Venus is volcanically alive, new find shows
nationalgeographic.com
nationalgeographic.com
Unlike the earth which has all sorts of tectonics going on and constant interruptions releasing pressure, on Venus the pressure just builds and builds until the crust can't take it anymore and it just pops and you get volcanic activity unlike anything we could probably even imagine.
Then it cools and the pressure starts building yet again.
I am 100% confident that should human society settle on the planet we will totally ignore the fact that's going to happen one day and it will be a amazing catastrophe when it finally does occur.
Might be cooler at the poles.
Or it is 93x atmospheric pressure, which is what 'bar' indicates...
I can also guess what ninety atmospheres entails in terms of engineering, because I know that's the pressure at about 900 m water depth (by virtue of the SI units, which are based off water: P = hρg), which few submarines can even reach.
The same thing goes for 'as long as/as big as xxx football fields': which one? American or association? I know what a square metre is, I know what a square kilometre is, just use the damn units.
I really think pop-sci and science education should emphasise standard units (read: SI, not USC) and being able to estimate orders of magnitude.
Otherwise, it's your reference to submarines that contextualizes the number, same as the insides of a steam engine does for others
I realised that after the fact. What I meant to say is that standard units should be used, and individuals should be left to contextualise said units of their own accord, instead of it being done for them.
The steam pressure is not about the numbers so much but a kind of hyperbole , "you know that thing which hauls tonnes of steel purely on pressure made in a steam boiler , yeah the pressure on Venus is 4 times that pressure "
I found it an interesting fact.
I didn’t think of it that way initially, but this makes sense, thanks.
Oh and I like the unit ‘bar’ because it’s the customary unit for espresso machine pressure (and I’m an espresso nerd with my own machine at home). Espresso machines make espresso by forcing hot water through a puck of finely ground coffee at a pressure between 8 and 12 bar. If you’ve ever worked with an espresso machine, you’ll have an intuitive sense for how much pressure that is (a lot). Venus having 10 times that pressure is also impressive.
Will never happen without major science fiction grade technology, the atmosphere is way too thick to even think about sending anything larger than a tiny probe into.
Sometimes the will just isn't there.
(Gavin Menzies, the author behind the claim China circumnavigated the world before Columbus was born, wrote a third book about how Atlantis did it first. It was equally convincing.)
And I don't see how a colony on Mars even helps with probes. We send material from Earth to Mars and then send probes from Mars? How is that more efficient? Do we even know what materials could theoretically be mined on Mars? And probes are launched with gravitational assists.
Humans are evolved to fit this gravity well. We use the gasses and metabolites here. Trying to leave the planet and make it all work in the dark, cold, bleakness of our solar system is ridiculous. Our lives are fragile and our lifespans too short to make anything offworld viable.
Our robot descendants will inherit the stars instead. There's nothing wrong with human life being just a stepping stone to bootstrap the hand off.
“Trying to leave the savanna and make it all work in the dark, cold, bleakness of Europe is ridiculous.” - some early hominid, fairly recently
We should empower them to go where we can't. In a sense they'll be our children, carrying the torch and memories of humanity with them.
Like if they have a society, maybe their founding myths will involve a baby robot created by some (non-human) robot deity, or if they are more rational a pseudo-scientific story of evolution from a toaster.
And once we had done that, we couldn't go back in significant numbers before inventing sun cream to functionally replace the melanin our bodies no longer produced in enough quantities to prevent our skin burning and developing cancer just from being in the sun.
Technological progress may make this all faster than evolution, but a mechanism that's optimised for Venus may freeze solid on the hottest day in Death Valley, Earth.
Ask yourself why. What's the real job to be done by humans on Mars? What's the real economic situation? How does it map to human desires?
Robots will do the job even better than us and will see 10,000x the investment. Evolution follows gradients of least resistance.
Human history offers plenty of precedent for this; "we want to run things our own way", "all the land is taken where we live", etc. I don't wanna live in Scottsdale, AZ either, but someone does.
(And I'm saying that as an optimist because I want the billionaires to develop that tech: the ability to fully terraform Mars into a self-sustained world is necessarily also sufficient to handle any imaginable damage to Earth up to and including a surprise impact with a moon-sized rock that excavates the crust and mantle everywhere to a depth of a few thousand km, meaning that things like greenhouse gases and biodiversity would become as easy to fix in that future as a single broken window is today; even just the bare minimum of a single self-sustained domed city on Mars means most environmental issues have to be "solved").
Nevertheless, I think "my skin burned and blistered" is a bit more immediate with the painful feedback, even if it's not as extreme.
Nobody is going to want to live through either those days or those nights
The only thing venus has, that makes it interesting for human settlements, is earthlike gravity - but the rest is pretty hell like.
The Earth weighs more than everything else between the sun and Jupiter combined, and Venus is 80% of that.
But yes, I also see no way of "fixing" the g of mars(which is likely way too low for humans), unless we go into the buisness of planet building.
We don't really have a way to know until we get experimental data (real humans on Mars). Until then, it's all just (un)educated guesses.
We know that long time weightlessness causes damage, so 38% of earths gravity will likely have some bad effect, too. This is not just wildly speculating. But yes, for finding out, whether humans still can bear it, we will have to find out and there is no shortage of volunteers.
First you want to get your self-replicating probes occupying the Oort cloud, whatever. Get ready to sort and aim. You start with your "rocky" bodies, skipping them off of Venus' atmosphere, just ripping it off in big hunks, until you're down to about one Earth atmosphere.
Next, you flat up drop your icy bodies into Venus, because it really needs water.
During that time you'll want to start constructing your insolation shield, to help cool things down.
Only after that can you move Mercury into place.
The outgassing CO2 could be captured and turned into carbon and oxygen, with the carbon put to industrial use or into biomass and the oxygen feeding a 400 millibar O2 atmosphere in settlements.
But a sudden volcanic triggered burst of CO2 would be a forever ongoing global risk.
The Soviet Union did send probes to Venus back in the 70s. But, indeed, it would be great to have new and higher resolution photos. I am always amazed when looking on the surface of a foreign world.
EDIT: oh and there is oxygen everywhere, if your spacecraft doesn't corrode it will burn. And even if it lands 2/3 of this planet are covered with 4km deep oceans of the corrosive stuff!
What do you mean?
Venus has already received its fair share of probes, the Venera missions, some weighted upwards of five tons
https://en.wikipedia.org/wiki/Venera
They did many different types of measurements, and lasted from one to two hours before their batteries running out, some atmospheric probes lasted days
I think we should be aggressively seeding its atmosphere with extremophiles, hoping that something evolves to transform all that free energy into life.
https://www.humans2venus.org/why-venus
Would people floating 50 km up be able to just ignore that sort of vulkanism? I have no idea but I hope some science fiction author investigates and writes a story on the topic.
Moreover, if we are to consider possibilities beyond our current capabilities, why not focus on building space stations with artificial gravity instead? There would be no need to be tethered to Venus when we could exist without any attachment (although we would still be subject to gravity of other entities).
Note that at sufficient height over Venus, air is buoyant, so quite a few designs for Venus assumes at least part of the habitation itself is within the structure of the blimps, and the pressure means leaks are much more manageable. You also get a "free" radiation shield on Venus thanks to the induced magnetic field, and that alone might well be enough to make it more attractive than a larger space station.
We don't know if a full Earth gravity is necessary for human health in the long term, or if we could get away with something less, like half a gee. And we don't know how small the centrifugal force gradient has to be between the feet and the head for people to be comfortable. It might turn out that we could just get used to it, like how people get over space-sickness, so a spinhab with a relatively small radius might be fine. All we know for sure is that prolonged exposure to zero gravity causes a gradual decay in bone and muscular strength.
There was a plan for the ISS to have a spinning module to study these questions but it never happened. It's a shame, that kind of experiment would be far more valuable than whatever public relations crap they're doing up there. I actually find it astounding that we haven't even tested long term partial-gravity on animals yet.
https://hackaday.com/2021/06/08/iss-artificial-gravity-study...
The main point against is that there is no reason for anyone to go there. Cloudtops on Venus are immensely resource-poor, most importantly in hydrogen. I agree with you that there is no advantage to a floating colony over a spinning one.
The one place on the solar system whose colonization is often ignored is Mercury. It has an extremely low axial tilt, meaning that all the craters on it's poles are permanently shadowed. It is also constantly bombarded by solar wind, which produces water (ionized hydrogen impacts oxide rocks, and binds to the oxygen). Then the water is a gas that bounces around until it impacts the bottom of a shadowed crater, which is cold enough to freeze it. Based on data from the MESSENGER mission, the south pole of Mercury alone has more water than all of Mars.
That's not really a point in favour compared to an orbiting spinhab. You only need it to float so that it doesn't fall to the ground. And you can achieve that by not leaving orbit in the first place.
A floating habitat would have less access to orbit, would have density / weight contraints and would have to deal with the corrosivity of the venusian clouds.
Those are very different engineering challenges. Separating similar pressure gas mixtures is question of porosity, but not force. Separating different pressures of the same gas mixture is not just a question of porosity, but you also need manage the forces created by the overall pressure differential.
Edit: If you take a helium balloon into space (or high enough in our atmosphere) it explodes rather than just slowly leaking and equalizing it's gas mixture with the atmosphere.
That will come in handy when we deconstruct Mercury to provide the raw materials for a Dyson swarm.
So, AIUI, it's easier to get to Alpha Centauri than to "fall into" the star we orbit.
It would actually be easier than on Earth because on Venus atmospheric pressure increases like crazy as you get near the surface. So an habitat pressurized at 1 Earth atmosphere would naturally float in Venus' atmosphere like a submarine or whatnot floats in Earth's oceans.
My understanding is that at the relevant altitude in Venus' atmosphere the temperature would also be very Earth-like so no big heating/cooling issues, either. I have read some say that the upper atmosphere of Venus is actually the most human-friendly environment in the solar system outside of Earth.
It's actually not a far-fetched proposal.
But of course at the right height breathable air is also buoyant on Venus, and that's one of the key things that makes floating habitats attractive - we can use air for lift and live inside the balloons, and thanks to the equivalence of pressure small leaks shouldn't be an issue. Multiple compartments plus some spare, un-inflated sections, and you can have decent redundancy.
(I am planning a book set in part on Venus, but it's book 6 of a 6 book cycle and I'm currently being very slow about finishing book 3)
Plus makes emergency procedures for leaks MUCH cheaper - light emergency ponchos and masks, and just walk over to the next sealed building.
I'm assuming you mean sealed buildings inside the blimps here, because you'd have nowhere to walk to on the outside on account of being 50km above ground. In which case you probably wouldn't need anything in the case of a leak.
I am 100% confident that should human society settle on the planet we will totally ignore the fact that's going to happen one day and it will be a amazing catastrophe when it finally does occur.
How 'one day' is that one day volcanic event on Venus compared to one of the extinction events Earth has had?
The whole planet exploding, however? Lava flowing across the whole planet at the same time? Hilariously catastrophic.
1 - https://www.goodreads.com/series/112296-the-broken-earth
The relevant question from the GP was, how long ago was the last time this happened on Venus? Because we've got something similar here around 60 million years ago.
does the fact that Venus has no moon play into the lack of tectonics?
_On_ Venus? That seems unlikely; if anything it'd be _above_ Venus (there's a not-that-absurd argument that sections of Venus's atmosphere are far more hospitable than, say, Mars, and of course this tickles sci-fi writers' love of big airships, so it comes up a lot in fiction).
(Though I assume that even then, the whole surface exploding would be undesirable.)
If we allow for pretty long timescales, we are pretty much doing that with Yellowstone here on Earth.
https://archive.org/details/BBCHorizonCollection512Episodes/...
If you watch it you'll hear the story of Venus plate tectonics and they present it in such a way as to make it one of the most fascinating mysteries of the solar system.
It's a documentary worth settling in to for an hour on the couch and enjoying the ride.
Anyhow my theory (as a highly qualified astro geologist) is that Venus, whilst being the same size as the Earth does not have plate tectonics because it does not have a moon which pulls the magma around the planet, stirring it up nicely. Instead, Venus surface just cools off and then gets hot again periodically. I hope you didn't buy the astro geologist line.
Astronomers may have found a signature of life on Venus
Evidence indicates phosphine, a gas associated with living organisms, is present in the habitable region of Venus’ atmosphere.
In particular:
MIT scientists have previously shown that if this stinky, poisonous gas were ever detected on a rocky, terrestrial planet, it could only be produced by a living organism there.
Something to do with the amounts being minuscule, the fact that there are valid explanations outside of biology that could create such a chemical.
just always annoyed me that someone was paid to pretend like one of our great telescopes saw something that looked like what the headline says
Parker Solar probe I believe made a few passes in the last couple years that added some terrain mapping and a few headlines about life possibilities based on some spectrographic reads that ended up being debunked. But I dont think much else has been done.
All that is to say, something from 30 years ago is probably still pretty relevant for Venus.
If moonless Venus also has volcanic activity, then clearly our moon is not necessary for that. But if Earth has tectonic activity while Venus doesn't, then why that difference? I would have expected tectonic and volcanic activity to go hand in had, but clearly that's not necessarily the case.
The presence of water at many fault lines is essential to allowing plates to stay separate and move relative to each other. The subduction and divergence is then essential to gas exchange between atmosphere and mantle that gives the system stabilizing inertia.
It's unclear what came first on Venus, but it's pretty clear that high temperature, boiling water (a greenhouse gas!), and stagnant lid tectonics all provided positive feedback to each other, with the boiling off of water probably kicking the process into high gear.
Having at least some faults that slippery is necessary to keep the system from locking up.
There's an explainer here: <https://www.nps.gov/subjects/geology/plate-tectonics-subduct...>
As to the role in tectonics and plate movement, I'm less aware.
Reminds me of the Vajont Dam disaster, in which filling of a reservoir behind a newly constructed dam lead to catastrophic collapse of a mountainside in the Italian Alps, where layered sedimentary limestone separated by thin layers of clay became unstable as the clay was wetted and lubricated by the reservoir.
Shortly before 11 pm on 9 October 1963, a two-kilometer-long landslide triggered a 250m (850 ft) megatsunami. That killed a number of engineers who'd gathered on top of the dam to observe its filling, as well as around 2,000 inhabitants of villages adjacent to and downstream of the reservoir, most notably Longarone which was virtually scrubbed from the map.
The dam itself was virtually undamaged by the incident, save the topmost metre or so of nonstructural masonry.
Tidal forces are likely a factor in plate tectonics, though sources I'm familiar with suggest that virtually all the energy is contributed, roughly equally, by latent heat of gravitational formation (that is, the kinetic energy of source material colliding) and radioactive decay. What I've seen in estimates of tidal energy as a renewable source are that it is vastly smaller than even geothermal generally, as well as unconcentrated (natural geothermal vents, volcanoes, geysers, etc., provide zones in which significant direct energy capture is possible upwards of 1 GW in a single zone, as with the California Geysers geothermal generation project).
Tides are absolutely a factor in ocean cycles (and early in the Moon's lifespan would have been cataclysmic as the Moon orbited far closer to the Earth). Lunar cycles are evident in life-forms everywhere (the shell of the nautilus, for example, records the duration of the month throughout geological time, covered in Daniel Botkin's The Moon in the Nautilus Shell <https://www.danielbbotkin.com/books/the-moon-in-the-nautilus...>). Cycles of moonlight and darkness drive many animal behaviours. The giant-impactor hypothesis of lunar formation would have had a profound effect in the distribution of elements and minerals within the Earth's crust. And that's just off the top of my head as a non-specialist.
and the youtube example: https://www.youtube.com/watch?v=bJ_seXo-Enc
The hard part is "in space", where we need to solve both ISRU and getting there cheaply[0] for this to be anything other than vanity projects.
[0] Starship, if it works as advertised, is a wagon train to the stars — you need it to get going, but you don't want to do the Oregon trail in a wagon train when you have an airline or an interstate highway at your disposal.
Keyword: Coriolis (pseudo)force
Its importance goes down when the parent object gets bigger compared to the contained object, which is why it's not important to draining but is important to hurricanes.
Spinning orbital structures have to basically hang from themselves and deal with primarily tension forces rather than compression forces.
Now, I know you're going to say "not airtight", and that's correct, I'll get to that:
https://en.wikipedia.org/wiki/London_Eye
Also very nearly that scale 130 years ago:
https://en.wikipedia.org/wiki/Ferris_Wheel_(1893)
Making ferris wheels airtight is somewhat pointless, but would be in certain regards easier in freefall than on the ground as (a) it doesn't need to start off spinning and therefore doesn't need to be stable until it's finished, and (b) there's not going to be the same concerns about metal fatigue because the force isn't going to constantly change direction from the reference frame of any given element.
If that can be balanced against (c) we've barely scratched the surface of space manufacturing and don't know what to expect, remains to be seen.
There is no question that building a rotating structure with that kind of mass at that kind of scale rotating at those kinds of speeds is going to create significant novel engineering problems.
Those problems become even bigger when you consider that this structure has to be built in space (we've never built anything of this size in space, let alone tried to spin it up) and you have to solve problems like thermal expansion/contraction that will only get harder with scale.
You're being too literal, "stadium" isn't an SI unit and 120 metres is bigger than the 112 meters suggested in the article up-thread, so the technicality is not an important point.
Also, the core point is that the tensile strength required is nothing special. Indeed this is why the O'Neill designs are the size they are (8x32 km) and you only need to jump to mass-produced carbon nanotubes for the much larger and more ridiculous McKendree cylinder (size: Russia).
> kinds of speeds is going to create significant novel engineering problems
No doubt, novel things usually do even on the ground, that's why civil engineering is the discipline that it is — but can you name any not already faced by, say, suspension bridges?
In particular: what is speed supposed to do in this case, given its in space, and chosen specifically for 1g acceleration like everything on Earth is anyway?
I'm not sure how useful these would really be, of course. Only way to tell is to wait and see, unless you're working for Bezos or Musk and they're paying you to actually do the thing.
(Heck, part of me thinks they could be so terrible in practice that they are one of the fillers in the Fermi paradox, but I really should tidy up those thoughts into a proper blog post rather than ramble in a comment…)
Well, yes, that's probably enough for a people-container, where a few people can get a small room and a zero-g workplace on the middle.
It doesn't afford any comfort (so, more than some 6-months long journeys are a problem), but I can indeed imagine that being useful.
Though without specific use-cases to ask questions about — and I have none — you're right by default: just because it's possible, doesn't make it good for anything specific.
It would be better to place the rotating cities inside Ceres or other asteroid, so you don't need to build thick walls to stop radiation and meteorites.
Also you are already in a body you can mine and has a small gravity to build farms. Ceres is a good place to have a midway station to send ships further out the solar system. But another nice location would be an asteroid with an elliptic orbit and perihellion near Earth, aphelion near Ceres, that could act as a shuttle.
Also, his 1977 short La Soufrière[1] is set on an island where a volcano is about to erupt.
[0] https://www.imdb.com/title/tt9203832/
[1] https://www.imdb.com/title/tt0076741/
Link to Into the Inferno: https://www.imdb.com/title/tt4846318/