Writing Science Fiction Novel about living above Venus in the near Future! Need help with Science!

[Andrew Zachary Foreman]

5 minutes ago, Scotius said:

Everything possible. You should get it by now - if you can't bring the materials from the space (asteroids, other planets and moons), and you can't mine it on Venus, carbon extracted from the atmosphere is the only building material you will have in relative abundance. Carbon fibers, fullerenes, graphene, nanotubes - your colonists will have to use them for everything. From hulls of the habitats to tableware, shoes and hair combs.

And this would actually be doable? Can you foresee any problems that would arise from trying to use carbon to meet most building needs for several decades? 

[Scotius]

I don't know - i'm not an engineer or materials scientist. But currently we do build car chassis, boat hulls, fishing rods and motorcycle helmets out of carbon components among many other things. Read a bit about it - it's fascinating.

[Andrew Zachary Foreman]

11 minutes ago, Scotius said:

I don't know - i'm not an engineer or materials scientist. But currently we do build car chassis, boat hulls, fishing rods and motorcycle helmets out of carbon components among many other things. Read a bit about it - it's fascinating.

I will. Thanks for the suggestion!

[radonek]

11 hours ago, Andrew Zachary Foreman said:

They would be very intelligent, yes. It is assumed that initial colonists would have to be vetted. It is very important for the plot of the book that they cannot access outer space. Do you have a better suggestion for what would hold them back?

Well, its easy to imagine any number of technical difficulties to keep them down. But that would only make them work harder to restore orbital capability. I gather you want them content with their situation.

12 hours ago, todofwar said:

You have a very optimistic view of humans. Human nature doesn't change, I think superstitions and fear can creep in easily. Without necessarily compromising their ability to run the ship. Hell, at a certain point it will be more about knowing the intricacies of the ship, not the derivation of the laws of buoyancy.

No, I have pessimistic view of living inside artificial ecosystem midst of nonsurvivable environment. That kind of situations tend to have ways to filter out idiots. If colonists education somehow degraded to the point of just pushing right buttons, the would be unable to repair their own equipment, much less produce new one. So yes, they need to know laws of buoyancy, or they wont be able to check and repair their flight control equipment. Not to mention constructing new balloons. They need very deep knowledge of biochemistry and ecology to maintain biosphere. They need to know a lot about engineering to repair equipment, and much, much more to be able to produce new one. I have some doubts that several hundred souls can absorb that much of know-how. Other option is that you live knowing that certain critical equipment is irreplaceable and when it breaks, colony will die out.

11 hours ago, Andrew Zachary Foreman said:

I know almost nothing about how a geothermal system would work. I understand that Venus gets about 40% more solar energy than Earth, and if you assume that efficiency rates will have improved over the course of several decades it seems like the best way to get energy would be to focus on solar. What are your thoughts on that?

If you have cold and hot surface, you can produce electricity. Bigger the difference, more power you get. If earth provides you with hot or cold, its called geothermal, but it really works in any situation. This is how RTG power sources work - you have hunk of warm plutonium, a heatsink at ambient temperature, which is pretty low at space and thermocouples in between. On Venus, you'd probably lower down a heatpipe to pump heat from hot air below. but temperature difference is going to be much lower and heatpipe long and kinda heavy. Maybe lower a water tank, let it warm up, rope it back up… but that would be kinda complicated machinery.  I'd stick with solar - you need large balloons anyway, which gives you a lot of surface area. And photovoltaics could be made from carbon, which is renewable resource there. You could probably harness wind by throwing turbine into height different winds, but that is a lot of stressed moving parts - equals maintenance and replacement parts. Thinking about it, kites or sails on cables would be great way to anchor or move around without raising/lowering whole colony. 

 

Edited September 29, 2016 by radonek

[DerekL1963]

25 minutes ago, Scotius said:

I don't know - i'm not an engineer or materials scientist. But currently we do build car chassis, boat hulls, fishing rods and motorcycle helmets out of carbon components among many other things. Read a bit about it - it's fascinating.

Carbon - and a whole bunch of other elements that make up the resin.   Where do they get the other elements?

[radonek]

6 minutes ago, DerekL1963 said:

Carbon - and a whole bunch of other elements that make up the resin.   Where do they get the other elements?

Also, what are machines that produce them made of?
 

[DerekL1963]

4 minutes ago, radonek said:

Also, what are machines that produce them made of?
 

And the electronics that control those machines - what are they made of, and how are they replaced?

[todofwar]

1 hour ago, radonek said:

No, I have pessimistic view of living inside artificial ecosystem midst of nonsurvivable environment. That kind of situations tend to have ways to filter out idiots. If colonists education somehow degraded to the point of just pushing right buttons, the would be unable to repair their own equipment, much less produce new one. So yes, they need to know laws of buoyancy, or they wont be able to check and repair their flight control equipment. Not to mention constructing new balloons. They need very deep knowledge of biochemistry and ecology to maintain biosphere. They need to know a lot about engineering to repair equipment, and much, much more to be able to produce new one. I have some doubts that several hundred souls can absorb that much of know-how. Other option is that you live knowing that certain critical equipment is irreplaceable and when it breaks, colony will die out.

 

Don't forget, humans made most of our advances while believing in all kinds of superstitions. Newton thought there were secret codes in the bible, pythagorous was one part mathematician one part mystic one part cult leader. Superstitious belief and science know how are not mutually exclusive. 

[Scotius]

1 hour ago, DerekL1963 said:

And the electronics that control those machines - what are they made of, and how are they replaced?

This is the point i'm raising again and again - just read my earlier posts in this thread. A colony can't survive on Venus without an external source of materials. They'd have to bring it from other bodies, or from surface of Venus. If they don't do it, they will have very little to work with - carbon, sulphur, hydrogen and not much more. There is no way to keep machines going, computers working and people healthy, clothed and well fed. There is no way to get enough freakin' water! I rest my case

[kerbiloid]

3 hours ago, Andrew Zachary Foreman said:

What could I use carbon for?

Easier to list what for couldn't.

2 hours ago, DerekL1963 said:

Where do they get the other elements?

 

2 hours ago, radonek said:

Also, what are machines that produce them made of?

And where and what would they use if mining the mountain?

[peadar1987]

As others have pointed out, when people say stuff is made of "carbon", it isn't really. It is made of carbon composites. Either carbon fibres, or more exotic forms like nanotubes. These fibres are stuck together with a matrix, which is generally a polymer of some description, like poylurethane or epoxy. You can get carbon on Venus to make reinforcement, but matrix material is going to be very hard to produce.

[todofwar]

23 minutes ago, peadar1987 said:

As others have pointed out, when people say stuff is made of "carbon", it isn't really. It is made of carbon composites. Either carbon fibres, or more exotic forms like nanotubes. These fibres are stuck together with a matrix, which is generally a polymer of some description, like poylurethane or epoxy. You can get carbon on Venus to make reinforcement, but matrix material is going to be very hard to produce.

There is hydrogen on Venus, low amounts but its there as sulfuric acid, hydrochloric acid, and even some water. You can set up a cold trap and leave it running for a few weeks and you'll start collecting stuff that can be used. People freak out about acid, but you can store them in most plastics without too much trouble. Recycling would be the order of the day, and in this scenario new habitats aren't getting built so you only need to take in a few materials from the outside. You can use the water and CO2 to grow plants, and use the biomass as feedstocks for plastic production. Once the hydrogen is fixed as plastic, recycle until it has become too warn out, then burn it, trap the water, and keep it going.

People have been working for decades to use carbon based materials (organics) for pretty much everything. Organic transistors, organic solar panels, organic circuits. Unfortunately all the papers I might pull are behind pay walls, but really about 90% of things can likely be made purely of organic material in the next couple decades. Now, for earth based applications they are rarely as economical as the alternatives (silicon comes from sand, and the processing cost vs efficiency keeps pace with organic replacements). On Venus, such products can very easily become the order of the day.

Another way to mine Venus would be to not go all the way to the surface. Drop a line of something with a high melting point, maybe a steel chain or something, but you need a way to keep it cold. Lead sulphate and other things will sublimate and deposit themselves on the line, which can then be hauled up for processing once it gets to a certain weight. Not sure what all you will collect that way, I think the theory right now is its mostly lead, but there's probably other metal salts that will come along with it. Edit: lower the line to within a few Km of the surface, but you will need to keep the habitat well above this level. Will probably need a specialized unmanned airship for this purpose.

Edited September 29, 2016 by todofwar

[peadar1987]

Yes, it would be possible to get some trace elements from Venus' atmosphere. But you would have to process huge volumes of stuff to do it. That takes massive amounts of power. Extensive facilities. Huge industrial plants. You're not going to have that on a floating airship.

[todofwar]

18 minutes ago, peadar1987 said:

Yes, it would be possible to get some trace elements from Venus' atmosphere. But you would have to process huge volumes of stuff to do it. That takes massive amounts of power. Extensive facilities. Huge industrial plants. You're not going to have that on a floating airship.

Not really. Just a good filter. Just need to flow the atmosphere through at a high rate. You only need scale to serve the hab, not a civilization. People are picturing earth level industry, but that's for earth level needs. 

[Scotius]

We can't even get around to filtering useable elements out of sea water on a really industrial scale (well, except table salt) - where they are in much higher concentration (relatively speaking, of course). And you want to filter the toxic air of Venus to keep industry of this hypothetical colony going? OK, let's ask OP abouth the scale of things: @Andrew Zachary Foreman How many people you want to live in your colony? A hundred? Ten thousand? A million?

[todofwar]

14 minutes ago, Scotius said:

We can't even get around to filtering useable elements out of sea water on a really industrial scale (well, except table salt) - where they are in much higher concentration (relatively speaking, of course). And you want to filter the toxic air of Venus to keep industry of this hypothetical colony going? OK, let's ask OP abouth the scale of things: @Andrew Zachary Foreman How many people you want to live in your colony? A hundred? Ten thousand? A million?

I believe the scenario is a few hundred trying to survive Watney style, not full colony, but I'll let the OP reply. And to get things from the atmosphere is allot simpler on Venus. Because you just need to cool it down. For seawater, there's no good molecular scale filter right now, so you have to boil away the water and then sort through the tons of salt. For Venus, you just need a cold trap.

Gas goes in, water and acids condense out, gasses leave. It will take a while to accumulate things, but again you just have to make up losses not grow. Similar principle for collecting things like lead, they are in a gaseous state and you just need to condense them.

[DerekL1963]

1 hour ago, todofwar said:

For Venus, you just need a cold trap.

That brings up an interesting question...  where does the airship dump it's excess heat?

[todofwar]

4 minutes ago, DerekL1963 said:

That brings up an interesting question...  where does the airship dump it's excess heat?

The atmosphere. Temperature on Venus reaches reasonable temperatures pretty quickly, in terms of altitude 

Edited September 29, 2016 by todofwar

[radonek]

Couldn't one extract moist by piping hot, dense air upwards? Also, some bonus energy from thermal difference. If it were just enough to make operation sufficient, that would be great. How about making whole habitat vertical to make most of thermal/pressure differences?

3 hours ago, peadar1987 said:

Yes, it would be possible to get some trace elements from Venus' atmosphere. But you would have to process huge volumes of stuff to do it. That takes massive amounts of power. Extensive facilities. Huge industrial plants. You're not going to have that on a floating airship.

We are not talking an airship but damn floating city. Workshops, factories, farms… If colony is to be self sustainable, it have to be able to produce it own spare parts. That means either  very advanced technology (replicators, nanomachinery, etc…) or just plain industrial base. So yes, processing huge amount of outside air is exactly the thing in my mind.  I would even take it farther - process even more air, make lots of surplus water and use it as coolant for surface machinery. I would not dare to call it "mining", but if one could cool a probe long enough to grab something from surface, that would solve a lot of problems.
 

[Andrew Zachary Foreman]

Thanks again guys! This is a great discussion. Some of you were wondering about the population that the airship will need to support. Originally, I planned for around 500. From my limited research this should be enough to avoid unwanted genetic defects from sprouting out in successive generations. I had thought about splitting this number up on a couple of smaller ships, but that seems impractical now. So, unless it would simply be impossible, what would it take for five hundred people to survive at least six or seven decades with no outside help? It seems like the biggest concern right now is how to gather resources to meet needs. I will talk about this below on all of your separate points, but I will quickly list the different proposals now. also, please realize that none of these have to be mutually exclusive. 

1. Use a heat sink to gather and filter trace elements from the sky.

2. Mine from mountain peaks.

3. Make literally everything from organics.

4. Use some sort of scooping mechanism that extends a machine down near the surface that could collect metals and then be towed back up. 

6 hours ago, radonek said:

Well, its easy to imagine any number of technical difficulties to keep them down. But that would only make them work harder to restore orbital capability. I gather you want them content with their situation.

No, I have pessimistic view of living inside artificial ecosystem midst of nonsurvivable environment. That kind of situations tend to have ways to filter out idiots. If colonists education somehow degraded to the point of just pushing right buttons, the would be unable to repair their own equipment, much less produce new one. So yes, they need to know laws of buoyancy, or they wont be able to check and repair their flight control equipment. Not to mention constructing new balloons. They need very deep knowledge of biochemistry and ecology to maintain biosphere. They need to know a lot about engineering to repair equipment, and much, much more to be able to produce new one. I have some doubts that several hundred souls can absorb that much of know-how. Other option is that you live knowing that certain critical equipment is irreplaceable and when it breaks, colony will die out.

If you have cold and hot surface, you can produce electricity. Bigger the difference, more power you get. If earth provides you with hot or cold, its called geothermal, but it really works in any situation. This is how RTG power sources work - you have hunk of warm plutonium, a heatsink at ambient temperature, which is pretty low at space and thermocouples in between. On Venus, you'd probably lower down a heatpipe to pump heat from hot air below. but temperature difference is going to be much lower and heatpipe long and kinda heavy. Maybe lower a water tank, let it warm up, rope it back up… but that would be kinda complicated machinery.  I'd stick with solar - you need large balloons anyway, which gives you a lot of surface area. And photovoltaics could be made from carbon, which is renewable resource there. You could probably harness wind by throwing turbine into height different winds, but that is a lot of stressed moving parts - equals maintenance and replacement parts. Thinking about it, kites or sails on cables would be great way to anchor or move around without raising/lowering whole colony. 

 

So solar is still the way to go? How would using kites and sails work? Like a glider in our own atmosphere? 

 

4 hours ago, Scotius said:

This is the point i'm raising again and again - just read my earlier posts in this thread. A colony can't survive on Venus without an external source of materials. They'd have to bring it from other bodies, or from surface of Venus. If they don't do it, they will have very little to work with - carbon, sulphur, hydrogen and not much more. There is no way to keep machines going, computers working and people healthy, clothed and well fed. There is no way to get enough freakin' water! I rest my case

So if the atmosphere simply can't provide what is needed, what do we do? It seems like going down to the surface would be even harder.

 

4 hours ago, kerbiloid said:

Easier to list what for couldn't.

 

And where and what would they use if mining the mountain?

Any equipment that would be used to mine resources from the mountain peaks would be extraordinarily heat and pressure resistant. The problem is that I don't know if this is plausible. 

 

3 hours ago, todofwar said:

There is hydrogen on Venus, low amounts but its there as sulfuric acid, hydrochloric acid, and even some water. You can set up a cold trap and leave it running for a few weeks and you'll start collecting stuff that can be used. People freak out about acid, but you can store them in most plastics without too much trouble. Recycling would be the order of the day, and in this scenario new habitats aren't getting built so you only need to take in a few materials from the outside. You can use the water and CO2 to grow plants, and use the biomass as feedstocks for plastic production. Once the hydrogen is fixed as plastic, recycle until it has become too warn out, then burn it, trap the water, and keep it going.

People have been working for decades to use carbon based materials (organics) for pretty much everything. Organic transistors, organic solar panels, organic circuits. Unfortunately all the papers I might pull are behind pay walls, but really about 90% of things can likely be made purely of organic material in the next couple decades. Now, for earth based applications they are rarely as economical as the alternatives (silicon comes from sand, and the processing cost vs efficiency keeps pace with organic replacements). On Venus, such products can very easily become the order of the day.

Another way to mine Venus would be to not go all the way to the surface. Drop a line of something with a high melting point, maybe a steel chain or something, but you need a way to keep it cold. Lead sulphate and other things will sublimate and deposit themselves on the line, which can then be hauled up for processing once it gets to a certain weight. Not sure what all you will collect that way, I think the theory right now is its mostly lead, but there's probably other metal salts that will come along with it. Edit: lower the line to within a few Km of the surface, but you will need to keep the habitat well above this level. Will probably need a specialized unmanned airship for this purpose.

I'm interested by this idea of almost "scooping" resources from near the ground. Wouldn't you have to at least within 10 km of the surface by that point though? And if you could do that, it seems by that point you might as well just mine mountain peaks. 

 

1 hour ago, todofwar said:

I believe the scenario is a few hundred trying to survive Watney style, not full colony, but I'll let the OP reply. And to get things from the atmosphere is allot simpler on Venus. Because you just need to cool it down. For seawater, there's no good molecular scale filter right now, so you have to boil away the water and then sort through the tons of salt. For Venus, you just need a cold trap.

Gas goes in, water and acids condense out, gasses leave. It will take a while to accumulate things, but again you just have to make up losses not grow. Similar principle for collecting things like lead, they are in a gaseous state and you just need to condense them.

Right, growth isn't important, just maintaining the statue quo. 

[todofwar]

@Andrew Zachary Foreman the idea is that on Venus it snows lead because the temp is so high lead sulphate can sublimate (go from solid to gas). Presumably other metal salts do the same, I purify metal compounds by sublimation all the time. Even tungsten will sublimate when bound to the right things. The idea is instead of scooping tons of rocks that need to be refined, you can go in blind and condense out the metals and bring them back with you. No drills needed, no need to longer on the surface for too long. 

[radonek]

1 hour ago, todofwar said:

I believe the scenario is a few hundred trying to survive Watney style, not full colony…

No, OP wants sustainable colony whose inhabitants are content where they are. No outside contact, much less rescue.
 

[Andrew Zachary Foreman]

1 minute ago, todofwar said:

@Andrew Zachary Foreman the idea is that on Venus it snows lead because the temp is so high lead sulphate can sublimate (go from solid to gas). Presumably other metal salts do the same, I purify metal compounds by sublimation all the time. Even tungsten will sublimate when bound to the right things. The idea is instead of scooping tons of rocks that need to be refined, you can go in blind and condense out the metals and bring them back with you. No drills needed, no need to longer on the surface for too long. 

That sounds great! How would the process work and how heavy would it need to be? 

[todofwar]

3 minutes ago, Andrew Zachary Foreman said:

That sounds great! How would the process work and how heavy would it need to be? 

Not sure. You just need a cold bucket basically, things should deposit into it. Google iodine deposition to get a visual of what to expect. 

[DerekL1963]

32 minutes ago, Andrew Zachary Foreman said:

Thanks again guys! This is a great discussion. Some of you were wondering about the population that the airship will need to support. Originally, I planned for around 500. From my limited research this should be enough to avoid unwanted genetic defects from sprouting out in successive generations.

The people I know who've thought deeply about this all think that the real bottleneck isn't genetics - it's occupational specialties.   A colony of 500 might only need a neurosurgeon once every two years or so for example...  where does he get his training and experience?  Etc... etc...  With sufficient and proper tech this can be hand waved away of course, but it's something to be aware of.  (The numbers I've seen tossed about to avoid this bottleneck are in the five digit range.)