In terms of human habitation, the big advantages of Venus' atmosphere are:
1. It has essentially Earth-normal gravity. Zero-G long-term is a death sentence for humans. The long term effects of Martian gravity are unknown. It seems safe to assume that Venus gravity is fine.
2. It is protected from impact and radiation by an atmosphere in a way that Mars or asteroids never will be.
3. It has an essentially limitless supply of carbon, oxygen, nitrogen, and sulfur available to it.
4. It is reasonably well-positioned for solar power.
5. It is relatively temperate.
6. Low pressure differential between inside a habitat and outside of one means that leaks are less severe and containment breaches are easier to react to.
But there is at least one huge disadvantage:
1. Everything besides carbon, oxygen, nitrogen, and sulfur needs to be imported, either from a fantastically hostile surface, or down through reentry into an atmosphere in a deep gravity well and rendezvousing with an aerostat.
That disadvantage is a pretty goddamn significant one for human habitation.
But it's not a disadvantage for long-term robot probes, and it's... less... of a disadvantage for a minimal-population scientific base.
Mining the surface is required; importing any significant quantity of material from Earth is a non-starter. Unless you can come up with something insanely valuable to export to Earth, any planetary colony has to be almost-entirely self-sufficient. Interplanetary transit is too long, and too expensive. (This is true on Mars as well, and probably Luna and asteroids as well, though you might find some edge cases there due to lesser gravity or greater proximity.)
The pressure on the surface is that of about 3000 feet of water, so that's not too bad, and the reducing atmosphere can be handled, but the temperature is tough. Still, with practice, you could probably build such machines. Dunno how you make electronics survive long term at ambient 465 °C (oil wells have a hard time with electronics at much lower temps) but some combination of active cooling, limited duration, and novel fabrication should be possible.
Perhaps the easiest solution is to load up your Venus Mining Hopper with a whole bunch of liquid nitrogen, extracted from the atmosphere and compressed and liquefied using solar power falling on your floating platform. It deflates its balloon and drops to the surface, and starts scooping up material into its hopper as the LN2 boils off, cooling the electronics and other temp-sensitive systems. (These are buried in lots of insulation.) When the hopper is close to full, you start venting the N2 into the balloon, and the whole system takes off again, to rendezvous with a solar-powered tug to pull it to your ore-processing factory. That may be a long haul, because the upper atmosphere of Venus moves at 100m/s. Maybe you design your system to stay on the ground long enough for the platform to come back around the planet, a mere 4-5 days. Or maybe it just takes a big bite and goes straight back up so it doesn't get too far behind.
So maybe doable, but it makes the hurdle for setting up a self-sustaining colony much higher. Not that it's a much lower hurdle anywhere else.
The temperature is a reason why Venus would be a good place to test out the ideas for climate manipulation we have collected so far.
A first step could be to lower the CO2 content (my current favourite would be to release engineered bacteria into the atmosphere that can bind the Cs and after death collect it on the ground), and enhance the albedo (so more sunlight is reflected away).
In the longterm we will need climate control anyway since Earth's climate is somewhat unstable (global warming is just as bad as a new ice age, which, extrapolating from the past, would be about due by now, if not for mankinds influence). Testing it on a planet we are not critically dependent on should be a better strategy.
Geologically, Venus is very different from Earth due to the lack of water (which enables plate tectonics and all its implications). Some changes we can make would even influence the geology. (Hm, I wonder what would happen if we dumped enough water meteroids.. )
All of this of course premises a lack of preexisting life with planetary ownership rights and no natural reserve rules (which we kind of have at the moment - http://planetaryprotection.nasa.gov/about).
Please excuse the possibly stupid question, but what does water have to do with plate tectonics? I always thought that was a consequence of earth being a "live" (i.e. hot inside) planet.
The water in the interior is what matters. It's actually the fact that water is recycled into the Earth's deep interior that's thought to keep it "lubricated", so to speak, and allow the mantle to flow more readily. For the Earth, that's a feedback loop: water in the mantle allows plate tectonics to work, so water keeps getting recycled into the interior (via saturated crust and sediments) to keep it going.
What do you mean by "lubricated" exactly? The explanation I've had in classes for the "water is essential to plate tectonics" idea is that water causes dehydration melting, and that's thought to be critical to plate tectonics. Adding water to rock decreases the solidus temperature (temperature at which first liquid component is generated).
Yes, this is the current consensus of the scientific community. During subduction of plates (mostly oceanic crust full of water under continental plates of lower density) the volatiles (mostly water) exits the subducting plate and lowers the viscosity and density of the overlying mantle material (viscosity describing the 'fluidness' of the material, higher viscosity = less fluid). The material will then rise up and there will be volcanism, recycling the material back to the surface. This is what you see in most major volcanic arcs, such as the Andes or Japan.
The idea that plate tectonics and water are intrinsically linked (at given circumstances) is pretty solidified. The theory of why not such much; the idea above fits our current data best, but data from the planet's interiour is hard to come by and I expect some updates to the theory within a few decades. It's nice that this is currently not critical knowledge for humanity.
Note, this "water as lubricant" should not be confused with a creationist theory that tries to explain Noah's flood, suggesting that a huge portion of our current surface-water escaped at once.
Well, as a principle, anybody may try to claim rights/ownership over anything. The question that follows is how could that (no mater how far-fetched) given claim be further supported. Also, one way of securing good relations with others is to just recognize their claims.
Probably not, especially suitably advanced life, but we don't know. Our world is still very narrow. It's an ethical question that should be discussed before we destroy stuff. If the consensus was to go ahead anyway, that's fine too.
What about native Europeans, I mean the Neanderthals? They were the OG's before homo sapiens wiped them out...
It bothers me why we didn't just sit down on the edge of the world, as it is the Neanderthals, by the virtue of being there first (we call dibs!) who must have had planetary ownership rights to Earth. Not our usurping "natives".
You wouldn't steal a car, you wouldn't steal a handbag...
You can probably use half the arguments for vegetarianism here [1], and a lot more if there is sufficiently intelligent life (probably not on Venus; the argument is the same for other planets). Of course, not everyone agrees to those. Other extendable arguments include those for the preservation of species on Earth [2].
Your last sentence refers to the anti-copying campaigns, right? Since their analogy is so flawed, I don't see what you mean by that.. (Most people wouldn't steal a car, but they would totally copy one (as soon as they can).) If we could copy planets without disturbing orbit mechanics, there wouldn't be a problem?
[1] I'm talking about the ethics of using another species for one's own gain without dire need.
[2] For it's own beauty, but more importantly as a collection of ideas and examples for what is possible, as an information ressource, so to say. Since our state of knowledge is low, we cannot collect all the information without preserving the found state. Of course [1] also applies.
What ticked me off was this pretentious pseudolegal neologism of "planetary ownership rights". (No offence)
I would agree that humans should think twice - and some more - before damaging or contaminating an alien ecosystem, but that's even if it was only bacterial. Speaking about "ownership rights" in case of bacteria would be downright ridiculous.
Putting the entire moral problem under the category of "ownership" feels imposed to me. Not unlike the narration behind "copyrights" - and that's the association I hinted at. Not the idea of copying planets, although I can think of reasons why that would be your first guess.
If you put it like that, it does sound pretentious, haha.
I see why you might think it feels imposed. At this point it's probably more a problem of (loaded) word choice than ideas behind it. Thanks for clarifying.
Adding your point of view to mine, and taking into account the memes concerning planetary settlements I've aquired, ownership might be a bad word choice indeed.
Desertification, increased sea levels causing flooding, higher atmospheric CO2 causing ocean acidification that will kill nearly all life in coral reefs sans jellies, etc etc.
Global warming probably isn't inherently bad if spread out over enough time, but large temperature fluctuations within a few centuries doesn't leave time for non-human species to adapt.
> Desertification, increased sea levels causing flooding, higher atmospheric CO2 causing ocean acidification that will kill nearly all life in coral reefs sans jellies, etc etc.
Yes .. or Maybe .. but that all still sounds preferable to an ice age, if kaybe is right, right?
> Global warming probably isn't inherently bad if spread out over enough time, but large temperature fluctuations within a few centuries doesn't leave time for non-human species to adapt.
Eh, I don't know about that - you're not wrong but I don't think this is a relevant/useful consideration given that
(1) given that reasoning "spread out over enough time" everything and anything will work out fine
(2) in the long run (or rather the "even longer run", considering the first point) we're all dead anyways
Is there actual clear evidence that global warming has truly prevented an ice age? It's certainly the first time I've seen that assertion put forth and I'd need some actual scientific evidence that's the case.
I do agree though, an actual ice age would probably have a much more severe impact that global warming...but I'd definitely prefer that neither occur.
No, there is no clear evidence for that, unless you count models. It is all extrapolation founded in data - we have the temperature curve for the last few hundred thousand years (basically this: [1]), as well as information about the composition of the atmosphere. It is not even clear why and how ice ages happen exactly [2].
I'd not even be sure how to show evidence for that unless we waited a few hundred thousand years to make sure the temperature curve does not behave as before. I can, however, give some links to the discussions (e.g.[3][4]). The people in [4] ran a model, here's the paper: [5], and found a small effect (contact me if you can't access it). It's hard to say how good model evidence is, however. A lot of influences are missing, and we'd need to validate the model with more data, which isn't there. (So yeah, I wouldn't count that as evidence, just a hint.)
At this point, this is just an idea discussed by people with domain knowledge and experience, nothing more. It doesn't change the fact that we have a problem, it just influences how people look at details of climate models, and which questions to ask the models.
This is a great comment and I really appreciate you putting it together for me. I've read through all the links but can only read the abstract of the paper linked at:
Earth's surface is already 70% water, so lowering the sea level is better than raising it (coasts are productive, so 50% would probably be ideal); high temperatures also have implications for e.g. parasites (one possible explanation for why countries in cooler latitudes have been generally more successful than those closer to the equator).
You're right that cooling would be bad, and maybe a certain amount of controlled geoengineering through CO2 emissions would have been in order by now. But the level we currently have is past that, to the point where we're going to get far too hot, which is worse than being a bit too cold. If you're about to drive into a ditch then turning left a bit is good, but driving into oncoming traffic is worse than doing nothing.
Why not get other resources from near-Venus asteroids and Mercury? It would be easy to imagine a near-sun economy that mostly involves people, information, and raw materials making the trip up and down the Venusian gravity well -- with most raw materials and finished goods making the trip down. Most of the energy would be dissipated by aerobraking. In essence, Venus could participate in such a solar-system spanning economy by supplying relatively friendly radiation-shielded Real Estate and fluorine. Raw materials would largely go down, and people, culture, intellectual property, and fluorine would come up.
> Why not get other resources from near-Venus asteroids and Mercury?
The exact same reason we don't get our resources from near-Earth asteroids and Earth's neighboring planets: It's freaking expensive. One of the aspects that makes Venus attractive for colonization--similar surface gravity--also makes it expensive to launch anything. More-so, given that you'd be doing it with a frontier outpost's industrial base.
> Raw materials would largely go down, and people, culture, intellectual property, and fluorine would come up.
So why bother going to Venus at all, as opposed to creating such an economy around Earth? Barring catastrophe, Earth will certainly have a lot more people, culture, intellectual property, value-dense high-tech goods, etc., as well as significantly nicer/cheaper real-estate.
All successful colonies require an economic driver, and Venus is no exception. "Like Earth but less-profitable" is unlikely to do much.
> The exact same reason we don't get our resources from near-Earth asteroids and Earth's neighboring planets: It's freaking expensive.
Remember that I referenced its relative price. We don't get Earth's resources from near earth asteroids because we can get them more cheaply from Earth. Obviously, this wouldn't apply to Venus. Likewise, lots of things on the west coast of Alaska come from Seattle, not because it's cheap in absolute terms, but because it's the cheapest.
> So why bother going to Venus at all, as opposed to creating such an economy around Earth?
For the express purpose of not living on Earth. For the express purpose of spreading our civilization beyond the confines of one planet. Such an Earth independent economy and culture might be more likely to exist around Venus than Earth, simply because the proximity of Earth is more likely to pull investment away.
> All successful colonies require an economic driver, and Venus is no exception.
Not all colonies on Earth were motivated primarily by economics. People have lived in a variety of places on Earth motivated by religious and military concerns. Successful colonies will need economies to keep themselves going, but economic concerns are merely the strongest motivator for settlement, not the only ones. Granted they are in the minority, but there are people who live in the middle of deserts, in pressure vessels at the bottom of the ocean, in all kinds of remote wilderness, in many cases for the sake of living in such places as private citizens.
Granted, it will be a long time before such civilizations would begin to remotely rival the scale of Earth's, but I'm sure they will come to exist and that they will achieve near self-sufficiency.
Summary: People will live in space because they want to be there. Once a spacefaring population reaches a certain threshold, it will become self sufficient.
«"Like Earth but less-profitable" is unlikely to do much.»
1. Don't underestimate the human psychic. People are said to be rational, but we often come to surprise ourselves. As a joke, if you don't have sane/rational volunteers, just create a religion!
2. Don't overestimate the general conditions on our home planet. I hope I won't come to see it in my lifetime, but escaping from here could be similar (at least in sentiment) to escaping from one's home-town/home-country or worse. Things can always get worse in a lot of different ways, and then when comparing again, the Venus option could start to appear as a pragmatic one.
I have a hard time imagining Earth getting so awful that Venus looks like the better option. Even after an all-out nuclear war, it wouldn't be that bad.
This is what made the fundamental plot kicker of 'Interstellar' so daft. "Oh, we have a crop disease problem and dust storms? Clearly we must move the human race to another planet, even if it's a frozen hellscape with no breathable atmosphere." As opposed to, say, building some greenhouses, or ramping up aquaculture or aeroponics.
I have a hard time imagining Earth getting so awful that Venus looks like the better option.
The moving to the new world involved taking on all sorts of new risks, but people still did it for non-economic reasons. Instead of religious freedom, perhaps others will be attracted by the prospect of starting new civilizations or escaping oppression?
They moved to the New World. They didn't move to the middle of Antarctica or the bottom of the Mariana Trench, both of which are far more hospitable than Venus.
Make sure you're not stopping at absolute difficulty when you should really be thing about difficulty in the context of technological capability. The near-arctic is a remarkably hostile environment, but humans can live there and thrive with only stone age technology. We are far beyond the stone age level of technology. The number of places that private citizens can live is far expanded as a result. (There are actually people now who have privately-funded undersea habitats!)
The decision of some individuals to move from the british isles to N. America for religious reasons happened in a specific economic, geopolitical, and technological context. If the available vessels and navigation were poorer or more expensive, it would not have happened, and they would have done something else. You have to consider these things in their specific context.
So, given a strong enough desire for people to live "in space" or "on Mars" or "on Venus" combined with the technological and economic wherewithal to do it, people are going to try. Combine this with very wealthy national powers led by a class of engineer-technocrats with a demonstrated track record of implementing multiple decades long-term payoff projects (China) and the conclusion I come up with is that there is a significant chance that we will wind up with civilizations elsewhere in the solar system.
Also, the specific environment they're talking about in the article isn't anywhere close to the Mariana Trench. It's at about 1 atmosphere pressure. The most hostile thing about it would be constantly encountering sulphuric acid clouds. (This would also be a tremendous benefit, however.) Another important difference: The physics of building livable volume favors by far Venus human-aerostat altitudes over the Marianas Trench. Equipment for working "outside" in that specific Venus environment is something we already have a good idea about implementing inexpensively. The basic physics of the Marianas Trench makes doing the same down there orders of magnitude harder. Likewise, other basic physics around energy would preclude economically feasible agriculture in the trench, but indicates that it's quite doable at those altitudes on Venus.
A Venus colonist would probably sing songs praising PTFE. (One's already been written: "Polytetrafluoroethylene -- that's Teflon, you @ssholes!") Fortunately, we already know that one could condense fluorine directly out of the atmosphere of Venus with basically just energy as input.
I don't think I am. I can imagine high-tech settlers having a strong enough desire to move to orbit, or Mars, or the asteroids. I can imagine it becoming possible to survive on Venus, although the extreme shortage of water (it's what, 20ppm atmospheric?) would be a major issue.
I just can't imagine Venus specifically ever making it the top of anyone's list. Where's the plus to compensate for the many many minuses? It's certainly not the view.
the extreme shortage of water (it's what, 20ppm atmospheric?) would be a major issue.
Given enough energy, you can get water from the Venusian atmosphere. Granted, you basically can't have Venusian civilization without exploitation of space resources and having solved transportation costs to and from orbit, but water is not a hard barrier for a technological civilization.
Where's the plus to compensate for the many many minuses?
It may well become the cheapest place in the solar system to build human-habitable volumes. If you posit that there will be a solar system-spanning civilization in the first place, then physics and chemistry seems to suggest Venus has a lot of plusses in that particular context.
Granted, the only way that such a thing can come about could be properly termed sheer insanity. However, human history is practically made out of sheer insanity, chief of which can be called "nationalism". My money is on some power or powers at the scale of an industrialized nation-state eventually solving the problem of cheaply getting to and from orbit, motivated by the same sort of geopolitical insanity that motivated the Cold War. Given that, such a solar-system wide context of civilization will inevitably exist. All you need is one faction that makes it look like they might eventually establish such a civilization in their own image. Then competition will drive the rest. Look at it the other way: basically all such programs must 1) fail then acquire the aura of impossibility or insurmountability 2) forever remain out of the reach of private entities. It's entirely possible civilization may fall or some other circumstance would bring about those two conditions, but it's far from a certainty. Viewed in this way, completely earthbound humanity doesn't look like a stable configuration.
I absolutely agree with the plot flaws. I'm sure there are much easier ways to solve crop disease and dust storm problems. It'll probably involves alot of genetically modified crops and building dust proof houses.
> any planetary colony has to be almost-entirely self-sufficient.
Is this even remotely possible anywhere with current technology? Can we even make completely self-sufficient colonies on Earth (like the technologically advanced kind we want to make in space, not just people living in the woods.)
I don't think anyone's really tried, outside the Gingery books and such. (And even Gingery bootstrapping is just a machine shop, much less modern technological civilization.) Here on Earth we have to trade long distances to get raw materials anyway, so we might a well trade other things. Even in the most isolated areas, outside goods tend to leak in.
A new planetary economy would certainly have to be very tightly circumscribed in terms of materials and techniques, and even then I think it would be dismayingly huge, though modern techniques like 3D printing would help. It would be a worthwhile exercise just to plan such a thing on paper. Might make an interesting if overly-complicated game with sort of a Dwarf Fortress feel.
In Biosphere 2 the human volunteers ended up IIRC needing a few millilitres of liquid oxygen injected every 6 months or so. Perfect? No, and we'll probably never get to 100% perfection. But it's pretty damn close; if that was all you needed you could ship a big supply from Earth every decade or so, and it starts to look relatively affordable.
(Of course most parts of space are much more hostile than an Earth desert)
http://www.nytimes.com/1993/01/05/science/the-environment-ox... says "Project leaders, expecting the decline to continue, have made arrangements to pump tons of pure oxygen into the 3.15 acres of glass domes. ... "If we decided to raise the level by 2 percent, that would be 100,000 cubic feet of gaseous oxygen,""
A short ton (907.2 kg) of oxygen is 635 cubic meters or 24160 cubic feet as a gas and 794.5 liters as a liquid ( http://www.uigi.com/o2_conv.html ) so they would have needed 5 tons to raise the O2 levels by 2%. For what it's worth, the concrete depleted the O2 levels from 21% to 15%, so about 30 tons would have been need to fully restore the O2 levels.
800,000 mL/ton means that it was not the case that it needed "a few millilitres of liquid oxygen injected every 6 months or so." More like a few thousand liters every 6 months.
I was talking about the direct injections into the participants' lungs; I wasn't aware they'd also needed to pump oxygen into the whole thing. Thanks for the correction.
Self contained is also different than self sufficient. With a lot of carbon dioxide in the atmosphere, all you need is a good energy supply, then oxygen is easy.
(A similar example, some submarines use electrolysis for oxygen)
We probably could, but even in the most hostile and remote places on Earth it's easier to air-drop food and other resources than it is to grow and mine them. So there is no financial incentive to do so.
1g at 1 atmosphere has disadvantages. Namely: to get off the planet, you will need a fully fuelled multistage rocket with an almost identical profile to rockets you'd launch from ground level on Earth. Something like a Falcon 9. That's a bit heavy to lug all the way from Earth.
Bonus: you have to launch by dropping it into a hell-cauldron of poison gases miles above a crushing, melting surface, better hope you don't have an engine out, because there are no launch aborts or do-overs. Then you have to fly it out through a hot corrosive acid atmosphere which I don't imagine would be very friendly to machined aluminum.
Not quite an identical profile; it's not quite 1g, since Venus is less massive, and you're already quite a ways off the surface.
It's still not trivial, but it's not like there are a whole lot of do-overs when launching valuable human cargo from Earth, either. (What happens if the space shuttle's engines go awry? Everyone on board dies, and everyone on the ground speculates as to whether they died within 30 seconds, or survived to hit the ocean.)
The shuttle was an outlier, a rocket without an escape mechanism once the crude, firework-like boosters were lit, which relied on ultra-advanced, brittle and damageable heat shielding for re-entry because it had wings.
> 1g at 1 atmosphere has disadvantages. Namely: to get off the planet, you will need a fully fuelled multistage rocket with an almost identical profile to rockets you'd launch from ground level on Earth.
Condense Carbon Monoxide and Sulphuric Acid from Venus's atmosphere for use as fuel and oxidizer in a hypersonic rocketplane that tops out at about Mach 11. Have the rocketplane rendezvous with the end of a rotating tether.
No multi-stage rocket. No expendable launch vehicles. That's probably not the actual solution, but it shows that you don't have to have a Falcon 9 equivalent.
> Then you have to fly it out through a hot corrosive acid atmosphere which I don't imagine would be very friendly to machined aluminum.
It should be possible to condense HF out of the Venusian atmosphere, so we should be able to manufacture PTFE locally with input from non-Earth resources. (Mining chondrites from Mercury and Venus-crossing asteroids.)
Why not a space plane? Surely reaching orbital velocity on a platform that is already moving at a decent speed around the planet would ease it somewhat?
For the first problem, we can probably build small "launcher" platforms from lighter gases so it brings the spaceship to an altitude with much less gravity.
The sulfuric acids should be fine with enough protective coating. Earth's atmosphere isn't all that friendly either with rust able metals. Thus we have corrosion-resistant paint.
For the first problem, we can probably build small "launcher" platforms from lighter gases so it brings the spaceship to an altitude with much less gravity.
Uh, no. Sit down with the equations yourself. The main way one counteracts gravity is by gaining orbital velocity. Astronauts aboard the ISS experience almost as much pull from Earth's gravity as you do on the surface. It's that their orbital velocity puts them in a frame of reference that has "microgravity."
When I posit launcher platforms on Venus, the point is to launch from a higher altitude, thus avoid some losses to air friction, and also to use the entire station as reaction mass for launching the payload from an electromagnetic cannon. Doing this avoids the near-exponential nastiness of the rocket equation.
Why aren't people thinking about sending various robots/devices that could terraform planets before humans going in to live there? Is this something that is impossible to do/imagine? what am I missing?
Alternatively, why aren't we talking about venusforming humans? All space operas seem to start with the earth-standard human in a suit. Compared to geoengineering a whole earth-standard atmosphere, bioengineering an intelligent organism that can thrive in nonearth environments seems fairly sane.
There's a social taboo against human genetic experimentation (hell, some people seem to struggle with vegetables) but that will eventually pass.
That's if you wanted them to live on the surface, which seems to be a pretty tough problem to solve in any fashion. If we're contemplating living in the clouds, maybe a lifeform more birdlike or gasbag-jellyfish-like would make sense.
Granted, I'm not sure I would want to show up to a blind date with a human/portuguese man-o-war hybrid.
Plus ATP, the cell-internal energy distribution mechanism that is a property of all life on earth destroys itself at 52 degrees celcius. That means no controlled energy actions can happen in cells above 52 degrees celcius. We'd have to redesign every enzyme, every single cell function.
I am confused about your point. The original statement was "ATP, the cell-internal energy distribution mechanism that is a property of all life on earth destroys itself at 52 degrees celcius". I pointed out that thermophilic bacteria exists and reproduce at over 52 C. Therefore, there's an apparent contradiction.
Is your statement about "roll differently" mean that there is no ATP synthesis? Certainly not, as your link shows. Is your statement that thermophilic bacteria isn't alive? I strongly doubt it. What then does it mean to "roll differently" in the context of ATP presence being a requirement for all life on earth, and hence a 52C upper limit?
That sounds intriguing as well, but I can't seem to wrap my mind around the kind of knowledge needed to "venusform" a human. I have to say that the idea of sending a swarm of robots and setting up a bunch of chemical reactions seems less daunting (due to my lack of imagination, I presume).
Or just engineering some. Biological organisms seem overly tuned to their environment and complex ones need a supporting biological ecosystem to thrive (so far that we've seen). It may be more effective to get robotics to our level and expand intelligence into the galaxy 'synthetically'.
The line between "biological" and "synthetic" is blurry and gets blurrier all the time. You can (and probably should) see biology as super advanced tech. One of the primary benefits is self-replication - ability for components to consume various resources and build copies of themselves. This is huge, and it enables everything from self-regenerating materials to in-situ upgrades. 3D printing is a joke compared to that. So while maybe Earth organisms are a bit over-tuned (on the macro scale) to planet's environment, we'd do good to treat life as superior nanotech we don't control yet, and not some kind of joke that can be replaced with steel and silicon (not that you said that; it's just a point of view I often see on the Internet).
I don't get why more people don't think this way.
Humans as they are today will probably never be able to thrive in space or even on other planets similar to earth, that is without a lot of genetic engineering or something of that sort.
Create intelligent self replicating machines and a large part of the problems related to space travel just disappear.
If creating an AGI is possible I would be surprised if the universe isn't already full of artificial life.
once you've gotten to the tech level where you can artificially engineer a lifeform advanced enough to do something useful, but hardy enough to survive venus-
by that point I'd say the distinction between robot and organism would be pretty blurry. ;-)
"why aren't we talking about venusforming humans?"
We're all humans here on Earth and yet it seems that that is not always enough to relate on a personal level and keep a human attitude over each other in order to prevent destructive escalations and the risk of wiping out each-other in mass. Just imagine the dirty politics that would arise around the (hypothetical) results of your idea.
Even without deliberate intervention, humans in space and on other worlds will evolve quite rapidly if interplanetary intercourse--as it were--ever breaks down.
With the order of magnitude of resources we are talking about (enough to colonize) yes it would be impossible to terraform either Mars or Venus. People are thinking about it, but not in the near-term. I think that the easiest way to terraform Venus involves scooping a gas giant for hydrogen to burn with Venus' CO2.
> It has an essentially limitless supply of carbon, oxygen, nitrogen, and sulfur available to it.
Are you able to provide a rough summary of how the quantities of these materials compare with the quantities available on earth?
It wasn't that long ago that humans spoke about things like the number of fish in the sea, the ability of the earth's atmosphere to absorb waste gases etc as being effectively infinite until we eventually discovered that this was unfortunately not true. It is just something that pops into my head whenever the word unlimited, infinite or limitless get used when talking about energy, resources and so on.
As long as we're talking about one mostly self-contained city, resources available will likely be infinite from practical point of view. The problem with Earth is that there are 7 billions of us living now; our impact thus becomes significant.
It would be nice to hope so but I'm actually unsure. We are becoming more efficient with resource management because our resources are increasingly constrained. If those constraints are removed, over the course of a few generations, it would be easy to slide back to doing whatever is fastest and cheapest (might be the cleaner way, might not be).
> reentry into an atmosphere in a deep gravity well and rendezvousing with an aerostat.
What about rendezvous of a rotating tether with a hypersonic craft? We can make cables now that are strong enough to support a "rotorvator" rotating tether at the lengths required. What about very large, very long, aerostat facilities that are mostly huge electromagnetic cannon for launching robot hypersonic craft? These could be built to withstand 1000's of gravities, to allow ballistic launch from high altitiude facilities, but have a return flight profile suitable for passengers and other fragile cargo. We could also have Venusian hybrid jet/rocket hypersonic craft that are fueled with liquid carbon monoxide. This technology could mean that getting to the colonized Venusian ecosphere would be a lot cheaper than getting off of it, if you are a biologically standard Homo sapiens.
EDIT: So, how this would play out in a cyberpunk space opry: Many people choose to emigrate to Venus because of the price of labor there. However, economic pressures cause a large fraction of the Venusian populace to undergo radical cybernetic modification, because it opens up job opportunities on the hostile surface and makes it less expensive to get back to Earth and other parts of the Solar System. This pathway is chosen by desperate and marginal people, who often take advantage of the radical modification surgery to shed their old identities. Voila! Gritty Sci-Fi cyberpunk future based on chemistry, physics, and economics.
EDIT: It turns out that the energy cost for getting between Mercury and Venus isn't so large. Also, there are a good number of Venus-crossing asteroids. So anything you can get from a carbonaceous chondrite asteroid shouldn't be precious to the point of rarity on Venus. Among other things, both silicon and hydrocarbons could be mined in industrial quantities.
EDIT: An interesting idea for surface resource extraction -- bombard the surface with rocks from orbit, with the intention of creating clouds of dust which can be harvested by specially designed airships. Though this is inefficient materially, it might result in far less wear and tear on equipment, which gets to remain at higher and friendlier altitudes.
EDIT: Carbon monoxide and sulphuric acid can be used as a fuel/oxidizer pair in a rocket engine! Both can be condensed right out of the Venusian atmosphere. Granted, these are a bit cantankerous even as far as rocket fuels go.
Your disadvantage 1 is the result of a failure of imagination. The vast majority of life on Earth is built from nothing but carbon, oxygen,nitrogen, hydrogen, etc., and human life requires not much else. We could easily subsist on just these elements.
Note that "hydrogen" lists among your rather crucial elements necessary for life, and does not feature in Venus' atmosphere in significant quantities.
And, more so, while human life per se requires very small amounts of non-carbon, oxygen, and hydrogen elements, human technology requires very large amounts of non-carbon, oxygen, and hydrogen elements.
AFAIK, sulphuric acid is present in the Venusian atmosphere in large enough quantities to cause obscuring clouds. Though, I imagine that equipment to harvest the hydrogen from those clouds would end up being quite expensive. (Given my limited chemistry knowledge, I'd guess that large amounts of silicon would be involved in their manufacture.) There are also significant amounts of hydrogen sulfide. (Which could be quite a complication for human settlers as well.)
EDIT: FTFA -- "Moreover, while both planets boast ample amounts of volatile life-sustaining materials like hydrogen, carbon and nitrogen, only Venus’s dense atmosphere would be helpful in shielding human colonists from the harsh assault of solar radiation."
'Subsisting' does not include 'artificial cities floating in the sky'. Similarly, getting a computer to run on nothing by carbon, oxygen, nitrogen, hydrogen and sulphur, none of which are metals or semiconductors, is a massive task, if doable at all.
I don't think getting things from Venus orbit down to human friendly aerostat altitude is going to be an insurmountable problem. When sending things into the Venusian atmosphere, you can always take advantage of aero-braking. Then, the aerobraking equipment can itself be taken apart and used.
Running an economy on mostly carbon, oxygen, nitrogen, hydrogen, and sulphur would make for an interesting hard sci-fi book!
Any real colony needs to be mostly self sufficient (hopefully entirely self sufficient) so the problem is not getting materials down from orbit, but up from the surface.
In a far-seeing, long term analysis, I don't think we should limit "colonies" to discrete heavenly bodies. Long term, we should consider the complex of Venus, Mercury, and Venus-crossing asteroids as a local resource pool.
The notion that a single planet has to be largely self-sufficient as an independent unit is a bit of prejudice that comes from our upbringing on Earth. On Earth, in terrestrial economic terms, it's generally relatively expensive to get things off the planet and back onto its surface in one piece. For this reason, we think of planet Earth as a practical (if not absolute) boundary for economic transactions and resources. In the larger context of a solar system spanning society, it's costly in absolute terms by current-day Earth standards, but in the larger context, it's also relatively cheap to ship things down into the Venusian atmosphere from Mercury, Venus-crossing asteroids, and even Mars. In fact, one can make it materially inexpensive by applying lots of energy, which shouldn't be nearly as expensive by that point.
It's probably true that Earth's gravity well will limit trade of material goods between itself and the rest of the solar system. But there's no reason that a solar system spanning culture couldn't exist as a largely separate entity. I suspect people will live out there just for the idea of it, and that nation-states will help in the endeavor just to propagate their own cultures.
Right. History is full of land-based powers that didn't realize they needed a navy until they enlarged their context. This just involves an even larger new context.
Sure.. except, nature has conveniently put those elements into forms we can use. So until we're able to do that ourselves, that's a disadvantage we'll have to deal with. It's less a failure of imagination, and more a failure of our current level of technology.
1. It has essentially Earth-normal gravity. Zero-G long-term is a death sentence for humans. The long term effects of Martian gravity are unknown. It seems safe to assume that Venus gravity is fine.
2. It is protected from impact and radiation by an atmosphere in a way that Mars or asteroids never will be.
3. It has an essentially limitless supply of carbon, oxygen, nitrogen, and sulfur available to it.
4. It is reasonably well-positioned for solar power.
5. It is relatively temperate.
6. Low pressure differential between inside a habitat and outside of one means that leaks are less severe and containment breaches are easier to react to.
But there is at least one huge disadvantage:
1. Everything besides carbon, oxygen, nitrogen, and sulfur needs to be imported, either from a fantastically hostile surface, or down through reentry into an atmosphere in a deep gravity well and rendezvousing with an aerostat.
That disadvantage is a pretty goddamn significant one for human habitation.
But it's not a disadvantage for long-term robot probes, and it's... less... of a disadvantage for a minimal-population scientific base.