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Venus' Crust Heals Too Fast For Plate Tectonics

samzenpus posted about 5 months ago | from the too-hot-to-crack dept.

Earth 135

An anonymous reader writes in with an interesting look at how important plate tectonics may be to life and why the crust on Venus works differently than it does on Earth. "Without plate tectonics, carbon would build up in the atmosphere. Venus, which does not have tectonics, shows the results: an atmosphere that is 96 percent carbon dioxide. It's toxic. Yet Venus is about the same size and composition as our planet, so why doesn't it have plate tectonics? Some researchers made a model to explore how Earth initiated plate movements, and these same researchers made one model of its neighbor for comparison. A 1.5-billion-year-old Earth and a similarly aged Venus were modeled as a hot, mushy material made of tiny particles of rock. The model uses physics at the one-millimeter rock grain scale to explain how the whole planet behaves. According to David Bercovici, a geophysicist at Yale who was an author on the paper, the model also shows how plate tectonics emerged on Earth but not on her twin."

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Venus isn't Earth's "twin" really at all. (1, Insightful)

Anonymous Coward | about 5 months ago | (#46806171)

Is it very surprising that a completely different orbit around the sun and different composition result in different crust phenomena?

Re:Venus isn't Earth's "twin" really at all. (1)

Anonymous Coward | about 5 months ago | (#46806331)

Is it very surprising that a completely different orbit around the sun and different composition result in different crust phenomena?

No, but that's not what the article is about either. The article is saying that they've found a causal mechanism linking the known differences in venus's orbit/formation to the observed lack of tectonic plates. And more importantly they have a model that may allow them to predict what planets would/would not have tectonic plates based on their temperature.

Re:Venus isn't Earth's "twin" really at all. (2)

rubycodez (864176) | about 5 months ago | (#46806363)

you are mistaken, the composition of Venus rock from surface on down is nearly identical to Earth.

Re:Venus isn't Earth's "twin" really at all. (3, Insightful)

darthlurker (663459) | about 5 months ago | (#46806445)

There's a big difference between Earth and Venus.

Later doesn't have an over-sized moon.

Re:Venus isn't Earth's "twin" really at all. (1)

mmell (832646) | about 5 months ago | (#46806695)

Currently theorized to have resulted from an impact so severe that it nearly shattered the planet, an impact so severe that the entire surface of the planet was blasted loose and redeposited on the surface.

Re:Venus isn't Earth's "twin" really at all. (1)

NatasRevol (731260) | about 5 months ago | (#46806983)

blasted loose, cooled, and redeposited on the surface.

Hmmm. that might make some nice big rocky plates.

Re:Venus isn't Earth's "twin" really at all. (1)

VernonNemitz (581327) | about 5 months ago | (#46809073)

I think the authors of the paper have overlooked something. It has been discovered that if we pump water into the ground along a fault line, we can literally lubricate the fault and help the plates slide past each other. (Side note: sounds like a good way to prevent major earthquakes, but nobody wants to be responsible for causing the initial quakes associated with unlocking long-locked plates. The problem with that attitude is, those quakes are eventually going to happen anyway, except they will be bigger and more catastrophic then, than if deliberately caused now.)

Anyway, on Earth we have lots of water, including water deep underground, presumably doing SOME assisting of tectonic plate motion. Meanwhile, on Venus it has always been too hot for much water to percolate deep underground....

Re:Venus isn't Earth's "twin" really at all. (0)

Anonymous Coward | about 5 months ago | (#46809745)

I think the authors of the paper have overlooked something. It has been discovered that if we pump water into the ground along a fault line, we can literally lubricate the fault and help the plates slide past each other. (Side note: sounds like a good way to prevent major earthquakes, but nobody wants to be responsible for causing the initial quakes associated with unlocking long-locked plates. The problem with that attitude is, those quakes are eventually going to happen anyway, except they will be bigger and more catastrophic then, than if deliberately caused now.)

Next your going say something crazy like the steam generated by lubricating these tectonics could be used to generate power of the electrical kind. Some fantasy world you live in.

Re:Venus isn't Earth's "twin" really at all. (2)

FatdogHaiku (978357) | about 5 months ago | (#46810231)

There's a big difference between Earth and Venus.

Later doesn't have an over-sized moon.

That adds a lot of stress. Then pile on 1.3 billion cubic kilometres of water that tends to try to follow the moon around...
1,400,000,000,000,000,000 metric tons sloshing around would put cracks in pretty much anything.

Re:Venus isn't Earth's "twin" really at all. (2)

Will.Woodhull (1038600) | about 5 months ago | (#46810297)

Is it surprising that there is a difference in the behavioral history of a single planet and a similar planet that happens to be part of a binary planet system?

Hint: Venus does not have tides; has never had tides. Earth tides were a lot larger when Earth was young and the Moon was closer. They are still large enough to put a significant do-si-do waggle in the Earth's orbit about the Sun. Despite what dumb-ass astronomer conventions might say, when a satellite is so large that it deflects its primary from its orbit by 4,000 miles, you have a binary planet.

Why do so many Earth "scientists" fail to see that you cannot talk sensibly about Earth's mechanics without acknowledging the Moon's influence? Of course there is going to be a difference between the pot that sits on the stove undisturbed, and the one that is constantly stirred.

</rant>

Re:Venus isn't Earth's "twin" really at all. (1)

able1234au (995975) | about 5 months ago | (#46810819)

which "dumb-ass" scientists that do not influence the impact of the moon on the earth are you talking about?

The Moon is considered a moon as the barycentre is within the Earth. Pluto on the other hand has its barycentre outside of it, though in its case we usually refer to it as a Dwarf planet rather than Dward binary. ...or am i missing something?

Re:Venus isn't Earth's "twin" really at all. (2)

Will.Woodhull (1038600) | about 5 months ago | (#46811773)

No, you have not missed anything. You are parroting the "logic" of the Committee for Small Body Nomenclature of the International Astronomical Union. This is a true committee of fifteen members whose job it has been to decide on definitions of words. There was and is no science here. Nor was there any logic based on science; the logic was that of taxonomy: making pigeonholes to classify stuff. Nor was logic used in making the final determinations; what the pigeonholes were to be called was decided by vote. It was a "let's make new words" party, having nothing to do with astronomy, geology, or selenology. (See? It is both easy and fun to add words to the pseudoscientific jargon. Even scientists can do it!)

The Moon is considered a moon as the barycentre is within the Earth.

The barycenter of the Earth-Moon binary system (and that is a legitimate phrase) is always 1,000 miles below the lithosphere of the Earth, and 3,000 miles above the Earth's core. Quito, Equador, is a city on the equator. When there is a lunar eclipse on either the Spring or Autumn equinox at Quito, an interplanetary voyager arriving from Mars would find that Quito was 1,500 miles closer to the Sun than usual, but 12 hours earlier or later it was almost 1,500 miles further from the Sun than the navigator's first order approximation*. The communications officer of that interplanerary ship had better take into account the way the Earth spins about the barycenter of the binary system if he is to stay in laser beam contact with the Quito space port.

More significantly over the Earth's history is that its rotation around the barycenter raises tides. Not just the noticeable ones in the hydrophere, but large ones in the various layers of the atmosphere, and smaller, but significant, ones in the lithosphere. Geology has yet to develop an effective model on how the tidal strains on the lithosphere affect plate tectonics. But there can be little question that significant tidal forces are at work, alternately stretching and compressing faults.

In retrospect, what this august body of astronomers should probably have done is given their naming problem over to the experts who have recognized degrees in the appropriate field of study: these kinds of taxonomic decisions are better left to the linguists and other language experts. There are probably very few astronomers who have done any study of language arts at all. No wonder they bungled the thing so badly. They probably did not even know they were not doing astronomy any more. *

I would not mind having someone check my geometry here. I think the difference is actually 3,000 miles (displacement of the Earth's center from the barycenter) but I'm going with the more conservative number.

Re:Venus isn't Earth's "twin" really at all. (1)

able1234au (995975) | about 5 months ago | (#46811991)

Well you do need a naming system and Planet is a useful naming system. What is evil about that? There are only 8 planets so you don't really need to subdivide them more. And if the earth-moon is a binary then what are Mars, Jupiter, Saturn, Uranus and Neptune? Pluto on the hand was relabelled by that evil committee not because it is also a binary, quaternary or whatever, simply because there are potentially thousands of dwarf planets, so calling them planets was not useful. That is usually the big complaint about that committee. I hadn't heard that people were unhappy about the Moon's status.

Re:Venus isn't Earth's "twin" really at all. (0)

Anonymous Coward | about 5 months ago | (#46811877)

Venus has tides from the Sun. For comparison, Earth's tidal acceleration at its surface from the Moon is a little over twice that of the tidal acceleration caused by the Sun. The tidal acceleration caused by the Sun on Venus is three times that of the solar tides on Earth, giving a larger stress on Venus than Earth gets from the moon. The only big difference is that the rotation of Venus is a lot slower.

Re:Venus isn't Earth's "twin" really at all. (0)

Anonymous Coward | about 5 months ago | (#46812305)

Well, to start with, Earth is from Mars. And Venus is from Venus, you insensitive clod!

Carbon dioxide is *NOT* toxic. (0)

Anonymous Coward | about 5 months ago | (#46806179)

Hundreds of millions of plants would challenge the notion that carbon dioxide is toxic.

Re:Carbon dioxide is *NOT* toxic. (1)

Anonymous Coward | about 5 months ago | (#46806267)

It tends to get a bit inhospitable when it's at a temperature of 737K and about 9.2 MPa of pressure (92 times what we have here), though...

Re:Carbon dioxide is *NOT* toxic. (1)

arfonrg (81735) | about 5 months ago | (#46806385)

Wait, so it's NOT the lack of tectonics that prevents life on Venus but this "737K @ 9.2MPa" thing?

Re:Carbon dioxide is *NOT* toxic. (1)

mmell (832646) | about 5 months ago | (#46806705)

Well, yes - but that

"737K @ 9.2MPa" thing?

might theoretically have been caused by the lack of plate tectonics.

Re:Carbon dioxide is *NOT* toxic. (0)

Anonymous Coward | about 5 months ago | (#46806991)

Well, yes - but that

"737K @ 9.2MPa" thing?

might theoretically have been caused by the lack of plate tectonics.

RTFA.

The starting point was the heat on Venus. That's what made the Venusian crust softer, thus preventing the creation of tectonic plates.

Re:Carbon dioxide is *NOT* toxic. (1)

mmell (832646) | about 5 months ago | (#46807095)

Badly worded on my part.

I was trying to express the idea that being closer to the Sun might not be the only factor involved. I personally suspect that it's the primary cause (and might be enough even if all other conditions were identical on Earth and Venus), but TFA is only positing a theory that there are other factors contributing to the differences we see.

Re:Carbon dioxide is *NOT* toxic. (0)

Anonymous Coward | about 5 months ago | (#46807907)

The real question is why venus has such a thick atmosphere. If you compare the temperature at the same pressures as earth troposphere it is nearly exactly as would be predicted due to being closer to the sun. Isn't mars supposed to have lost its atmosphere due to lack of a magnetic field? But venus also has no magnetic field and has a much thicker atmosphere.

Good question. (1)

mmell (832646) | about 5 months ago | (#46808279)

I'd always thought it might have something to do with lower planetary mass and surface gravity. Works for Mars, but Venus is also smaller than Earth - and close enough to the Sun that solar wind should be stripping the atmosphere off into space.

IANARS.

Re:Good question. (0)

Anonymous Coward | about 5 months ago | (#46808633)

I searched around a bit. The answers seem to go something like this:

Venus has a strong ionosphere that protects it against violent solar winds. So, even though Venus has no intrisic magnetic field, it has an effective, induced magnetic field due to the interaction between the solar winds and the atmosphere, that protects it against solar winds.

Venus atmosphere is thick enough to have a consequent ionosphere, that would be the difference between Mars and Venus (and Venus was able to keep a thicker atmosphere due to its greater mass, contrary to Mars).

https://astronomy.stackexchange.com/questions/639/why-has-venuss-atmosphere-not-been-stripped-away-by-solar-wind

The chain of causality of this argument is fuzzy to me. "Venus has an induced magnetic field because of its thick atmosphere, the thick atmosphere is possible due to the induced magnetic field". It is like the chicken/egg problem.

The primary argument seems to be that venus' higher mass allowed it to retain a denser atmosphere originally, but this is always presented as an aside rather than the root cause for some reason.

Re:Good question. (0)

Anonymous Coward | about 5 months ago | (#46808787)

Same AC. Actually that argument still doesn't really explain anything because Earth is larger than Venus, has both types of magnetic fields, but has a much thinner atmosphere.

Re:Good question. (1)

mmell (832646) | about 5 months ago | (#46808871)

I'm guessing "IDGI" is not a good answer. :)

Re:Good question. (0)

Anonymous Coward | about 5 months ago | (#46809205)

The controversy stems from recent observations that show Mars and Venus are losing oxygen ions from their atmospheres into space at about the same rate as Earth. This came as something of a surprise, since only Earth has a strong dipolar magnetic field that can prevent solar wind particles from slamming into the upper atmosphere and directly stripping away ions.

My opinion is that the magnetic shield hypothesis is unproven," said Robert Strangeway from UCLA. "There's nothing in the contemporary data to warrant invoking magnetic fields."

http://www.space.com/11187-earth-magnetic-field-solar-wind.html

So apparently no one knows why venus is so hot.

Re:Carbon dioxide is *NOT* toxic. (1)

LifesABeach (234436) | about 5 months ago | (#46808017)

Are there mountains on Venus?

Re:Carbon dioxide is *NOT* toxic. (1)

mmell (832646) | about 5 months ago | (#46808127)

Mountains and volcanos. Venus most certainly is subject to geologic forces; but current theories and observations do not indicate the presence of geologic plates - therefore, no plate tectonics. Venus' crust appears to be a single, contiguous solid whole, not the fractured group of mechanically separate massive plates found here in Earth.

Re:Carbon dioxide is *NOT* toxic. (1)

arth1 (260657) | about 5 months ago | (#46808357)

Are there mountains on Venus?

Through first hand experience, I can verify the abundance of Venus Mons.

Re:Carbon dioxide is *NOT* toxic. (3, Insightful)

LordLimecat (1103839) | about 5 months ago | (#46806343)

Amanita phalloides (Deathcap mushrooms) are NOT toxic.

Hundreds of thousands of rabbits would challenge the notion that it is toxic.

Re:Carbon dioxide is *NOT* toxic. (1)

Eunuchswear (210685) | about 5 months ago | (#46806369)

Are you a plant?

Re:Carbon dioxide is *NOT* toxic. [Zepped!] (3, Funny)

Tablizer (95088) | about 5 months ago | (#46806395)

Are you a plant?

Yes, but call me Robert.

Re:Carbon dioxide is *NOT* toxic. [Zepped!] (1)

Eunuchswear (210685) | about 5 months ago | (#46810885)

Bob is that you?

Why are you so angry?

Re:Carbon dioxide is *NOT* toxic. (0)

Anonymous Coward | about 5 months ago | (#46806387)

Um, are you stupid, very stupid, extremely stupid or full-on inbred retarded? Oxygen isn't toxic either I guess, except at 100% concentrations... Idiot.

Re:Carbon dioxide is *NOT* toxic. (2, Insightful)

Anonymous Coward | about 5 months ago | (#46806481)

At sufficiently low doses, nothing is toxic. At sufficiently high doses, everything is toxic.

Did you know you can (and people do every year) die from water toxicity?

Re:Carbon dioxide is *NOT* toxic. (0)

Anonymous Coward | about 5 months ago | (#46809729)

As the proverb goes, it's the dosage that does the damage.

Rare Earth? (4, Informative)

K. S. Kyosuke (729550) | about 5 months ago | (#46806209)

I believe I've read similar arguments some time ago in a book titled Rare Earth: Why Complex Life is Uncommon in the Universe [amazon.com] . It was published a decade ago. So it's a slow news day again, I guess. ;-)

Re:Rare Earth? (1)

K. S. Kyosuke (729550) | about 5 months ago | (#46806275)

(Just to be a little bit more specific, this was about the "how important plate tectonics may be to life" part, not about new findings in the area of plate tectonics mechanisms which I'm sure are new.)

Re:Rare Earth? (1)

radtea (464814) | about 5 months ago | (#46807323)

You added your own addendum, but it's worth repeating: the idea that plate tectonics is important to life is not new.

The detailed model as to how and why plate tectonics got going on Earth and that also explains why it didn't get going on Venus is both new and interesting, which is pretty much the definition of "news for nerds, stuff that matters", eh?

Re:Rare Earth? (1)

K. S. Kyosuke (729550) | about 5 months ago | (#46807493)

It's the editing of the submission that I find (mis)leading.

Re:Rare Earth? (1)

Tablizer (95088) | about 5 months ago | (#46807695)

But we don't know if Earth's path to complex life is the only viable path. There may be "other angles" to get to complex life. We only have one sample to judge on.

Why? (1)

StripedCow (776465) | about 5 months ago | (#46806215)

Without plate tectonics, carbon would build up in the atmosphere

Why is that?

Re:Why? (0)

Anonymous Coward | about 5 months ago | (#46806271)

How much limestone do you think is on earth?

Re:Why? (0)

Anonymous Coward | about 5 months ago | (#46806429)

Not a whole lot, really. It's a fucking huge planet.

Re:Why? (5, Informative)

K. S. Kyosuke (729550) | about 5 months ago | (#46806349)

If you bothered to read the article (or the book I linked), you'd find out that plate tectonics is crucial in the long-term carbon cycle that snatches carbon-containing minerals and, passing through subduction zones, deposits them in the depths of the Earth. (I'm not a geologist but I also vaguely recall that the hydration of these minerals contributes to the increased levels volcanic activity near the subduction zones, by means of lowering the melting point of rocks - which is how the cycle gets closed, since this volcanic activity releases the carbon back.)

Re:Why? (1)

tomhath (637240) | about 5 months ago | (#46806505)

which is how the cycle gets closed, since this volcanic activity releases the carbon back

That's kind of the question though. A huge amount of carbon is tied up in the Earth's crust. Some gets pulled down into the mantle, some gets released. From what I've read that cycle is in balance. So why wouldn't the carbon in the limestone stay there without tectonics?

Re:Why? (1)

K. S. Kyosuke (729550) | about 5 months ago | (#46806711)

I'm not sure it's about the limestone "not staying there", I always understood it as a matter of increasing the crust's overall absorbing capability, by circulating it over greater thickness of rock layers. If you absorb as much CO2 in a comparatively thin (but static) layer of rocks near the surface as you can (with the absorption speed steadily decreasing), what happens then to the rest of atmospheric CO2? That might just be the thing that happened to Venus. Or not. I'm not the expert, I'm afraid.

Re:Why? (0)

BitZtream (692029) | about 5 months ago | (#46807173)

So basically you're just making shit up as you go? Somehow you think that the crust wouldn't be layered without plate tectonics even though that isn't the reason the crust is layered in the first place ...

In that situation, when you can just make up silly answers to the holes in your theory, any theory can look sound.

Re:Why? (1)

K. S. Kyosuke (729550) | about 5 months ago | (#46807275)

If by "making shit up as I go", you mean "recalling interesting stuff from books I've read years ago", then yes. Otherwise you're not making too much sense.

Re:Why? (0)

Anonymous Coward | about 5 months ago | (#46807413)

So why wouldn't the carbon in the limestone stay there without tectonics?

Because no tectonics does not mean no volcanoes.

Re:Why? (0)

Anonymous Coward | about 5 months ago | (#46806441)

Volcanos release carbon in the atmosphere. This carbon can be fixated in carbonate rocks or in organic carbon (mainly in carbonate rocks), but only up to a point. Plate tectonics provide a good way of putting carbon back in the mantle by subduction (sinking plates in the deep Earth).
 

The geology department is trying to... (0, Insightful)

Anonymous Coward | about 5 months ago | (#46806223)

The geology department is trying to justify themselves again - "Some scientists think that plate tectonics are essential for life". What a load of crap!

What a dumb article, the dirt monkeys make this supposition: "Venus doesn't have life because there are no tectonics (we think)". Maybe it doesn't have life because it's being scorched by a nuclear furnace????

Re:The geology department is trying to... (0)

oodaloop (1229816) | about 5 months ago | (#46806281)

Maybe it doesn't have life because it's being scorched by a nuclear furnace????

Whew! Good thing Earth isn't being heated by a giant thermo-nuclear oven too!

Re:The geology department is trying to... (0)

Anonymous Coward | about 5 months ago | (#46806355)

"Heated" and "Scorched" are two different things... Thank you for playing, come again.

Re:The geology department is trying to... (1)

Eunuchswear (210685) | about 5 months ago | (#46806421)

Venus gets about twice the insolation that the Earth gets, not an amazingly large amount more.

Re:The geology department is trying to... (1)

Tablizer (95088) | about 5 months ago | (#46806365)

but we are being "lightly toasted", not "scorched"; that's the difference. (Time to use cooking terms, for libraries-of-congress analogies are getting old.)

geos' theory half-baked (2)

Thud457 (234763) | about 5 months ago | (#46806549)

ob. The Far Side [sonoma.edu] reference

Re:The geology department is trying to... (4, Insightful)

CrimsonAvenger (580665) | about 5 months ago | (#46806403)

Maybe it doesn't have life because it's being scorched by a nuclear furnace????

Whew! Good thing Earth isn't being heated by a giant thermo-nuclear oven too!

Venus gets about twice the solar irradiation we do here. If we got 2.5kw or so per square meter here, this planet would be uninhabitable too.

And since the Great Oxygen Event had a biological cause, it's probable we'd have a CO2 atmosphere too, with or without plate tectonics, if we had Venus levels of solar irradiation.

Re:The geology department is trying to... (1)

Anonymous Coward | about 5 months ago | (#46807543)

Insolation isn't the issue. Mercury gets around 3.5 times that of Venus, but is cooler.

Venus' temperature is largely due to an extreme case of the greenhouse effect, arising from a dense, CO2-rich atmosphere.

Re:The geology department is trying to... (3, Informative)

dryeo (100693) | about 5 months ago | (#46808859)

Venus is still in the Goldilocks zone, which is why it was expected that Venus would be covered with steaming jungles and inhabitable until we actually measured the temperature and it was such a surprise that it was so hot. This would have been even more true early in the Solar Systems history when the Sun itself was 25% cooler.
BTW, even the Earth would be an iceball at our distance from the Sun without the greenhouse effect which raises temperatures something like 40K

Re:The geology department is trying to... (0)

Anonymous Coward | about 5 months ago | (#46809023)

"BTW, even the Earth would be an iceball at our distance from the Sun without the greenhouse effect which raises temperatures something like 40K"

If this were true, why when you compare the temperatures on earth and venus at the same pressures, is the venus temp ~1.176x that of earth. This happens to be the temperature difference we would predict based on distance from the sun alone. I have read that venus' high temperature is caused by greenhouse effect, but also that the clouds reflect light thus preventing a greenhouse effect there. The theory does not seem to make sense or be able to explain the data I mention above.

Re:The geology department is trying to... (0)

Anonymous Coward | about 5 months ago | (#46812105)

If you want to ignore the effects of trapped heat, then just use the Stefan-Boltzmann law to find the equilibrium temperature of Earth. If you ignore Earth's albedo, you get a temperature just above freezing, and taking into account the albedo you get a temperature about -15 C, when the actual average surface temperature is about 15 C. The same could be done for Venus, It wouldn't be surprising that at the same pressure level you get the 1/sqrt(r_orbit) effect, since at the same pressure that means you have about the same amount of atmosphere above you in both cases. Although an amount of coincidence is involved because of the different compositions, and the comparison fails for comparing higher parts of the atmospheres since Venus lacks a stratosphere

Re:The geology department is trying to... (1)

Hognoxious (631665) | about 5 months ago | (#46807379)

"Some scientists think that plate tectonics are essential for life"

I think it are singular, but I might be wrong because I studied a physic and a small economic.

this makes no sense to me. (-1, Troll)

Noah Haders (3621429) | about 5 months ago | (#46806359)

things that make no sense: 1) that CO2 would be poisonous? 2) venus has no atmosphere because it is so close to the sun 3) it has a molten surface because it is so close, so there is no "crust". 4) it is like that planet in star wars. the one with the molten surface.

Re:this makes no sense to me. (1)

Anonymous Coward | about 5 months ago | (#46806425)

It doesn't make sense to you that a 96% CO2 atmosphere is poisonous? Really? How about Mercury? Does it have a molten surface? Why are there so many idiots and morons these days?

Re:this makes no sense to me. (1)

Anonymous Coward | about 5 months ago | (#46806451)

Poisonous is not always a question of composition but can be a question of amount.
Oxygen is toxic to humans if you bring the concentrations up high enough.
Increase the O2 even more and you have Apollo 1 all over again.

Re:this makes no sense to me. (2)

bluefoxlucid (723572) | about 5 months ago | (#46806491)

I want to see a model of a Venus carbon scrub. 96% CO2? Earth is 20% O2, 0.035% CO2. Venus has 3.5% nitrogen. If we brought the CO2 down to Earth levels, the atmosphere would be 1% CO2, 99% nitrogen. Obviously, instead, you'd have a ton of oxygen--but if you could find hydrogen, you could make vast amounts of O2.

I went to research this and ... someone has already worked it out. Bombarding Venus with hydrogen would produce a 3 bar atmosphere, 80% coverage with water, 10% of the water on the earth's surface but Venus is flat. Habitable. Probably not for humans, but we could continuously dump life there and it would eventually adapt. Building an ecosphere would be hard; it would be easier to seed with microbial life and wait a billion years. Rapid terraformation is hard; we could use a temporal bubble to do it, otherwise not so great.

Re:this makes no sense to me. (1)

atherophage (2481624) | about 5 months ago | (#46806507)

Plate tectonics is a theory (http://en.wikipedia.org/wiki/Plate_tectonics); one with a great many believers. Velikovsky writes Venus is hot because it is so young; having been a comet not that long ago, a theory too. An idea based upon another assumption, albeit one sold as fact, remains an idea.

Re:this makes no sense to me. (0)

Noah Haders (3621429) | about 5 months ago | (#46807207)

heliocentrism is also a theory taken as fact, and notbody is even trying to disprove it any more. geocentrism ftw, it's the only one that makes any sense.

Re:this makes no sense to me. (0)

Anonymous Coward | about 5 months ago | (#46807975)

heliocentrism is also a theory taken as fact, and notbody is even trying to disprove it any more. geocentrism ftw, it's the only one that makes any sense.

We've known for almost 100 years that heliocentrism isn't accurate.

Re:this makes no sense to me. (1)

dryeo (100693) | about 5 months ago | (#46808933)

Gravity is also a theory and yet hardly anybody argues about its existence.

Re:this makes no sense to me. (1)

cusco (717999) | about 5 months ago | (#46810445)

Velikovsky? How does his foolishness fit with your 'Electric Universe' foolishness?

Re:this makes no sense to me. (1)

dryeo (100693) | about 5 months ago | (#46812239)

Much as a broken clock is right twice a day, Velikovsky was the only one who predicted that Venus would be a furnace.

Re:this makes no sense to me. (5, Informative)

BitZtream (692029) | about 5 months ago | (#46806509)

A basic biology class will tell you that CO2 is poisonous to a great many things ... like everything that breaths oxygen.

http://en.wikipedia.org/wiki/H... [wikipedia.org]

The rest of your post could be solved if you opened any 3rd or 4th grade science book ... not sure what planet you're thinking of, but its not venus, which has both an atmosphere and a solid surface.

http://en.wikipedia.org/wiki/V... [wikipedia.org]

It makes no sense because you have absolutely no idea what you're talking about.

Re:this makes no sense to me. (1)

Noah Haders (3621429) | about 5 months ago | (#46807195)

there's a difference between something that's poisonous and something that suffocates you from lack of oxygen. for example, carbon monoxide is poisonous because it neutralizes your red blood cells, so you die even though the % is so low that it doesn't impact O2 %. So my question, is CO2 really poisonous or does it just cause suffocation?

Re:this makes no sense to me. (1)

cant_get_a_good_nick (172131) | about 5 months ago | (#46807301)

Though I don't know the exact mechanism, I'd say to watch Apollo 13. Watch how much effort they put in to the CO2 scrubbers, to remove carbon dioxide from the air. They had sufficient oxygen, it was the CO2 levels that were too high. That's what was making them sick.

Re:this makes no sense to me. (1)

Noah Haders (3621429) | about 5 months ago | (#46807651)

I don't need to watch Apollo 13 because I watched gravity. also Apollo 11 was the more successful one so why would I watch a movie about the less successful one???

Re:this makes no sense to me. (0)

Anonymous Coward | about 5 months ago | (#46808819)

Obvious troll is obvious. Go away, please.

Re:this makes no sense to me. (0)

Anonymous Coward | about 5 months ago | (#46807395)

Re:this makes no sense to me. (0)

Anonymous Coward | about 5 months ago | (#46807633)

As the partial pressure of CO2 increases, your blood has trouble getting rid of the CO2 in it. This happens long before the oxygen gets displaced, and you wouldn't be able to live in an environment that had the same amount of oxygen but much higher CO2. In effect, a lot of CO2 acts parallel to carbon monoxide, just it takes a lot more.

Re:this makes no sense to me. (3, Informative)

Anonymous Coward | about 5 months ago | (#46807659)

The atmosphere is 78% nitrogen, and we breath it just fine. But air of 5 - 10% carbon dioxide is far more than enough to kill you. This happens because carbon dioxide is toxic to humans and nitrogen is not. It has nothing to do with oxygen deprivation.

As anyone who has taken college level biology will know, the hemoglobin found in red blood cells has two functions. The first is to transport oxygen from the lungs to the rest of the body, because oxygen is needed for cellular respiration (mainly the electron transport chain). The second function is to remove CO2 from the body cells and send them to the lungs. CO2 is the byproduct of cellular respiration, so if red blood cells did not transport it out, it would quickly accumulate in the body and make it too acidic to function (carbon dioxide plus water makes carbonic acid). This is why it is so critical for hemoglobin to be able to transport CO2 out of the body. The problem is that since hemoglobin can bind both CO2 and oxygen, high CO2 levels will begin to "crowd out" oxygen and hog up all of the hemoglobin, leading to suffocation. But even though the atmosphere is 78% nitrogen, this does not happen with nitrogen because nitrogen is not able to bind to hemoglobin at all. Evolutionarily, there is no reason for hemoglobin to have this ability.

tl;dr It's not about lack of oxygen. CO2 is toxic, nitrogen is not even though there is much more of it.

Re:this makes no sense to me. (0)

Anonymous Coward | about 5 months ago | (#46808355)

The problem is that since hemoglobin can bind both CO2 and oxygen, high CO2 levels will begin to "crowd out" oxygen and hog up all of the hemoglobin, leading to suffocation.

You lost me here. If CO2 and O2 both bind equally to hemoglobin, then what causes CO2 to be "released" in favor of O2 in the first place? (i.e. what causes the exchange during a given breath?)

Re:this makes no sense to me. (1)

Anonymous Coward | about 5 months ago | (#46808489)

Simple differences in concentration, combined with differences in binding strength between the two molecules.
When there is less 'free' CO2 than O2, more O2 will bind to the available receptors. (Especially as it binds preferentially.)
As CO2 levels rise, less and less O2 is available to 'find' and bind to the receptors on hemoglobin, resulting in less and less O2 being transported into the body.
CO, on the other hand binds *much* more strongly than O2, and as a result, it takes very high concentrations of O2, and/or long periods of time to flush CO from the bloodstream.

Re:this makes no sense to me. (2, Informative)

Anonymous Coward | about 5 months ago | (#46808653)

To add onto the other AC's helpful response, you can think about it as a sort of diffusion process. When blood reaches the lungs, it (and the hemoglobin within it) is rich in carbon dioxide while the lungs are rich in oxygen, so CO2 diffuses out of the blood and into lungs and oxygen flows from the lungs to the blood. When blood reaches body tissues, the body tissues have lots of CO2 and little oxygen compared to the blood, so the CO2 flows from the tissue to the blood and oxygen in the opposite direction. As the other AC already said, CO2 has a much higher binding affinity for hemoglobin than oxygen, which is why it can be a deadly poison even at low concentrations.

Fun fact: breathing is actually more driven by the need to exhale CO2 than the need to inhale oxygen. This is part of the reason that swimmers continue to exhale while they are holding their breath underwater.

Re:this makes no sense to me. (1)

Hognoxious (631665) | about 5 months ago | (#46809769)

The law of mass action, you oik.

Re:this makes no sense to me. (1)

OneAhead (1495535) | about 5 months ago | (#46808975)

CO2 also reversibly "neutralizes your red blood cells"; the reason we're alive is that it only does so at a much higher concentration than CO. Once the CO2 level goes above about 10% for more than about 15 minutes, you'll likely suffer brain damage and/or death, no matter how much oxygen there is in the air.

Re:this makes no sense to me. (1)

cant_get_a_good_nick (172131) | about 5 months ago | (#46807741)

1) that CO2 would be poisonous?

Water in sufficient quantities is toxic. I don't even mean in the drowning sense, or the silly DiHydrogen Monoxide [dhmo.org] jokes, but if you have too much water, it can kill you. [nbcnews.com]

Nitrogen also works this way. Nitrogen in air, normal pressure, is fine. Nitrogen under pressure can kill you. [wikipedia.org]

Too much oxygen can make you space out.

There are a lot of things that follow this - if you think of normal doses of heat, or electricity, you're fine. If too much, you die. It doesn't take a lot of thinking to come up with examples.

Wow. Talk about ignorance. (5, Insightful)

mmell (832646) | about 5 months ago | (#46806847)

I mean here, not from the article's author.

If instead of yelling about how Mr. Bercovici's theory doesn't explain life, the Universe and everything we accept that he has provided a reasonable theory explaining one of the factors which led to the current difference between Earth and Venus, the conversation here might be more productive.

Yes, Venus gets considerably more energy from the Sun than Earth does. Yes, this alone could reasonably be expected to make it very different from Earth. Is that the only thing which caused Venus to be different from the Earth? If not, it might be interesting to know what other factors resulted in the differences we see - hence, the article exploring how plate tectonics may have contributed to the differences we see.

Oh, one last observation - Mr Bercovici has postulated a theory. I'm sure he started with a hypothesis for which he then sought supporting evidence, which he has provided. So far, sounds like good science to me.

Re:Wow. Talk about ignorance. (1)

Anonymous Coward | about 5 months ago | (#46807835)

I think most people here are taking issue with the journalist and not the researcher. She should read more Feynman if she really believes the tautological narrative presented in paragraph 3 and that simulation=reality as implied by the headline.

Venus assumed to be 200 degrees hotter? (4, Interesting)

erice (13380) | about 5 months ago | (#46807303)

From TFA:

the Venus model, which was a couple hundred Kelvin hotter,

So, how does it get so much hotter than Earth? It is certainly that much hotter now but that is attributed almost entirely to the greenhouse effect. However, the article earlier states:

Without plate tectonics, carbon would build up in the atmosphere. Venus, which does not have tectonics, shows the results: an atmosphere that is 96 percent carbon dioxide.

So, because plates did not form, Venus experienced a runaway greenhouse effect and high temperatures. But high temperatures are supposed to prevent plates from forming. A little circular, no?

Don't get me wrong: this is interesting work but it doesn't really answer the question of how Venus became the way it is . To close the gap, you need to assume that:
a) Venus started out 200K hotter though some other means (Proximity to the Sun is not generally considered sufficient for that)
-or-
b) Venus plate tectonics stalled early on for some other reason, allowing the greenhouse effect to take over.

Re:Venus assumed to be 200 degrees hotter? (1)

Anonymous Coward | about 5 months ago | (#46807707)

From the paper:

A similar exercise using hotter Venusian surface conditions permits
a comparison to Earth’s putative twin25–27.Using the same material properties
but a lithosphere temperature elevated by 200–400K above the
Earth-like case, the damage number D is reduced by a factor of about
10, and the healing numbers Ci and CI are increased by a factor of up to
10 (see Methods). In this case, as a downwelling migrates to various
positions (see Fig. 2), only very faint weak zones accumulate because
damage itself is weaker while healing is stronger, thereby resulting in
zones of passive divergence and strike-slip vorticity about an order of
magnitude weaker than the convergence rate. The final flowfield is dominated
by convergence, giving the appearance of a subduction-only surface.
This result provides a simple explanation for why Venus possibly
has subduction zones28, but no extant plate tectonics.

So they simply ran the simulation assuming higher temperature at the beginning. The paper does not appear to discuss CO2 at all. All of that greenhouse effect stuff seems to be an aside added by the journalist.

Without plate tectonics, carbon would build up in the atmosphere. Venus, which does not have tectonics, shows the results: an atmosphere that is 96 percent carbon dioxide. It's toxic. Yet Venus is about the same size and composition as our planet, so why doesn't it have plate tectonics?

I do not understand the purpose of this line about "It's toxic". It does not really have any meaning (toxic to what?) and is not related to the point of the article.

Compute Hours? (2)

nobdoor (1496229) | about 5 months ago | (#46807469)

"The model uses physics at the one-millimeter rock grain scale to explain how the whole planet behaves."

A 3,000 x 3,000 x 3,000 grid is considered very large for modern scientific models. Assuming they are working on a cartesian grid, and an earth diameter of 12,000 km, their model would be 12,000,000 x 12,000,000 x 12,000,000; twelve orders of magnitude larger than the biggest physical model I've ever heard of.

This cannot be the case.

Re:Compute Hours? (2)

crunchygranola (1954152) | about 5 months ago | (#46807939)

"The model uses physics at the one-millimeter rock grain scale to explain how the whole planet behaves."

A 3,000 x 3,000 x 3,000 grid is considered very large for modern scientific models. Assuming they are working on a cartesian grid, and an earth diameter of 12,000 km, their model would be 12,000,000 x 12,000,000 x 12,000,000; twelve orders of magnitude larger than the biggest physical model I've ever heard of.

This cannot be the case.

Whew! Its a good thing they never claimed they were doing any such thing.

"physics at the one-millimeter rock grain scale" does not mean that they were using a model grid of that same scale.

To show that the assumption that it must, or even should, is incorrect consider any engineering model that involves the effects of static friction.

The phenomena that cause static friction exist on the molecular and atomic level, and theoretical predictions of friction under arbitrary conditions need to be analyzed and calculated at that scale.

But once you have determined what the coefficient is under a given set of conditions, you only need to use the single number in a macro scale model.

That is what they did here. If you read TFA you will see that their macro model used coefficients calculated using the detailed physics.

Re:Compute Hours? (1)

cusco (717999) | about 5 months ago | (#46810497)

Thanks, that makes more sense. I also was wondering how the hell they managed to crunch the numbers for a grid that size, which from TFS sounds like what they were doing.

I wonder what assumptions they are making? (1)

grantspassalan (2531078) | about 5 months ago | (#46807515)

Since nobody was around billions of years ago, many assumptions have to be made about conditions on earth at that time. This is true even more so about Venus. About the only thing these “scientists” can say for sure is that the mathematics and programming of their computer models are likely correct. That is certainly not true about the original assumptions used as a starting point. As the saying goes: “garbage in, garbage out”.

Simulation != Reality (0)

Anonymous Coward | about 5 months ago | (#46807559)

"According to David Bercovici, a geophysicist at Yale who was an author on the paper, the model also shows how plate tectonics emerged on Earth but not on her twin."

I doubt the actual researcher said this. The model shows how plate tectonics could have emerged.

Just Right (1)

Baron von Daren (1253850) | about 5 months ago | (#46809287)

Just another example on how many factors affect a planet’s ability to support life not to mention sentient species and civilizations. The more we learn, the longer the list becomes (e.g. the right kind of star system with the right kind of star, the right planetary materials in the right zone, the right kind of magnetosphere, the right kind of moon, shepherd planets, the right kind of galaxy/cluster, the right place in place in the galaxy/cluster, the right kind of geological tectonics, the right kind of asteroid/comet hits, the right kind of mass extinctions and evolutionary histories, and so on).

The universe (not to mention a potential multiverse) certainly contains many planets capable of supporting civilizations, but the numbers are certainly bleaker than the old Drake equations.

Re:Just Right (1)

cusco (717999) | about 5 months ago | (#46810563)

The Drake Equation didn't come with any numbers pre-decided. Some of the numbers, such as rate of star formation, were known. Some, such as percentage of stars with planets and percentage of planets in the 'Goldilocks Zone', are only becoming known now. Others, such as the percentage of planets that give rise to life, are still unknown. You can plug any numbers you want into any of the variables.

Re:Just Right (1)

Baron von Daren (1253850) | about 5 months ago | (#46811889)

Indeed, but I wasn't commenting on the equation as much as the tendency to plug in optimistic numbers yielding estimates of tens of thousands of advanced civilizations in the Milky Way alone. I don't have the numbers handy (so my memory may be betraying me), but I believe that somewhere around 90% of stars, in our galaxy, reside in areas too violent to support life for the requisite periods of time regardless of all other factors. I'm not qualified in the least to say whether you facter that into R itself, or if fi is more appropriate. Either way, when you start trying to determine a sound value for ne considering myriad variables like magnetosphere, tectonics, temperature, sufficient H2O, etc., I'd guess N is orders of magnitude less than what was in vogue decades ago.
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