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Mars Problems vs. Venus Problems (interconnected.org)
159 points by headalgorithm on Sept 23, 2020 | hide | past | favorite | 202 comments

Let's terraform the Earth.

No, I'm seriously you guys.

We have just figured out that we can (re)make forests out of deserts, let's do that. Let's do the hell outta that!

"How to Grow a Forest Really Really Fast" https://news.ycombinator.com/item?id=9074473

Search on "Greening the Desert" E.g. https://en.wikipedia.org/wiki/Desert_greening

"Celebrating 10-Years at the Greening the Desert Project, Jordan" https://www.youtube.com/watch?v=yI9wMtTvWps

This is a regenerative process: the forest produces the seeds, fauna, and materials needed to create more forest.

We can totally do this, and many people are, the tricky bit is getting the economics to work.

"Terraform Earth" is a great slogan for a 'bright green' viridian approach to our interlocking ecological crises.

We're already doing it, after all. But we don't think about it in those terms, and we aren't getting the kind of results which we might, if we did.

What you're proposing we can call silviforming, and it's a good idea. We spend too much energy making Earth more like Mars (dry and barren) or like Venus (a roiling greenhouse of carbon dioxide inimical to life); let's make Earth more like Earth instead.


And it's really an economic puzzle, the life-forms work automatically (4Byr old self-improving nanotech).

The Syntropic Farming guy grows the best cocoa beans on the planet at 3x the yield of comparable-quality conventional farms with no fertilizer nor irrigation, and he's getting other crops out of the same "food forest" too. The production is there, it's a matter of getting the word out and engineering the economics.

I think a combination of Small Plot Intensive (SPIN) farming with the soil-building "Grow Biointensive" system makes a good "wedge" for small holders to make money, which you can then parley into food forests. (A food forest takes a few years before it starts to really cook, the SPIN/GB market farm covers the gap.)



(BTW, to anyone reading this, if you're near San Francisco and want to get into this let me know. I'm gearing up to test this out.)

> 'bright green' viridian approach

Is this a reference? I don't understand what this means.

Ah, the late, lamented Viridian movement!

Bruce Sterling tried, with some success, to promulgate a technologically-oriented and optimistic approach to the climate crisis, around the turn of the millennium.


That article, conveniently enough, contains a link to one on "bright green environmentalism", which bruces considered similar enough that he closed the chapter on the Viridians.

Which, I wish he hadn't. But I can't fault him for finding other things to do with his time.

Thanks for that. Also just wanted to say I love your writing style, even though these were both pretty quick comments.

it probably has to do with solarpunk.

Now that you mentioned terraforming Earth, let me mention my favorite forgotten mega projectL Antlantropa (https://en.wikipedia.org/wiki/Atlantropa). Peel away the colonialism, ties to Lebensraum, and lowering the Mediterranean by some 200m, the man-made lakes to irrigate Sahara is an interesting idea, I think! Boosts Africa's untapped potential. On a similar vein also see the Qattar Depression Project (https://en.wikipedia.org/wiki/Qattara_Depression_Project)

I like how nature environments have "untapped potential" if they're inhospitable to humans, even though they have tons of interesting/diverse creatures and fauna. Like, all the earth is here for is to squeeze out a few more acres of corn to raise beef

While Atlantropa is a silly idea, and lowering the level of the Mediterranean Sea is an invitation of disaster, the current through the strait of Gibraltar is quite substantially powerful, and most of the energy involved is currently dissipated. Without damming the strait or lowering the level of the Mediterranean, and with limited disruption to the ecosystem an enormous amount of stable hydropower could be generated there. The geography of the Mediterranean basin is really an incredible opportunity, that concentrates the Sun’s energy throughout the whole basin at the Strait.

(disclaimer, I work in a Climate R&D group)

Please don't do this.

Deserts are great at shedding heat into space (high albedo in the visible, high emissivity in the infrared, low humidity). Climate feedback loops are complicated.

I'm skeptical that the net effect of a desert is better than the net effect of a forest. I understand exactly why deserts are useful, but I can't imagine they're more useful than forests.

Forests continuously sequester carbon as trees grow, live, die, and the microbes which feed off the dead trees ones grow, live and die. The cycle of carbon utilization is never totally efficient, and the carbon that is "lost" in the cycle blackens the soil.

Plus, you get biodiversity as a bonus.

No, you are correct, it's just complicated and broad applications of afforestation will require very accurate modeling. The perceived benefit will depend on what timescale you care about.

Changing the albedo and local transpiration has an immediate effect (which can be positive or negative, depending on the existing albedo, downstream effects, etc). CO2 sequestration, on the other hand, takes time.

If you plant trees, let them grow for 30 years, then remove a high fraction of that carbon from the cycle (e.g. lumber), then the break-even point can be pretty short (decades, probably, but I don't have a good number). This will depend on a lot of climate feedback effects, like heat leaking out of your forest through moisture evaporation (which otherwise would have been shed back into space), what the existing carbon uptake rate was of the location you planted (did you replace scrubland, grassland, desert, ...?), etc.

If your permanent sequestration is primarily due to carbon cycle efficiency loss, maybe multiply that timescale by a factor of 10-50.

here's a great article on creating ice in the desert:


not only does the desert shed heat into space, it makes makes it possible to create ice due to this action. amazing.

Trees chemically capture some of the incoming sun energy. Are you certain the radiation cooling through that infrared atmospheric window takes away more energy than what’s trapped in carbohydrates? We have technology to keep that energy trapped for hundreds of year (wood paint).

WHat you're saying sounded counter-intuitive at first but it seems to make sense when you think about it.

If we could turn the major deserts into forests it would be like putting on a wool coat on a hot day?

How does this desert greening stuff differ from the earlier "Rain follows the plow" [1] idea?

Seems fundamentally similar, though maybe with some better understanding of the dynamics.

[1] https://en.wikipedia.org/wiki/Rain_follows_the_plow

It works.

(Culturally, it's not coming from a colonist mindset. This is about regenerating land that never should have been desert in the first place. Jordan wasn't always desert, for example.)

We are on a trajectory to increase the average temperature of the planet by as much, if not more, than from the last ice age to now, when so much of the oceans were frozen than the sea level was 120m lower than it is today and northern Europe and America were covered with several kilometers of ice. And so within one century. When we reach that point forests won't even be able to grow. That's the scale of problem we should be facing. The ideas you propose are just a distraction.

I don't understand, maybe I'm misinterpreting your position.

Based solely on the scale of the problems yourself presented, you must surely agree that (mega)engineering is the most factible solution in terms of time. Greening the desert might be the best idea but the scale certainly sounds right.

The only solution is to stop releasing CO2. There is nothing else that will save us. How much desert would we need to "green" to compensate the emissions? Where do we find the resources to do so, knowing that we must also cease to emit more CO2?

That's certainly part of the solution, but not the whole picture. Even if you stopped pumping CO2 today, 1) global weather processes have already started,. 2) the rest of the already pumped CO2 is not going to magically dissapear. It will take time, time we don't have.

The only actual solution is to engineer many solutions, supported by reducing the pumping CO2 at a minimum, hopefully zero.

My smartphone can't establish a connection with my Bluetooth headset if a phone communication is already taking place.

Leaders of some of the largest and richest countries on earth denied there was a Covid problem and still deny - or fake to deny - the climate crisis.

There's going to be a transition to something else but our specie or civilization isn't ready to make it smooth and I have little hope we can handle global scale projects like terra-forming.

Most likely there won't be any significant terraforming initiative and small scale local solutions will be enforced when it's too late for anything else.

It may be economically feasible if land in the Sahara were sold, under some reasonable terms like not polluting it beyond some reasonable level, on a 500 year lease to wealthy individuals who want some "effectively sovereign" land to try experimental forms of government.

I'm having a hard time interpreting your comment as anything other than "Let's sell kingships to the wealthy," and am not seeing how that would solve any problems at all.

It's not a kingship because it's only a 500 year lease. It could probably be shortened to 200-250. Enough time for very long term returns on investment.

500 years is longer than most royal dynasties lasted. In China, none of the CE dynasties lasted that long, in Ancient Egypt, no dynasty lasted longer than 300 years, and in Western Europe, off the top of my head, I can think of only the Capets and the Habsburgs who lasted longer.

The duration is not the issue that I have with the idea. Jonestown only lasted for 3 years, but caused some rather big waves with its experimental forms of government.

Effectively sovereign is pretty much already the deal in some countries if you're rich enough..

The only problem with Sahara is that no one will bother - there's also not much to govern except sand. If people wanted to spend billions to seed the place I don't think any of the government in Africa is going to say no, it's just that nobody is doing it.

Effective sovereignty requires an army when useless land becomes valuable

Changing earth's albedo can cause unintended consequences.

Then we really should stop doing it. And work towards reverting the reduction of ice and snow in glaciers and on the poles.

The solar radiation at the poles is much smaller than at the equator, so the contribution of polar ice to the total radiation-weighted albedo of the planet is much smaller than the contribution of equatorial deserts.

When the radiation happens, the sun ain’t shining anyway. What matters is the surface temperature, and the difference doesn’t look too bad, around 15%: 300°K in tropics, 250°K in arctic.

High albedo is important because of its effect on the net reflectivity of the planet, not its effect of the radiation of the surface.

Emissivity is the material property involved in radiation loss, and ice is highly emissive, but so is almost anything non-conductive. Also radiation loss depends on T^4, so that 15-20% difference ends up being closer to one being double the other.

The Sahara has grown something on the order of 10% over the last century [1]. So ~200 million of its 2.2 billion acres are new. Wouldn't we just be restoring the albedo to what it was?

[1] https://www.livescience.com/62168-sahara-desert-expanding.ht...

Yes but there are many knobs to play with, and if you make one change it better be a calculated one.

Mao thought that sparrows ate people's grain, so ordered to kill them all. What Mao did not know is that those sparrows ate vermin such as crop-eating insects. Those insects ate all the crops triggering the Great Chinese Famine, and the ecological disaster that requires farmers to pollinate plants by hand.


I've wondered about the feasibility of transporting the abundant CO2 in the Venus atmosphere to Mars for the purposes of terraforming both planets at the same time.

It's been a while since I've done the the envelope math but if I recall correctly there is more than sufficient CO2 on Venus to provide an atmosphere for Mars the issue is just transportation.

The last time I thought about it I considered some sort of massive floating solar powered comet builder that would cool the atmosphere into large chunks of dry ice that could then be wrapped in a metal sabot so that the comet could be accelerated to mars via a mass driver.

As with everything in space and terraforming the key is scale so the equipment used would need to built in situ out of carbon from the Venusian atmosphere.

We are of course still a ways away from mastering self replicating carbon based engineering but the idea of terraforming both planets at the same time is neat to me.

I love this idea, but there is something missing: nitrogen. You need to extract some of that from Venus as well, and bring it with you.

But if you really want to have fun with terraforming you should make Venus earth-like. I suggest an exciting starting point: build a solar shade at the Lagrange point and block the sun. That would eliminate most of the hard problems with Venus temporarily while we did whatever work is needed to get it spruced up. CO2 freezes to dry ice below -80C or so. You could let through just enough sunlight to get the atmosphere at a pressure humans can survive- then all we need is warm clothes and an oxygen tank.

Once Venus is in that state, the problem is simpler- how to get all the carbon and oxygen separated so that the carbon stays in some kind of solid form.

Oh, and we'll want to go get a load of hydrogen, likely from Jupiter, to mix with that Oxygen to form water. Your fleet of transports moving CO2 to Mars needs to make a detour on the way back.

Edit: fixed a word and also lol, just start with building a planet-sized solar shade, says some a-hole on the internet.

You still have to spin up the planet. An earth-like atomosphere would freeze solid on the dark side, and air from the light side would be rushing into the dark side, where it would freeze, until the light side was stripped of its atmosphere too. So the atmosphere would just be a mobile ice cap on the far side, rotating around the planet once per year, with the only gaseous atmosphere being a small, constantly-moving region of sublimation at the terminator betwen the light and dark sides.

Make the atmosphere thick enough to not freeze on the far side, and it'll be absolutely boiling on the near side. The slow rotation means that there is no happy medium: either you've got an atmosphere freezing solid, or you're cooking half the planet at any given moment.

> You still have to spin up the planet.

Do we? I think what you really want is to equalize the amount of solar radiation hitting all sides. And if I can build a planet-sized solar shade, well, why not go one step further and instead make a swarm of mirrors in orbit?

When they orbit the sun-facing side, they reflect the light away from Venus. When they're opposite, they're in darkness anyway. But when they're in between, they reflect light towards the dark side of the planet!

I choose the angle of every mirror in this swarm, and thus I choose the amount of solar radiation hitting each point on the planet at all times. Thus, Venus shall have one timezone, Venus Standard Time, and I swear to you it shall not have anything like Daylight Savings Time.

Not necessary, but convenient. Venus has very little water, so maybe impacting comets at the equator in the right direction would be enough to solve both problems

That would take more than a few comets. And it might, somehow, make Venus even less livable.

I read once that to slow Earth's rotation down to a stop, you'd need to perfectly sling 6 or more moons at it.

In the short term, probably. Not all energy from those impacts will be transferred to angular momentum.

Maybe blowing up the comets before they reach the atmosphere and giving them a larger impact area could help.

If you can build a planetary solar shade, engineer blue-green algae to survive the harsh conditions, and as soon as the temp on any part of the planet drops to survivable, seed the algae. It'll explode, sucking up the carbon.

Reactionless drives would be so nice.

Not only could you transport materials around, but you could make Venus spin in 24 hours in ~10^4 years using currenr Earth electricity output and a super-conducting emDrive -- I did the math a couple years ago.

Reactionless drives are indeed nice and really really dangerous - they make Earth shattering relativistic projectiles a bit too much easy to pull off.

Pair one such drive with a nuclear reactor and have it fly away from the sun for a while and then back - it will hit ludicrous speed on the way back, likely a good fraction of C. And there is hardly anything that can be done to prevent that as it needs just energy to gain speed, not bulky inefficient reaction mass.

There's really no substitute to mind-uploading when it comes to defense against kinetic stuff.

Yep - the ultimate solution fo many dangerous sitations - make the people in danger more robust or ideally effectively immportal. Solves a lot of issues & makes otherwise very complicated safety measures into much simpler ones.

There's really plenty of reaction mass around though. Could probably get it done quicker by having a few large drone ships that harvest reaction mass from the planet or nearby asteroids.

I would love to see an economic analysis of this. How many billions for the solar shade array, for example. How many years until the planet becomes livable with an oxygen tank. How many people would pay to live on Venus, and so on.

Solar shades the expensive way (as in right now, launch from Earth): https://www.youtube.com/watch?v=6yqi0FabHHs

After kickstarting a Lunar economy so you can manufacture and launch them well outside Earth's gravity well: https://www.youtube.com/watch?v=gOr-Gd58zu8

All this effort just to get sick at the bottom of another gravity well... Surely there's a nice moon of jupiter where the slippers would be a bit cheaper?

Need some damn heavy slippers there I guess. Compared to the radiation environment there, earths van Allen belts are a walk in the park.

It’s almost as if we’ve been given a planetary system with an ideal set of building blocks to get to the next phase of life. But instead we’re going to choose to destroy the planet we currently have.

Mars is probably not geologically active and has no protective magnetic field, so my first thought was to change that by hitting it up with a larger asteroid from the belt, preferably a metal rich one with significant mass. I first thought about its moons, but they are too small. I mean to achieve a complete planetary melting.

That would be step one, step two would be waiting a few million years and see how it turns out.

Such a cataclysmic event isn't necessary. https://phys.org/news/2017-03-nasa-magnetic-shield-mars-atmo...

The bigger issue with this idea would be getting enough hydrogen to Venus to create oceans. That would require hitting Venus with comets or possibly extracting hydrogen from a gas giant which seems impractical.

If you can extract materials from a gas giant it is probably best to just live around the gas giant. Short term Venus looks more amenable to life, though.

The radiation would be a significant problem.

142 comments and this is the only one mentioning ionizing radiation. Are you and I missing something that everyone else already knows?

That depends - where does energy come from. If we never figure out fusion, then it may be we can find the energy to extract a few materials, but not enough to live there long term. Depends on the material - a large platinum (very rare, the industrial need per year is greater than the total production in a century so industry makes do with something not as good) would be worth it, while iron is everywhere on earth so not worth it.

We already produce a significant quantity of ruthenium, rhodium and palladium in spent nuclear fuel and choose not to extract them. If these metals became more widely available the market price would collapse, which now would not justify both mining or nuclear reprocessing.

Going to space to mine a nickel-iron asteroid would be out, for very much the same reason.

Going to space to mine a nickel-iron asteroid makes a lot of sense, because the material is then already in space and you can use it for orbital manufacturing without having to pay the energy cost of getting it out of Earth’s gravity well.

I specified platinum for a reason. High value, and high potential demand. I believe that if supply expanded price would go up as industrial processes switch. (diesel catalytic converters would be better with platinum, but total world supply covers less than 10% of all diesel engines so they use alternatives)

The lighter platinum group metals are widely used as catalysts to produce large-volume chemicals. Off the top of my head there's methyl acrylate, vinyl acetate, acetic acid, many more.

Rhodium is especially scarce, palladium not so much, but it's a political metal, a substantial part of world production is not in the West.

Rhodium use would go up were it more available, lots of interesting chemistry there, and political security is also worth a lot, but extraction from nuclear reprocessing isn't happening. That's the intersection of politics and the markets, where markets become political.

Could we extract hydrogen from the outer planets and just shoot it at Venus? I.e. no tanks and transport ships, just a well-aimed jet of gas.

In principle, you could ionize the hydrogen and then accelerate a proton beam in the direction of Venus. But I think Venus has an active magnetic field powerful enough that it would be deflected off into space. Plus, accelerating mass out of the gravity well of a gas giant would be extremely energy intensive. Better to go looking for sources that aren’t at the bottom of a giant gravity well.

Why not let it cool off away from a plasma phase before hitting Venus?

I suppose you could fire a proton beam and an electron beam so that they would intersect before reaching Venus.

The problem is it is too far from the local star, so it's cold there.

This is sounding a lot like the Golden Age series by John C Wright. By the time when the novel's take place, they have cleaned up the solar system of all dust and comets/meteors

I say we sacrifice Enceladus to our Mars god.

If Hollywood taught me anything, it's that drilling into the stopped core and setting off nukes are the best way to get it started again.

I'd rather do that in a different solar system. Massive planetary collision like that is bound to have some unintended side effects.

What abput a world house instead ? https://www.orionsarm.com/eg-article/460e7e5f4977b

You basically start by building a roof over part of the surface, then you pump it full of breathable atmosphere and inhabit it. Then another part and so on until you have covered the whole surface or got bored by it. A huge benefit if that you can get (localized) results almost immediately instead of pumping massive resource into regular terraformation for possibly hundreds of years to only have useful results at the very end. Also you can do this on worlds that would never hold an atmospere (Moon, asteroids) or would loose it over time (Mars).

This is a common myth based on a misunderstanding of scale in the original facts. Yes, the atmosphere will blow away, but it takes millions of years.

As humans, we only have to top it off every hundred thousand years or so.

The magnetic field isn’t really a human scale problem. My understanding is that it takes on the order of a billion years for the solar wind to blow away anything but a hydrogen atmosphere.

Uv will break water and the solar winds will blow the hydrogen away. You'll need a lens to push the protons inwards so the don't blow the atmosphere away.

What water? Atmospheric or ground,? it still seems this would be a multi million year concern.

Atmospheric. We'd need a lot of water vapor in the atmosphere to power a greenhouse effect.

No,no! If you ram a giant asteroid into Mars, you will destroy all of it's crust, there will be no geology ir way to answer the question - was there ever life?

General rule: don't lift anything out of an Earth-class gravity well that you can get from a shallower dimple in spacetime.

Carbonaceous asteroids are pretty abundant, and Mars has oxygen in great quantity. The asteroid belt is also much closer to Mars than Venus is.

Nitrogen seems to be the building block that's a bit scarce. Venus definitely has some, but it's unclear that it's the first or best source to tap.

> Carbonaceous asteroids are pretty abundant

Phobos should have plenty of carbon too, and it's not really far from it. IIRC, it's close enough that with our current tech, we could build a "space elevator" there, that drags in martian atmosphere.

I’m sure the Martian crust has plenty of carbon to form an atmosphere. It’s a very common crustal element, and extracting it in situ is going to beat out any approach that involves transporting material through space.

There was actually a recent video from PBS spacetime on YouTube that did back of the envelope math on just this subject. The result is that you would basically have to strip mine the top three meters of the entire surface to get enough carbon, and the energy required for the chemical reaction would be something like 100 years of today's global energy production.

Sounds substantially easier than any approach that involves moving a similar amount of mass up the Sun’s gravity well.

You don’t really need to move “up” necessarily, right? You can drop “down” but into a more elliptical orbit that shoots far enough out to intercept Mars.

Moving "up" or "down" still requires you to change your velocity, which costs energy.

Did you mean a skyhook?

I still feel the best bet for terraforming Mars is deorbiting ice asteroids. They are already available and already solid. Can provide co2 or water depending on asteroid type. Still need a source of N2.

I think the first step is to cool Venus down. A giant parasol in heliosynchronous orbit (a bit inwards to compensate for the push light and solar winds give) seems to be the way to go.

Mars could require less mass. I'd go for a charged ring structure diverting protons from solar winds and focusing them into a spot on the surface to replenish the planets lost hydrogen and directing electrons towards the the edges so that the atmosphere would slow them down.

Imagine the autoras. After the sun sets, you'd see all those electrons plunging through the atmosphere and screaming in blue agony as they lose speed by hitting the CO2 molecules.

If you could connect a long hose between the two planets, you could use it as a siphon :)

I have a better idea: push Venus to an orbit between Earth and Mars and wait a little until Venus cools down a bit.

Oh shoot. What about a long and flexible Archimedes' screw?

If anyone finds this stuff interesting I can’t recommend Issac Arthur’s channel on Youtube enough. Regular out-there content on Megastructures, terraforming and the fermi paradox always grounded in real physics.

A space elevator that lifts chunks of atmosphere up till they freeze, and whips them towards Mars from the rotational velocity at the top?

A space elevator is too hard to build on Earth. I doubt insane temperatures and sulfuric acid rain makes it easier.

A sky hook might still work for this - an aitship based launch loop or RAM ion engines.

I love the thought. I also love the line of thinking here. I feel bad for having very different, mundane thoughts around getting rich with my next side project!

Mars' atmosphere is also 95% CO2. It's the pressure that makes the temperature so high in Venus, not CO2 concentration.

> It's the pressure that makes the temperature so high in Venus, not CO2 concentration

No, it's the partial pressure of CO2.

I think the crushing atmospheric pressure at the surface makes us think about Venus in the wrong way and leads us focus on the wrong things.

Consider that for a very large portion of the earth's surface the crushing pressure makes it damned difficult to get a probe to the surface, and we already have the advantage of starting 5-6 miles away.

And while I realize Venus isn't an ocean world, comparing it to our oceans does open your eyes to the idea that a focus on the surface, that is sea floor, ignores where a lot of the interesting stuff is going on.

Of course there is still the temperature and the sulfuric acid . . .

There's a really high mountain, 11 km, on Venus. Unfortunately still not very pleasant: "Due to its elevation it is the coolest (about 380 °C or 716 °F) and least pressurised (about 45 bar or 44 atm) location on the surface of Venus."


> 44 atm

Note that humans can and do work at higher pressures than this.

From your link mate:

> These only seven dives to more than 300 m do not include the dives of professional saturation divers using a divers bell at constant pressure for the transfer from surface to ground and back. These seven dives are done with decompression in the water not using a divers bell and saturation diving.

The selected answer is talking about huge pressurisation changes in a short amount of time, that's a very different situation and nothing like what commercial deepdivers do.

Saturation diving involves weeks of adjustment in a bell.

Much of the science suggests we haven't even come close to pushing the physical limits but no one is willing to risk it, the world record was set 30 years ago.

Work ? Maybe a diver can stay inert or do some small movement at 500 m but picking up rocks maybe not

More than 28 hours of work was done on the deepest saturation dive ever made, it was beyond your 500m mark:


Goodness, the number of folks who divide the world into "solved problems" and "problems to be solved" missed the entire point of the article. This article was not about "what we can do to the world for our own needs"; it's about "how can we change our minds and perspectives (our selves) to do the work that needs to be done."

I think people miss the point of the article because the article itself doesn't make much sense.

The opening paragraph states that scientists have found Phosphine and what conclusions they have draw about it (aka possible life). The next paragraph starts with the author stating, I quote, "I'm skeptical". The reason given that a mars rock that got scientists all excited 90's turned out to be a dead end. Come on. Then the author rambles on about how unfeasible it would be to explore Venus compared to Mars as if that has anything to do with life on Venus.

>I think people miss the point of the article because the article itself doesn't make much sense.

Perhaps that's so. It certainly doesn't directly address scientific issues with the exploration/exploitation of Venus and/or Mars.

Rather, the main theme of the blog post seems to be: The challenges of exploring Venus/searching for life are metaphorically similar to current issues here on Earth (climate change, SARS-Cov2, etc.), while Mars represents the endless expansion/frontier attitudes of 18th-20th century mercantilism/capitalism.

As such, I found the post to be more about how humans think about solving problems and a plea for a new kind of thinking. As Lincoln put it: "The dogmas of the quiet past, are inadequate to the stormy present. The occasion is piled high with difficulty, and we must rise -- with the occasion. As our case is new, so we must think anew, and act anew. We must disenthrall ourselves, and then we shall save our country."

While I certainly don't disagree with the sentiment, I'm not convinced that the metaphor is a good one. Exploring/colonizing/exploiting off-world resources, regardless of where they might be, will require us to "...think anew, and act anew."

All that said, perhaps I completely misunderstood the blogger's point. But I don't think so.

Edit: Clarified the amount of sense I think the author of the blog post was making and cleaned up my own verbiage/reasoning.

(Post author here)

That's a good summary of what I was trying to say, and I appreciate the effort you put into deciphering my rambling style. This wasn't a post I expected to get much attention!

Hey, sorry about my knee-jerk reaction to your article. Makes more sense after reading the above post! Looking back it was well referenced, I just went down the wrong thought path. I should think about things more before commenting. :)

Thank you for writing it. Not enough of this sort of thinking on HN. Too much emphasis on the incrementalism of "pioneering the obvious". Not enough on the 10,000 foot view of the problem.

"Pioneering the obvious". What an intriguing phrase! I wish you would expound a little more.

Terraforming is all nice and future oriented, but when I look at us rather failing to terraform Earth, I'm a bit more skeptical about our capacity to keep the climate on a different planet in check.

Good point. I guess the difference is here on earth we have to coordinate the behavior of billions but with mars it may be one united group of people.

Perhaps, but I think more likely it will have to be coordinated by a few nations. Which is easier, but can still be troublesome.

The best candidate for terraform on Earth is probably the Sahara but there are multiple wars going on there right now.

On the other hand, we have efficiently terraformed the hell out of Earth to increase shareholder profit.

Of course long term habitability might suffer but hey, thats a problem for the next generation.

Personally, I think I enjoy greater habitability than my ancestors of 150 or 1500 years ago did.

Do you enjoy greater habitability or do you use technology to compensate for habitability? Using air and water filters to offset for pollution we've added to the natural environment, for instance.

We all do. Our grandchildren likely wouldn't enjoy their level of habitability much though.

It always blows my mind when people say nonsense like this.

> On the other hand, we have efficiently terraformed the hell out of Earth to increase shareholder profit.

No actually we have terraformed earth so people could live comfortably, have heating in their home and ability to move around and many, many other things. And this continues because people in China, India and Indonesia and others would like to have these things too.

Unter a socialist government (assuming it would be able to consistently grow) where 'sharehoolder profit' don't matter you would equally have polluted the and terraformed the earth.

Casting this as some 'greedy elites' abusing the 'good people' is a fundamental misunderstand of the situation.

> There was a great paper in JBIS in April: Conceptual Design of a Crewed Platform in the Venusian Atmosphere (abstract only). It summarises two comprehensive studies of how to float crewed scientific missions in the clouds of Venus. The mock-ups look like a cross between dirigibles and the space station. Alien.

I don't see the point of a crewed scientific mission like these to Venus's atmosphere, except to claim the credit for just having sent humans there. It seems like accepting a lot of risk for very little gain, since, unlike Mars, it's not like there'd be any complex manipulation or interaction with the environment to do there.

The British Interplanetary Society (JBIS is their journal) has a great history of publishing the first engineering studies for grand projects -- crewed Moon missions (1938), geosynchronous satellites (1945), interstellar missions (1973), and more:


I agree with your general point (why send humans when robots will do?) but the engineering feasibility studies push the envelope of what we can imagine -- and reveal where more work is required. I tend to read JBIS from that perspective.

> I agree with your general point (why send humans when robots will do?)

That's not my general point, actually. I'm generally supportive of sending humans on exploration missions, but blimps on Venus seems off. It's like a manned mission down into the lava pool of an active volcano. Sure, maybe you could actually do it, but there's little point to do so except for the bragging rights.

If humans wanted to visit the atmosphere of Venus, it seems a lot safer and more practical to do it in a supersonic rocket plane. Then you don't have to worry about launching a manned return rocket from a dirigible.

It's not just about bragging, we are pretty sure that there aren't any life on Mars but Venus is another story. All we know is that the temperature is too high even for earth extremophiles but that's not an actual observation of the absence of life like on Mars, it's a conjecture. No entity has ever looked around on Venus for more than a few minutes and nothing has moved even 1 m at the surface. Venus won't have the potential for economic wealth like Mars colonization may have but at one point we will have to look and confirm scientifically if there is life or not.

I see. Yes, in the paper the scope was set to be model it on the space station: there's a habitable zone of the atmosphere about 50km up, and the mission parameters were to base there for ~10 years with multiple human/robot missions to the surface and a rotating crew. Other approaches (such as a supersonic plane) weren't considered.

Unfortunately the cited paper from OP is paywalled, further dragging down humanity. Anyone know how to find it on Sci-Hub?


You could make the same argument about the ISS, yet it exists and we send people there all the time. A research station in the atmosphere of Venus would, naturally, study the atmosphere of Venus. If we ever ran out of things to research while there(unlikely) then it would simply be abandoned, just like the ISS will be one day.

The ISS is primarily a jobs program, and secondarily a way to maintain our manned spaceflight infrastructure in case we ever decide to leave LEO again. The scientific research is barely an afterthought.

I consider it an excuse for Russia to keep their rocket scientists employed after the fall of the soviet union. Nobody wants a starving rocket scientist driven by desperation to take a job designing ICBMs for some evil dictator.

There is definitely some truth to this statement but, uh, it's been a while

Well that's demonstrably false we have not maintained manned spaceflight capability. It's an orbital laboratory. The only one we have.

It's more important to preserve the infrastructure rather than actually maintaining organic manned spaceflight capability. If we have all the infrastructure intact then the capability can be spun back up in a few years just by increasing funding. But once the industrial base disappears then it's effectively gone forever.

The ISS is orders of magnitude cheaper, safer, and closer to home. The experiments done there could be done by robots/craft or by launching humans in individual tin cans but at greater expense and higher failure rates.

I’d love to see humans afloat on Venus, but I tried really hard to argue with the grandparent and I can’t really see what humans bring to the equation that a decked out sensor array wouldn’t do for significantly cheaper other than simply humans being at Venus and learning how to keep humans alive at Venus.

humans are more flexible. They can look around and see interesting things and change plans to look at that instead. This is both good and bad - sometimes interesting things are more interesting than the plan, sometimes they are commonplace and the plan would have been better. Humans can often figure out on the spot how to put a tool to use for some completely different purpose.

A human on mars controlling the rovers would have explored a lot more than the rovers did - assuming they survived as long as the rovers have (this assumption is probably false even if we could get humans there - humans are fragile in ways robots are not)

Mars makes sense. There’s an environment they can interact with and a tool in a human’s hand is superior to a tool in a robot’s hands. For instance if nothing is found at six inches, a human can dig to twelve inches, but a robot might not be equipped for that. I’m struggling to see any scenario where humans-in-bubble-with-sensor-array is superior to sensor array when talking about the Venusian atmosphere. You can potentially respond to things in seconds rather than minutes, but I don’t think that’s a reasonable trade off for the risks and costs.

> humans are more flexible. They can look around and see interesting things and change plans to look at that instead.

That's true, but that doesn't matter so much floating in the Venusian clouds. Making a manned blimp has zero advantages over a robot blimp controlled from a space station. The only thing a manned blimp would have over a robot one is the humans could potentially do unplanned maintenance. However, the cost of that is orders of magnitude more complexity and cost over a robot blimp (life support and rockets to get back into orbit) and a hard deadline to end the mission. You could probably send five robot blimps or more for the cost of a manned one, which could potentially remain operational long past their design life. Send them one or two at a time, so ad-hoc modifications can be made.

It's really a no-brainer to chose options besides human exploration of the Venusian atmosphere.

If anything, research station orbiting Mercury would make more sense as a base for solar studies. Not to say it's mostly metal and silicates, thus a perfect base for a space shipbuilding.

I could agree with a compromise - a research station in orbit, and then mechanised exploration and 'settling' of the atmosphere itself.

If there's any chance at all now that Venus might have life, I'd think it worthy of about the same amount of funding Mars missions have had in their search for organics.

Atmospheric Venutian [life] could be very interesting and potentially very useful. If it's found to exist in any way, I'd not be too surprised to see an entirely privately-funded* mission in a couple of decades. Venus is energetically cheaper to get to versus Mars too.

I think it's a compelling target - 'Tomorrow's Antarctica'. You've got to have people there to do the science stuff.

- ed

* as in Biotech etc funded.

I don't see living on Mars (or Venus) getting desirable anytime soon, even for communities most affected by climate change. As it stands right now, it is still way easier to fix problems on Earth than to set up a small colony on Mars. Not that we shouldn't do it - it's an extremely cool science experiment but I find it a bit facetious when Elon and Bezos imply that Mars is the backup plan in case things get too screwed up here.

Its a backup plan for humanity, not individual societies or people. There are many things that we can not get a way from however many of earths problems we solve. Even without climate change or any human made problems, nature could kick us out any time for reasons we don't even know about.

Musk has two companies, Plan A, help not destroy earth. Plan B, inspire people and create backup.

Bezos doesn't want to go to Mars, he want people living in space and have the earth be a nature park of sorts.

Right. When they're saying backup plan I guess they're talking about the super-rich and powerful who could move to Mars while culling the herd here so as to make space for more agriculture and industry to enable the settlements to thrive. They're not taking about the billions.

Did someone imply that because of climate change the environment on Mars would be more hospitable to human life than Earth?

Potentially dumb question, but I keep reading that the average surface temperature of Venus is 450C and so completely hostile to life, but didn't we discover recently that the poles are much colder? [1] Aren't there thus regions on the surface with similar temperatures to earth?

[1] https://astronomy.com/news/2016/04/esa-finds-a-frigid-surpri...

The polar _atmosphere_ is colder than expected[1]. According to Wikipedia, the coldest point on the surface is 380 degrees C.


Ah ok that makes more sense... 380C is still pretty toasty.

It's 2 or 3 times what we use for "sterilization", if there's life it really loves the extreme

That's not quite how degree-based scales work.

In Kelvin we see it's about 1.5x as hot.

Or if you look at distance from "comfy" (25 C) to "dead" it's about 3x as far as dead from comfy so the conclusion still works .

I think the comparison was to 0..100C - liquid water on Earth surface.

Boiling point depends on atmospheric pressure. On Venus (93 bar) melting point is about 0C [1] and it boils at 305.6C. Interestingly under pressure "water becomes less polar and behaves more like an organic solvent such as methanol or ethanol" [2].

[1] https://en.wikipedia.org/wiki/Pressure_melting_point

[2] https://en.wikipedia.org/wiki/Superheated_water

The other place where life could exist is in the upper atmosphere where apparently temperatures are much more hospitable. There's a really good write-up with more information here [1]. On earth there exists microorganisms that live in our atmosphere so one hypothesis to explain the phosphine is that there may be a similar situation on Venus. I believe its also been theorized that we could build floating cities on Venus [2] given the climate in the upper-middle atmosphere.

[1]: https://www.reddit.com/r/Andromeda321/comments/ismnrb/venus_...

[2]: https://en.wikipedia.org/wiki/Colonization_of_Venus

In fact the atmosphere of Venus is the only place outside of Earth where humans could walk outside with just a simple oxygen mask - about 50km above the surface the temperatures are around 0-20C and pressure of one atmosphere. No other celestial body in our solar system has anywhere like that. But it's just like this article correctly identified I think - floating cities on Venus are not as cool as "normal" cities on Mars.

> the atmosphere of Venus is the only place outside of Earth where humans could walk outside with just a simple oxygen mask

The clouds of sulfuric acid might sting a bit.

> floating cities on Venus are not as cool as "normal" cities on Mars.


> floating cities on Venus are not as cool as "normal" cities on Mars.

For me floating cities are much cooler.

> the atmosphere of Venus is the only place outside of Earth where humans could walk outside with just a simple oxygen mask

Surely a bit of an exaggeration? The mostly carbon dioxide, 1 atm of pressure area is not bad, but it coincides with the thickest cloud coverage. The clouds which are composed of sulfuric acid.

Sure, so add a formfitting and thin fluoropolymer suit to that.

We could survive, maybe. But Cloud City would simply reek of rotten eggs, at all times, you'd never escape the stink of it.

Aside: Humans acclimate to the consistent smell of sulfure dioxide pretty quickly.

Which is fortunate, because some parts of the country have iron-eating bacteria in their water supply, which produce SO2.

New arrivals always notice though!

Re: Venus, unfortunately H2O + SO2 is a bigger problem than the smell of rotten eggs.

Well, except for the 'walking' bit, it being 50km above the surface.

A new novel by Derek Kunsken called "House of Styx" explores in detail human habitation of Venus. In floating cities and airships and realistically dealing with pressures, temps, and the acidity of the atmosphere.

Did you enjoy it? I really liked The Quantum Magician (puppets!) but thought The Quantum Garden was not a worthy follow-up.

I assume the atmosphere microorganisms on Earth started in a terrestrial tidal pool though and evolved from there. There’s the rub for thinking about atmosphere organisms existing on other planets.

Right, I wont even pretend to be an armchair expert on this just regurgitating what I've read. Long and short of it is we have no idea but from what I recall the original paper was very thorough in trying to explain the phenomenon and life was the most likely hypothesis given what we know. Regardless of the origin it sounds like there is some new science to be found which is exciting.

Venus in the distant past had hospitable surface temperatures.

Oh I did not think about that or know that. That’s true.

“Recent studies from September 2019 concluded that Venus may have had surface water and a habitable condition for around 3 billion years and may have been in this condition until 700 to 750 million years ago.”

It is interesting that this timeline lines up roughly with the appearance of plant and animal life on earth.

And than they've failed to address greenhouse gas pollution.

Do microorganisms spend their entire lives in Earth's atmosphere, or are they simply found there? It doesn't seem surprising that some would find their way up there, but I have a hard time imagining how microorganisms could maintain a certain altitude. On land, they can anchor themselves to hospitable environments to breed, but in the atmosphere, how could they find one another?

Apparently they do live in the upper atmosphere. [1].

> Although many of the organisms borne aloft are likely occasional visitors to the upper troposphere, 17 types of bacteria turned up in every sample. Researchers like environmental microbiologist and co-author Kostas Konstantinidis suspect that these microbes may have evolved to survive for weeks in the sky, perhaps as a way to travel from place to place and spread their genes across the globe. "Not everybody makes it up there," he says. "It's only a few that have something unique about their cells" that allows them survive the trip.

[1]: https://www.sciencemag.org/news/2013/01/microbes-survive-and...

To the best of our understanding, the surface of Venus is isothermal, meaning that there is little variability in temperature, whether on the pole or equator, day or night. That 2016 rash of articles about "cold poles" on Venus were rather misleading interpretations of a single scientific paper about a measurement from the upper atmosphere.

You still have to consider 90 times the air pressure and the acid rains.

That plus the ~500°C at the surface and we have a little paradise to explore

Post author here. I realise I wasn't explicit about the metaphors I was trying to draw.

Mars problems have grand scale but we can see them from the beginning. Google building the original web search index was a Mars problem: massive (at the time) but tractable. Robot cars probably similar: it's an engineering and world mapping problem, and it's tough but we can get there.

Venus problems are knotty, hard to decompose, and characterised by discovering new problems as we go along. UBI is a Venus problem. Vaccines/CRISPR/biology are all Venus problems. Physics is a Venus problem -- notably at the time of the ultraviolet catastrophe which upended everything in the early 20C.

My take is that technology has mainly dealt with Mars problems till now, but now we're facing Venus problems.

It's not quite "title fever", but the point was buried too far in the essay and obscured by the title. HN frequently fails to read, and clearly has here.


Interesting point, worth developing, but a less distracting label and clearer framing, with multiple strongly contrasting examples from different domains might help.

Naturally, nearly all the comments here are about space exploration and not what this article was actually about. I liked the comparison.

I don't think we have dealt with Mars problems at all, the road is still very long for any manned mission and I'm pretty sure the Moon will get its own base long before we even consider the possibility to explore Mars with humans. The base on the Moon being by itself a problem that we have not dealt at all. I mean we started space exploration like yesterday and each new problem seems to go on a logarithmic scale, they are hundred of times harder each time.

I don't follow. Venus is a tractable problem as well. All we need to do is drop a blimp obseravatory on Venus. Its probably even cheaper to do it for Venus than it is to do the same for Mars.

The reason why Mars feels more like a "tractable" problem is simply that we have chased it for decades. Noone gave Venus the attention and funding it could have used to become a tractable problem.

Interestingly, the most friendly environment for us in the Solar system outside of Earth is Venus's upper atmosphere: About 25C, close to 1atm pressure, and 0.9G gravity. It's just like home except for the nasty air.

So, really as long as you have an air-tight membrane made of whatever material resists the atmospheric gases you're good to go. And if you keep a positive pressure then small ruptures of the membrane or leaks are not catastrophic for the occupants, who enjoy comfy conditions and plenty of solar power.

On a slightly related note, what are you favourite science fiction works set largely on Mars or Venus?

I like the Expanse series, but Mars is only a part of those books. I tried to get into Red Mars but I found it a little too dry for me, but I think if you're a fan of "hard sci fi" with realistic ideas of how people would live on Mars it is very interesting!

Red Mars by Kim Stanley Robinson is astounding, the benchmark.

The Space Merchants (Kornbluth/Pohl) is an oddball novel about a hyper-consumerist future, where the settlement of Venus is driven by marketing. It's all about an advertising executive.

Both highly recommended, for different reasons.

As a note, Red Mars is the first volume of a trilogy (there's also Green and Blue Mars). It is quite hard SF with systems that are or were considered as solution for Mars terraformation, very good recommendation !

Total Recall

"Venus, planet of love Was destroyed by global warming Did its people want too much too?" - Mitsky

Don't miss the PBS Space Time episode suggesting we should colonize Venus instead of Mars which gives some good arguments and goes through the basics.

[1] https://www.youtube.com/watch?v=gJ5KV3rzuag

I find it somewhat weird that no one considers gravity when choosing the planet to colonize. Martian gravity is 2.6 times weaker than Earth's and it's the one thing you can't fix. Living with gravity this weak for extended periods of time can't be healthy.

You're a visionary, and I'm so glad reading you rise the gravity issue. When it comes to it, this consideration and the whole extraterrestrial direction-setting exercise, as simple and rational I expect it to go when I speak with others or read their comments, become instead a maturity test I'm waiting for in people willing to take it, and sadly I rarely notice anyone passing it. Another related thought I've had the joy seeing echoed in this discussion thread was the first sentence of this comment: https://news.ycombinator.com/item?id=24574145

Mars is a rock useful for many things, no doubt, but not for humans to live on. As challenging as it seem right now, Venus' problems are solvable, and it just happens to offer the necessary conditions for humans to live on and avoid speciation. If this kind of terrestrial gravity was nowhere to be found but on a planet somewhere as distant as Pluto, we'd still had to go for that (and be thankful for it to exist in our Solar system at all) instead of going for Mars-sized planet and orbit. It just fascinates me that it happens to be the closest us. Humanity will get there and will learn a lot from the process, which is nearly a must-have experience for any further much costlier colonization endeavor on another planetary system.

You can find answers to all your questions in Stapledon’s Last And First Men.

> (“Geo”-logy? I’m not sure what the appropriate word is.)


> Planetology

Unfortunately this has some astronomical ring to it. (I do not think most geologists think of the earth as a planet, to be honest.)

I'm pretty sure they are all educated people and just know that. And it's hard for me to imagine such an unimaginative geologist who wouldn't be able to look at Earth as a planet.

I was wondering about _exogeology?_

What about the recent finding that the atmosphere of Venus seems to contain badger farts?

https://www.nytimes.com/2020/09/14/science/venus-life-clouds... (read with a generous interpretation).

Badgers are known as hardy animals. They also like to dig, which could help with the terraforming.

Why aren't we talking about using badgers to colonize Venus?!? How do we know they haven't beat us to it?

We shouldn't go to Venus because it's like Africa?

I highly recommend to visit Africa. It’s wonderful.

At the very least I'm not going to bless the rains[1] on Venus.

[1] Of hot sulfuric acid

It is not mentioned often but

    distance to Venus = 25,000,000 mi
    distance to Mars = 34,000,000 mi

That’s not really super meaningful in terms of interplanetary travel. For example, for most of the year Mercury is the closest planet to Earth. Change in orbital velocity matters more than distance

For manned travel, travel time matters too.

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