rain that fell from clouds on Venus would never hit the ground -- it would evaporate at about the 40-50km height. How much water would be needed to get this going? Would all the water on Europa be sufficient? Or Chiron or one of the other centaurs?

Bryan

Spatula · 2007-05-25 10:42:59

No cooling necessary for clouds. Those should form right away.

Antius · 2007-05-31 05:17:30

Yes, I'm creating a second thread when the first one is still active, kind of. I'm a bad, bad man who must be punished most severely. Be that as it may, brief notes written in reply to lengthy queries have a way of being lost in the shuffle when the threads go off on extended tangents, like the one about planetary migration.
Let's focus this one a little more narrowly. We've presented with the almost poetic image of cities floating in the Venusian atmosphere, I guess slowly drifting downward as centuries or millenia of terraformation convert a Carbon Dioxide atmosphere into a Nitrogen-Oxygen one, the cities coming down to a new earth out of a new heaven (and don't ask me where the Nitrogen is coming from, because I have no idea). A few Christian fundamentalists might be absolutely intrigued by the parallel with the image of the new Jerusalem in Revelations, but as much fun as we could probably all have with the subject of the cultural implications of all of this, one can possibly shoot the idea down in one word.
Convection.
The heat engine on Venus is going to be a lot more powerful than the one on earth, and I have to wonder what is going to happen to one of those floating cities when it floats into a downdraft. Yes, it has bouyancy pushing it back up, but one can say the same of any unfortunate swimmer who gets himself caught in an undertow. He still goes down. Any reputable studies done of how much force our meterological undertow (convection powered downdrafts) would place on those bobbing cities, and how far down one of those cities might drop?
In the Mars vs. Venus vs. Titan competition, this strikes me as being a good reason to favor Mars. Yes, Mars can get very, very cold, BUT one can build underground. In fact, given the reality of radiation levels on the surface pre-terraformation, one would probably have to do so. Rock makes an excellent thermal insulator, so even if the surface is frigid, it doesn't follow that a great amount of energy will be needed to keep a subsurface habitat warm, or that a power failure would rapidly throw everybody into the deep freeze. There would be the difficulty of getting sunlight down to any gardens beneath the surface, but if one is willing to build parasols the size of planets, building a series of reflectors to concentrate and collimate sunlight and then bounce a few ferocious sunbeams underground would seem to be a trivial enterprise by comparison.
One which, by the way, might very well be practical with present-day technology, or something very close to it, unlike that planetary parasol. The beauty of one's Martian burrow is that one doesn't have to worry about where it's going to go. Out of these three choices, my vote would definitely be for Mars.

I think the downside of any scheme for a floating Venus city is the same as many other schemes suggested on this forum. It is difficult to imagine why any government or private group, would go to the trouble or expense of creating them.

For colonising the moon there is a clear commercial imperitive; the export of materials to construct solar power satellites and orbital colonies for Earth. These are things that the moon can export and that people will pay for. It would appear a little far-out to most people, but there is at least a plausible mechanism through which it would happen and that would allow a lunar colony to pay for its imports. The same is true for Near Earth Asteroids.

For Mars, the commercial imperitive is weaker, due to its heavier gravity, atmosphere and distance from Earth, but it is still likely that following heavy colonisation of near-Earth space, independant groups would travel to Mars and set up home at some point in the late 21st or early 22nd century. Mars has enough accessible resources and a comfortable enough surfcae environment to allow the colonies to be relatively independant of outside support, beyond a certain critical size.

None of these arguements appear to apply for a floating colony on Venus. It's thick, poisonous atmosphere and deep gravity well, make it difficult to escape from; there is no plausible export that it could provide that could not be provided by the asteroids at a far lower energy cost and there is no realistic hope of terraforming it with any technology that we can presently contemplate. It would remain critically dependant on outside imports, with no plausible export to pay its way and would be a precarious structure at best, with difficult engineering requiremnets.

Spatula · 2007-05-31 09:28:24

I think the purpose of any sort of floating base would be primarily for terraforming. Nothing manned would be needed. Just automated facilities that grow and release bacteria that can sequester the thick CO2 atmosphere.

I wonder if it would be possible to set up a base on Maxwell Mount's summit (tallest mountain on the planet). It would be subject to far less atmosphere than the lower areas. Depends on the temperature.

Antius · 2007-05-31 09:55:06

I think the purpose of any sort of floating base would be primarily for terraforming. Nothing manned would be needed. Just automated facilities that grow and release bacteria that can sequester the thick CO2 atmosphere.
I wonder if it would be possible to set up a base on Maxwell Mount's summit (tallest mountain on the planet). It would be subject to far less atmosphere than the lower areas. Depends on the temperature.

Terraforming Venus with algae/bacteria is a dead duck from the start. What are you going to do with the trillions of tonnes of carbon and oxygen within the atmosphere? And where do you plan to get sufficient hydrogen and mineral trace elements to sustain the bacteria? Even if it were possible to reduce the carbon through organic processes, you would still be left with an atmosphere containing 60 bars of atomic oxygen and a mass of carbon sufficient to cover the planet to a depth of a hundred metres. Not an easy problem to solve.

The only plausible solution as far as I can see would be to completely block out the sun from the planet, allow it to cool to cryogenic temperatures (beneath the freezing point of nitrogen) and then simply fire the solidified CO2 into space electromagnetically.

It is uncertain who would want to undertake such a project and why. The cost of such large scale planetary engineering would be gigantic, the investment timescale measured in centuries or millenia, and unlike Mars, it would be impossible to terraform Venus in an easy and incremental way. If the solar system started running short of carbon in some distant point of the future, it might be possible to justify mining the Venusian atmosphere, with a potentially terraformed world as a long-distant side benefit.

From a financial viewpoint, it would be preferable to build a several thousand large O'Neill colonies, providing an equivelent surfcae area to Venus.

Spatula · 2007-05-31 12:06:48

Terraforming Venus with algae/bacteria is a dead duck from the start. What are you going to do with the trillions of tonnes of carbon and oxygen within the atmosphere? And where do you plan to get sufficient hydrogen and mineral trace elements to sustain the bacteria?

Redirect dozens of comets to collide with Venus, transferring oceans worth of water. Water is in surplus in the outer solar system, and already in its natural form. Gaseous Nitrogen? Generally in other forms. Every time you have to convert something, unless you can do it organically you'll be doing it very expensively. Especially when you're forming N-N triple bonds.

Even if it were possible to reduce the carbon through organic processes, you would still be left with an atmosphere containing 60 bars of atomic oxygen and a mass of carbon sufficient to cover the planet to a depth of a hundred metres. Not an easy problem to solve.

The carbon layer drawback occurs with a different method of terraforming, where you import straight hydrogen instead of water. You can avoid making loads of atmospheric oxygen with this method, since it's all converted into water. I was interested in this method for a while, but it seems like importing straight water would be thousands of times easier, and extra oxygen is not necessarily a byproduct.

The only plausible solution as far as I can see would be to completely block out the sun from the planet, allow it to cool to cryogenic temperatures (beneath the freezing point of nitrogen) and then simply fire the solidified CO2 into space electromagnetically.

This is very implausible, and it'll kill the planet anyway. The CO2 is important. We want to convert it into glucose and ATP. If we want to build a stable C-O cycle, we have to build a large biomass, similar to the one on earth. Achieving this is complicated, but if sufficient water is present in the atmosphere, we can give it a good start with photosynthesizing bacteria, that'll fix the CO2 in useful solid configurations. Phosphates, nucleic acids, and carbohydrates require a lot of oxygen and carbon, sticking to aerobic bacteria should skirt the '60 bars of oxygen' problem. Slowly, all of the atmosphere will become fixed in solid form as a bacterial 'lawn'.

We also want a bit of an oxygen surplus, relative to earth. Anti-greenhouse gases like ozone will play an important role in reducing atmospheric temperatures, and a lot of this stuff needs to dissolve in the ocean the comet-water will eventually form.

It is uncertain who would want to undertake such a project and why. The cost of such large scale planetary engineering would be gigantic, the investment timescale measured in centuries or millenia, and unlike Mars, it would be impossible to terraform Venus in an easy and incremental way. If the solar system started running short of carbon in some distant point of the future, it might be possible to justify mining the Venusian atmosphere, with a potentially terraformed world as a long-distant side benefit.
From a financial viewpoint, it would be preferable to build a several thousand large O'Neill colonies, providing an equivelent surfcae area to Venus.

I don't think you've quite thought out Mars to this extent. Getting enough Nitrogen to it is just one of a series of painful steps that require extensive mining and refining. It certainly can be done, and we might even start the process sooner, filling the atmosphere with CFCs and hyper-greenhouse gases. I think that the calmer surface conditions on the planet have created the illusion that the planet is closer to Earth chemically and just a few short steps to terraform.

This is not true. Venus is chemically very close to Earth in the interior, and close on the exterior as well, but lacking one ingredient, water, because the Sun's early growth cleared it from the inner solar system, and all the inner planets. All the water that accumulated on them is thus the result of cometary impacts, which occur more often on planets further out, like Mars and Earth, and less on the inner-inner planets, whose orbits were rarely crossed.

The thick toxic atmosphere is simply the natural form of all the life, oceans, soil, and crust on earth, if you took all the water out of them. Chemically remove it from every molecule in every cell, pull it out of the rocks, you'll get CO2.

Achieving ecopeiosis on Mars will be complicated, and ironically it will involve making a thick CO2 atmosphere so photosynthesizing organisms will sequester it. Unless you have better ideas.

nickname · 2007-06-03 07:35:06

Antius,

The only way i could figure out how to teraform Venus was to make a moon from the carbon.
Separate the C02 into C for the moon and use the 02 as primary fuel to get it to orbital location.

With that formula you have a decreasing atmosphere of both problem elements.

This process could be started small scale with 1 self replicating machine since we have so much free carbon to make things from, and so much free solar power for C02 separation.

The time scale and cost could be quite small as the replication of the initial machine will be exponential.
Maybe even much smaller than a Mars teraform.

Near the completion of the atmosphere reduction a couple of water/ice asteroids to add the much needed h20 to Venus.
Then simple chemical factories on the surface to reduce the nitrogen quantity to earthly levels.
Or plant peas and clover on the entire planet to reduce the nitrogen.

I think a completed Venus with a 1 bar atmosphere would need to have near 0 C02 in it's atmosphere, or it will be perilously near the boil point of water at the equator on hot long days on a very slow turning planet.
Maybe 3/4 of 1 bar would make Venus a somewhat earthlike place.
My guess for a teraformed Venus is lots and lots of rain due to the much increased evaporation cycle vs Earth, maybe 24/7 or whatever that is on Venus

dicktice · 2007-06-03 18:16:44

How about, as a thought problem, imagine what Earth would be like weather-wise, if it turned on its axis the way Venus does. Anyone?

Spatula · 2007-06-03 19:06:22

No more seasons, for starters. Venus is not tilted significantly with relation to its orbital plane. Perhaps retrograde rotation would reverse atmospheric currents?

Not sure what it would do to the number of cells. Probably nothing; I think that's more affected by the rotational velocity of the planet. It would cause temperatures in each cell to become stable. Much less temperature discrepancy between day/night than a planet with a stronger tilt. Something I imagine would be very helpful for a planet with long days.

Actually I suppose Earth's orbit would have very small seasons, since it's not completely circular, and varies over time. They would just be global, and last irregularly throughout the year. Venus's orbit is the most circular of the inner planets, so it wouldn't have that.

nickname · 2007-06-04 05:03:27

dicktice,

My guess.
An ice block.

Earth spinning backwards at such a slow rate would allow the ocean pointing away from the sun to freeze solid.
On the next rotation less ice would melt than has been produced due to the reflective color of the ice itself.

dicktice · 2007-06-05 17:56:16

dicktice,
My guess.
An ice block.
Earth spinning backwards at such a slow rate would allow the ocean pointing away from the sun to freeze solid.
On the next rotation less ice would melt than has been produced due to the reflective color of the ice itself.

Don't stop there. I didn't mean an alternative Earth. Just use Earth in place of Venus, to use what we know applied to "terraforming Venus." Would it even be feasible to sustain life with such a rotational configuration. (What could have caused it, by the way, and what a damn shame it turned out the way it did.)

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#51 2007-05-14 05:44:33

Re: Floating Venusian cities or Venus vs Mars vs Titan revisited

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Re: Floating Venusian cities or Venus vs Mars vs Titan revisited

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Re: Floating Venusian cities or Venus vs Mars vs Titan revisited

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Re: Floating Venusian cities or Venus vs Mars vs Titan revisited

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Re: Floating Venusian cities or Venus vs Mars vs Titan revisited

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Re: Floating Venusian cities or Venus vs Mars vs Titan revisited

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Re: Floating Venusian cities or Venus vs Mars vs Titan revisited

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Re: Floating Venusian cities or Venus vs Mars vs Titan revisited

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Re: Floating Venusian cities or Venus vs Mars vs Titan revisited

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Re: Floating Venusian cities or Venus vs Mars vs Titan revisited

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Re: Floating Venusian cities or Venus vs Mars vs Titan revisited

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