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Andre
Joined: 21 Jul 2007
Posts: 298
Location: Germany - The Nederlands
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 Posted: Mon Jul 30, 2007 9:11 am Post subject: The Venus idea |
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Several members know about this but I guess it can't hurt to rerun it.
It started all with an idea, where Earth's energy is in it's spinning, Venus energy appears to be is in it's heat. Could it be that Venus somehow converted it's spinning energy into heat?
But ideas need to be tested, you need a valid mechanism and proof, consistent with the idea and it's projections/predictions. And of course rigorous falsification attemps.
We have found a mechanism.
We have found plenty of supporting evidence "consistent with", in the search we also have found several mutually conflicting hypotheses, in different fields about the whereabouts of Venus, which basically suggest that they are invalid.
Although we have discussed many conflicting ideas, we have not encountered falsifying evidence. You cannot debunk a hypothesis with another hypothesis.
Here is the abstract of the unpublished writings. It's from 2004. I see that we need to update.
| Quote: | ABSTRACT.
Venus’ planetary "design" and its likely complicated orbit and spinning interactions in the past may have caused one or more breakouts of the planet’s inner core spinning axis in relation to the spin axis of the mantle. This may have happened billions of years ago and it may have had catastrophic results. We intend to demonstrate that this hypothesis may generally explain all enigmatic features of Venus simultaneously.
The precession cycles and obliquity cycles of Venus may have been in a chaotic resonance interaction in the distant past. This may have caused extreme obliquity changes of the planet’s mantle. Also, precession cycles add up here to generate a high rate of change of the spin axis of the mantle of the planet. The planet’s solid inner core may not have been stabilized enough to follow these spin axis changes, and its own, individual spin axis may have departed from alignment with the mantle spin axis. This may have caused a dramatic braking effect where the spinning energy of the planet was converted to heat, reducing the spinning of the planet significantly.
The surface of the planet shows several apparent signs of extreme heat, which has been attributed to runaway greenhouse gas effect. It is recognized however, that not all thermal features can be explained either by volcanism or by greenhouse gas effect therefore also radiogenic heating was introduced but there are no further indications for such a aberration from the Earth like composition. An extreme internal heat as caused by the internal braking of the inner core would explain these features far more easily. Also a significant volcanic activity in the early period that diminished gradually as the planet cooled, could also point in this direction.
The atmosphere of Venus contains carbon on about the same order of magnitude as the total Earth lithosphere. This could suggest that all Venus carbon is in its atmosphere, to be explained by a general heating of the complete planet, enough to reduce all limestone type of rocks in the crust to carbon dioxide and calcium oxides. Greenhouse models continue to pose several problems about the current thermal state of the planet. These problems cease to exist however with the notion that the heat is still residual from that the big brake.
Consequently, Venus’ current slow spin state, the extreme heat of the planet and its dense atmosphere, as well as its enigmatic geologic surface features could all be explained by a single mechanism: the big brake. |
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AstrumAspicio
Joined: 30 Jul 2007
Posts: 14
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| Posted: Tue Jul 31, 2007 6:18 am Post subject: Re: The Venus idea |
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| Andre wrote: | Several members know about this but I guess it can't hurt to rerun it.
It started all with an idea, where Earth's energy is in it's spinning, Venus energy appears to be is in it's heat. Could it be that Venus somehow converted it's spinning energy into heat?
But ideas need to be tested, you need a valid mechanism and proof, consistent with the idea and it's projections/predictions. And of course rigorous falsification attemps.
We have found a mechanism.
We have found plenty of supporting evidence "consistent with", in the search we also have found several mutually conflicting hypotheses, in different fields about the whereabouts of Venus, which basically suggest that they are invalid.
Although we have discussed many conflicting ideas, we have not encountered falsifying evidence. You cannot debunk a hypothesis with another hypothesis.
Here is the abstract of the unpublished writings. It's from 2004. I see that we need to update.
| Quote: | ABSTRACT.
Venus’ planetary "design" and its likely complicated orbit and spinning interactions in the past may have caused one or more breakouts of the planet’s inner core spinning axis in relation to the spin axis of the mantle. This may have happened billions of years ago and it may have had catastrophic results. We intend to demonstrate that this hypothesis may generally explain all enigmatic features of Venus simultaneously.
The precession cycles and obliquity cycles of Venus may have been in a chaotic resonance interaction in the distant past. This may have caused extreme obliquity changes of the planet’s mantle. Also, precession cycles add up here to generate a high rate of change of the spin axis of the mantle of the planet. The planet’s solid inner core may not have been stabilized enough to follow these spin axis changes, and its own, individual spin axis may have departed from alignment with the mantle spin axis. This may have caused a dramatic braking effect where the spinning energy of the planet was converted to heat, reducing the spinning of the planet significantly.
The surface of the planet shows several apparent signs of extreme heat, which has been attributed to runaway greenhouse gas effect. It is recognized however, that not all thermal features can be explained either by volcanism or by greenhouse gas effect therefore also radiogenic heating was introduced but there are no further indications for such a aberration from the Earth like composition. An extreme internal heat as caused by the internal braking of the inner core would explain these features far more easily. Also a significant volcanic activity in the early period that diminished gradually as the planet cooled, could also point in this direction.
The atmosphere of Venus contains carbon on about the same order of magnitude as the total Earth lithosphere. This could suggest that all Venus carbon is in its atmosphere, to be explained by a general heating of the complete planet, enough to reduce all limestone type of rocks in the crust to carbon dioxide and calcium oxides. Greenhouse models continue to pose several problems about the current thermal state of the planet. These problems cease to exist however with the notion that the heat is still residual from that the big brake.
Consequently, Venus’ current slow spin state, the extreme heat of the planet and its dense atmosphere, as well as its enigmatic geologic surface features could all be explained by a single mechanism: the big brake. |
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Interesting. Do remember, a planet must maintain thermal equilibrium as well.
The Earth does so thru tectonic plate action and inner mantel convection. Venus has no such mechanism, so it appear that entire catastrophic continent sized subduction is the likely methodology there.
Also the Earth has a spinning core (not at the same velocity as the surface) which produces the strong magnetic field surrounding the Earth.
Since neither Venus nor Mars has such a field, it is believed (and there is evidence to support this) that neither planet has a rotating core.
I am running out of time - will post more tomorrow on this. 
(If you want that is)
Last edited by AstrumAspicio on Wed Aug 01, 2007 7:45 am; edited 1 time in total |
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NileQueen
Joined: 21 Jul 2007
Posts: 77
Location: southern Indiana/Cincinnati Ohio
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| Posted: Tue Jul 31, 2007 10:45 am Post subject: Re: The Venus idea |
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| AstrumAspicio wrote: |
(If you want that is) |
Go ahead. |
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AstrumAspicio
Joined: 30 Jul 2007
Posts: 14
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| Posted: Wed Aug 01, 2007 7:50 am Post subject: Re: The Venus idea |
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| NileQueen wrote: | | AstrumAspicio wrote: |
(If you want that is) |
Go ahead. |
I dragged two texts off my shelf and am going thru them as we speak:
Origin and Evolution of Planetary and Satellite Atmospheres - S. K. Atreya, J. B. Pollack, and M. S. Matthews
Venus - D. M.Hunten, L. Colin, T.M. Donahue, and V. I. Moroz
I am not a planetary atmospheric scientist, nor do I play one on TV. So I need to read up on this before I insert foot in mouth. |
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Andre
Joined: 21 Jul 2007
Posts: 298
Location: Germany - The Nederlands
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| Posted: Wed Aug 01, 2007 10:09 am Post subject: Re: The Venus idea |
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| AstrumAspicio wrote: |
Interesting. Do remember, a planet must maintain thermal equilibrium as well. |
Thermal equilibrium pertaining the surface is only true if the temperature of a planet is constant. Since Venus came down from at least 1000K, (see this) it is conceavable that there is no thermal equilibrium. There have been issues about that in the past. Reason perhaps that's so silent around the Venus Express (the other thread). Explaining a cooling planet is peanuts with the big brake hypothesis.
| Quote: | | The Earth does so thru tectonic plate action and inner mantel convection. Venus has no such mechanism, so it appear that entire catastrophic continent sized subduction is the likely methodology there. |
The generation of heat in the Earth core may partly be attributed to the same mechanism, core mantle friction, due to different precession forcings of the solid inner core and mantle. James Vanyo, (also here) did some calculations but had problems with the size of the solid inner core. I would think that this is due to the excess heat generated.
| Quote: | Also the Earth has a spinning core (not at the same velocity as the surface) which produces the strong magnetic field surrounding the Earth.
Since neither Venus nor Mars has such a field, it is believed (and there is evidence to support this) that neither planet has a rotating core. |
I think that Mars had a minute magnetic field where Venus has none, which suggests indeed that there is no thermal convective activity in the core. This is consistent with the spinning with precession as source for the geothermal activity.
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Baywax
Joined: 23 Jul 2007
Posts: 113
Location: Pacific West Coast
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| Posted: Thu Aug 02, 2007 11:59 pm Post subject: |
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Andre, is the "internal braking of the inner core " that may be taking place in Venus a natural, physical tendancy to reverse the present rotation to a rotation that is counter to its orbital spin?
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billiards
Site Admin
Joined: 21 Jul 2007
Posts: 81
Location: London, UK
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| Posted: Fri Aug 03, 2007 12:35 am Post subject: |
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Andre will know from our own private correspondence that I am not a huge fan of this "internal brake" theory.
From my understanding we have two observations, the second of which is less robust:
1) Venus is not spinning very fast at all, taking 243 earth days to complete one rotation.
2) Venus is hotter than it should be on the basis of its CO2 atmospheric greenhouse effect alone.
From my understanding (and correct me if I'm wrong), Andre is suggesting that the fact that Venus is spinning so slowly explains the additional heat by way of an "internal brake". The exact mechanics of this internal brake remain somewhat unclear to me, although it seems that there is a fluid core (possibly with a solid inner core like the Earth?) that by "chaotic resonance interaction" is converting spinning energy into heat energy.
The first most obvious problem is that of where the energy must have come from in the first place to get the planet spinning. Venus has no moons to speak of, so with no moon forming impacts, why would Venus have this spinning energy in the first place?
Surely it would be a lot more elegant to explain observation (1) - that Venus isn't really spinning, by saying that it was never spinning so why should it be now? It seems to me at least a little farfetched to suggest that this internal brake is somehow converting spinning energy into heat with almost 100% efficiency!
The second problem, which is far more subtle has to do with the absence of a magnetic field. Surely if the core was spinning around crazily, there would be sufficient energy to drive some kind of geodynamo, thus we would expect to see a magnetic field, but alas there is not one. To me, this suggests for reasons that I will not go into, that either Venus has a completely fluid core, which is rather calm. Or alternatively, Venus has a completely solidified core. Neither of these would fit the "internal brake" hypothesis.
As for the source of this additional heat, I imagine that it could be due to some "enhanced greenhouse effect" (mechanism unknown), or perhaps (most probably) it is of radiogenic origin. Just to finish, there is another mystery on Venus, its atmosphere is super-rotating at a rate of about one-rotation every four earth days, just why this is is anybody's guess...
reference: http://www.realclimate.org/index....hives/2006/04/lessons-from-venus/ |
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NileQueen
Joined: 21 Jul 2007
Posts: 77
Location: southern Indiana/Cincinnati Ohio
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| Posted: Fri Aug 03, 2007 2:11 am Post subject: |
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| billiards wrote: | Andre will know from our own private correspondence that I am not a huge fan of this "internal brake" theory.
From my understanding we have two observations, the second of which is less robust:
1) Venus is not spinning very fast at all, taking 243 earth days to complete one rotation.
2) Venus is hotter than it should be on the basis of its CO2 atmospheric greenhouse effect alone.
From my understanding (and correct me if I'm wrong), Andre is suggesting that the fact that Venus is spinning so slowly explains the additional heat by way of an "internal brake". The exact mechanics of this internal brake remain somewhat unclear to me, although it seems that there is a fluid core (possibly with a solid inner core like the Earth?) that by "chaotic resonance interaction" is converting spinning energy into heat energy.
The first most obvious problem is that of where the energy must have come from in the first place to get the planet spinning. Venus has no moons to speak of, so with no moon forming impacts, why would Venus have this spinning energy in the first place?
Surely it would be a lot more elegant to explain observation (1) - that Venus isn't really spinning, by saying that it was never spinning so why should it be now? It seems to me at least a little farfetched to suggest that this internal brake is somehow converting spinning energy into heat with almost 100% efficiency!
The second problem, which is far more subtle has to do with the absence of a magnetic field. Surely if the core was spinning around crazily, there would be sufficient energy to drive some kind of geodynamo, thus we would expect to see a magnetic field, but alas there is not one. To me, this suggests for reasons that I will not go into, that either Venus has a completely fluid core, which is rather calm. Or alternatively, Venus has a completely solidified core. Neither of these would fit the "internal brake" hypothesis.
As for the source of this additional heat, I imagine that it could be due to some "enhanced greenhouse effect" (mechanism unknown), or perhaps (most probably) it is of radiogenic origin. Just to finish, there is another mystery on Venus, its atmosphere is super-rotating at a rate of about one-rotation every four earth days, just why this is is anybody's guess...
reference: http://www.realclimate.org/index....hives/2006/04/lessons-from-venus/ |
billiards et al.,
| Quote: | | The pressure of Venus' atmosphere at the surface is 90 atmospheres (about the same as the pressure at a depth of 1 km in Earth's oceans). It is composed mostly of carbon dioxide. There are several layers of clouds many kilometers thick composed of sulfuric acid. These clouds completely obscure our view of the surface. This dense atmosphere produces a run-away greenhouse effect that raises Venus' surface temperature by about 400 degrees to over 740 K (hot enough to melt lead). Venus' surface is actually hotter than Mercury's despite being nearly twice as far from the Sun. |
http://www.nineplanets.org/venus.html
My take on this is...
Venus had a near meltdown 500-700 million years ago, and one can see the volcanic structures on the surface. CaCO3 was burned off and that's why there is so much CO2 in the atmosphere now. Venus' atmospheric situation is not a runaway greenhouse effect by any means. The planet is rotating so slowly retrograde (backwards to all the other planetary spins) and one would expect the long Venus night to have some cooling effect. Not so, as there is still heat emanating from the surface.
The friction heat may have come from conflict between the crust/mantle spin axis and the inner core axis, as the core grew bigger, as the planet aged. Although there could be other reasons for the retrograde spin, the burnoff of CaCO3 is hard to explain with i.e. an impact, for example. Why does Venus still have an atmosphere? Mars doesn't have much of one.
| Quote: |
Mars has a very thin atmosphere composed mostly of the tiny amount of remaining carbon dioxide (95.3%) plus nitrogen (2.7%), argon (1.6%) and traces of oxygen (0.15%) and water (0.03%). The average pressure on the surface of Mars is only about 7 millibars (less than 1% of Earth's), but it varies greatly with altitude from almost 9 millibars in the deepest basins to about 1 millibar at the top of Olympus Mons. But it is thick enough to support very strong winds and vast dust storms that on occasion engulf the entire planet for months. Mars' thin atmosphere produces a greenhouse effect but it is only enough to raise the surface temperature by 5 degrees (K); much less than what we see on Venus and Earth. |
http://www.nineplanets.org/mars.html |
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Andre
Joined: 21 Jul 2007
Posts: 298
Location: Germany - The Nederlands
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| Posted: Fri Aug 03, 2007 8:19 am Post subject: |
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Thanks for your thoughts Jack, it gives a chance to address the questions directly. In addition to NQ's observations:
| billiards wrote: |
The first most obvious problem is that of where the energy must have come from in the first place to get the planet spinning. Venus has no moons to speak of, so with no moon forming impacts, why would Venus have this spinning energy in the first place? |
Conservation laws, conservation of momentum and energy. Whatever way the planetary system was formed, I guess the current idea is a end result of a supernovae. But all particles have energy and momentum (including angular momentum). Contraction of particles to form a planet also cause it to spin up, like the spinning ice skater. Starting with a slightly spinning nebulae, you would end up with orbiting planets all spinning in the same direction of the orbit. That's why Venus logically should be spinning in a comparable way to Earth and Mars.
| Quote: | | It seems to me at least a little farfetched to suggest that this internal brake is somehow converting spinning energy into heat with almost 100% efficiency! |
Actually the transfer of mechanical energy (movement) to heat is considered to be the opposite of efficiency. brakes that bring a car to a full stop are the same perfect effenciency killers and heat up accordingly.
Detailed modelling about Venus spin down has been done by Correia Laskar and Neron de Surgy:
http://www.imcce.fr/Equipes/ASD/preprints/prep.2002/venus1.2002.pdf
http://www.imcce.fr/Equipes/ASD/preprints/prep.2002/venus2.2002.pdf
Indeed they assume core mantle friction during the chaotic resonance precession and obliquity cycles to be a main cause of the spin down, however they cannot explain a greater initial spin cycle of 3,5 days to reach the current end state whereas the conservation of momentum principle would suggest an initial spin rate of around 18 hours like Earth.
Then again, the only difference with us is that they do not consider a possible break out of the inner core spin axis and they overlook that their mechanism also should transfer rotating energy into heat.
| Quote: | | The second problem, which is far more subtle has to do with the absence of a magnetic field. .....To me, this suggests for reasons that I will not go into, that either Venus has a completely fluid core, which is rather calm. Or alternatively, Venus has a completely solidified core. Neither of these would fit the "internal brake" hypothesis. |
On the contrary, they are fully consistent. Perhaps you confuse the before... and after... state. I agree that venus is likely to have a completely solidified or completely liquid core now, which are calm, not generating liquid iron convection cells, which are thought to cause the Earth magnetism. So if the core is not convecting, stable, that means that the current thermal gradient is small enough to prevent convection, which also means that there is no (more) need for plate tectonics.
Compare that the Earth, the convecting core needs to get energy from somewhere. I linked to the Vanyo papers in a previous post to demonstrate that the core mantle friction due to different precessions could have been a heat source. Venus without rotation also has no core mantle friction, hence no energy source to produce convection heat and hence no magnetism.
| Quote: | | As for the source of this additional heat, I imagine that it could be due to some "enhanced greenhouse effect" (mechanism unknown), or perhaps (most probably) it is of radiogenic origin. |
The fun of our little (inductive) idea is that it explains more things than the (deductive) hypotheses for all the seperate problems.
| Quote: | | Just to finish, there is another mystery on Venus, its atmosphere is super-rotating at a rate of about one-rotation every four earth days, just why this is is anybody's guess... |
Indeed, there have been ideas about heating and cooling pressure gradients between the sun side and the shadow side. But then again, why isn't Venus surface not reacting to those temperature cycles. It's not that the poles or the shadow side are cooler. The temperature is only being dependent on the geography, the lower the hotter. The Venus Express found that out.
But then again the big brake only works for the solid part of the planet. If you would stop the Earth like that, its atmosphere would keep spinning for a while.
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Bystander
Joined: 23 Jul 2007
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| Posted: Fri Aug 03, 2007 5:12 pm Post subject: |
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| Rather than waste a whole lot of time on this, someone want to put up some numbers? Compare rotational energy to radioactive heat over 4 Ga, viscosity of silicate melts to torques required for "the mechanism," and then we can put it on the scrap heap. |
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Andre
Joined: 21 Jul 2007
Posts: 298
Location: Germany - The Nederlands
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| Posted: Sat Aug 04, 2007 8:25 am Post subject: |
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| Bystander wrote: | | Rather than waste a whole lot of time on this, someone want to put up some numbers? Compare rotational energy to radioactive heat over 4 Ga, viscosity of silicate melts to torques required for "the mechanism," and then we can put it on the scrap heap. |
Did the back of envellope numbers some time ago. I'll try to find them back. Rotational energy of Earth is enough to heat it into nuclear fusion ranges, need a few billion years to get rid of that.
Complex reconstructions of the actual mechanism would see some difficulties with estimating parameters. I seem to remember that the estimates for the viscosity of the outer core range 10 orders of magnitude.
Might also an idea to run the 40K radiogenic heat idea and see if the ~250K cooling in the last billion years is consistent with that.
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Bystander
Joined: 23 Jul 2007
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| Posted: Sat Aug 04, 2007 6:18 pm Post subject: |
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| Andre wrote: | | (snip)Did the back of envellope numbers some time ago. I'll try to find them back. Rotational energy of Earth is enough to heat it into nuclear fusion ranges, need a few billion years to get rid of that. |
100 K vs. 10-100 million K --- 5-6 orders of magnitude pretty well finishes the hypothesis. You want help finding the error, put the calculation up, and we'll go over it.
| Quote: | | Complex reconstructions of the actual mechanism would see some difficulties with estimating parameters. I seem to remember that the estimates for the viscosity of the outer core range 10 orders of magnitude. |
"No parameters = no mechanism." Viscosity? Pick any number you want, and a thickness for the sheared layer, call it laminar flow, and do the calculation; if you need superfluid helium to decouple the core from the mantle for the length of time necessary to do the differential precession, you're reasonably certain the idea ain't worth pursuing.
| Quote: | | Might also an idea to run the 40K radiogenic heat idea and see if the ~250K cooling in the last billion years is consistent with that. |
Did that for you a couple years back on Pf --- remember?
Climate? Yes. Climate data? Yes. Historical climate data? Yes. "Questionable" hypotheses? Nah --- leave 'em to Omni. |
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Andre
Joined: 21 Jul 2007
Posts: 298
Location: Germany - The Nederlands
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| Posted: Sun Aug 05, 2007 8:13 pm Post subject: |
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| Bystander wrote: | | Andre wrote: | | (snip)Did the back of envellope numbers some time ago. I'll try to find them back. Rotational energy of Earth is enough to heat it into nuclear fusion ranges, need a few billion years to get rid of that. |
100 K vs. 10-100 million K --- 5-6 orders of magnitude pretty well finishes the hypothesis. |
Recall the model of Correia et al, they brake Venus with core mantle friction and atmospheric tidal friction during the chaotic resonance period. Their numerical simulations show that the intial spin rate could not have exceeded 3.5 days. So they were nowhere near the 18 hours of McDonald 1963 (I think it was who made those initial spin calculations. But he assumed a uniformly divided homogenous spinning dust cloud.
So I'll fool around a bit with excel and try to approximate which initial spinning could be feasible to reach this heat gradient 300 degrees in the last billion years.
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