Unexpectedly slow motions below the Sun's surface

Jul 20, 2012
Pattern of convection at the surface of the Sun observed by the HMI instrument on board of SDO. Credit: MPI for Solar System Research /NASA

(Phys.org) -- The interior motions of the Sun are much slower than predicted. Rather than moving at the speed of a jet plane (as previously understood) the plasma flows at a walking pace. The result of this new study, whose lead author is from the Max Planck Institute for Solar System Research, will be published in an upcoming issue of Proceedings of the National Academy of Sciences (PNAS). The scientists use observations of solar oscillations from NASA's Solar Dynamics Observatory (SDO) to see into the Sun's interior. As Laurent Gizon and Aaron C. Birch from the Max Planck Institute for Solar System Research comment in the same issue of PNAS, these new observations demonstrate the unique capabilities of helioseismology with SDO to probe the mysteries of the deep solar interior.

In its outermost third, the Sun behaves like a simmering pot of water: heat from below causes the plasma to rise to the surface where it is cooled and descends back down into the interior. This mechanism, named convection, transports energy outward and controls the Sun’s structure and evolution.

In its outermost third, the Sun behaves like a simmering pot of water: heat from below causes the plasma to rise to the surface where it is cooled and descends back down into the interior. This mechanism, named convection, transports energy outward and controls the Sun’s structure and evolution.

The scientists, led by Shravan Hanasoge from Max Planck Institute for Solar System Research, were now for the first time able to constrain the flows deep within the convection layer from direct observations of the Sun’s surface with the help of helioseismology. Helioseismology is similar to Earth seismology. “We observe oscillations of the solar surface and use them to infer properties, such as flows, in the solar interior”, explains Laurent Gizon, director of the Department “Physics of the Interior of the Sun and Sun-like Stars” at the Max Planck Institute for Solar System Research  and Professor at the Institute for Astrophysics at the University of Göttingen.

Plasma flows with less than one metre per second 
The team of scientists from the Max Planck Institute for Solar System Research, Princeton University, NASA’s Goddard Flight Center and New York University was able to determine the flow velocities at a depth of 55000 kilometres, which is eight percent of the solar radius. Surprisingly, the flow velocities of the plasma were found to be less than a few meters per second. Gizon puts this into perspective saying “This is a hundred times less than predicted by numerical models of solar convection”.

The key to these new results was data from ’s space probe SDO, which has been observing the Sun’s surface since early 2010. The scientists analysed data from the Helioseismic and Magnetic Imager (HMI) onboard SDO. The analysis was only possible due to the combination of high resolution and full spatial coverage of the observations. The huge amount of data collected by HMI  - thousands of high-resolution images of the whole Sun per day - are archived and processed in the German Data Center for SDO hosted at the Max Planck Institute for Solar System Research, a unique facility in Europe.

Acoustic waves in the sun reveal the velocity of convection currents

HMI measures the velocity of the Sun's surface. When a solar acoustic wave trapped within the Sun reaches the surface, it causes the surface to move – and can thus be detected by HMI. In this way, the scientists were able to measure the time it takes for solar acoustic waves to travel from a point on the solar surface through the interior to another point on the surface. Convective flows affect the speed of propagation of the waves. Hence, it is possible to learn about the velocities of the convective flows in the solar interior from measurements of wave travel times. Modelling the interaction of solar acoustic waves with convection is a topic of current research, undertaken within the German Research Foundation’s Collaborative Research Center “Astrophysical flow instabilities and Turbulence” at the Max Planck Institute for Research  and the University of Göttingen.

Gizon says “The unexpectedly small velocities measured using helioseismology are the most noteworthy helioseismology result since the launch of HMI”. Adds Birch, “There is no clear way to reconcile the observations and theory”. Gizon then concludes “This result not only sheds a new light on the Sun – but also on our current inability to understand one of the most fundamental physical processes in the Sun and stars: ”.

Explore further: Successful engine test enables SpaceX Falcon 9 soar to space station in Jan. 2015

More information: Shravan M. Hanasoge, et al., Anomalously weak solar convection, Proceedings of the National Academy of Sciences, July 24 2012, 109, 30 (published online ahead of print June 4) doi:10.1073/pnas.1206570109

Laurent Gizon and Aaron C. Birch, Helioseismology challenges models of solar convection, Proceedings of the National Academy of Sciences, July 24 2012, 109, 30

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HannesAlfven
2.3 / 5 (18) Jul 20, 2012
That last paragraph is striking.

This observation flies in the face of very strong convictions about what the Sun is, and we can expect that it will therefore be completely ignored by many who prefer to mindlessly defend the textbook theory. In our attempt to manufacture models of the Sun which conform to our pre-existing beliefs about what the Sun actually is, those models will now have to be made yet more complex and reliant upon exotic, new, invisible science.

Eventually, over time, the notion that the Sun might be powered externally, with something like an electron drift from the heliopause, will start to look mundane compared to where this current model is headed.

Researchers do not lightly say things like, "There is no clear way to reconcile the observations and theory." What he's saying is that the thermonuclear theory has dead-ended. The real question here is if people care enough about the scientific method to listen to it when it does not suit their preferred beliefs.
A2G
3.8 / 5 (13) Jul 20, 2012
Hannes, So the researcher quoted is pointing out the problems with what they found and the current theories about the sun. Then you still find a way to see conspiracy in it?

What is wrong with you EU people? They point out that there are problems with current theories and you still rant. Do you not understand how science works.

I have seen the EU theories. Know them very well. But although you make some points, the way in which you present things does not fly either. If I hear Birkeland currents one more time from one of your cult followers I will scream.

Then as for you Hannes et al. Answer this:

The real question here is if ELECTRIC UNIVERSE people care enough about the scientific method to listen to it when it does not suit their preferred beliefs.
dtyarbrough
1.3 / 5 (13) Jul 20, 2012
Read STARS http://www.scribd...97/STARS and THE PROBLEMS WITH FUSION http://www.scribd...H-FUSION
baudrunner
1.4 / 5 (10) Jul 20, 2012
"In its outermost third, the Sun behaves like a simmering pot of water: heat from below causes the plasma to rise to the surface where it is cooled and descends back down into the interior."
and then...
"heat from below causes the plasma to rise to the surface where it is cooled and descends back down into the interior"
This conforms to - nay, proves - the Iron Mantle Theory of the sun, in that those acoustic oscillations echo back into the interior off its surface. The atmosphere is relatively thin, yet hot, and the surface of the iron sphere is the coolest layer in the sun.

HannesAlfven
2.8 / 5 (13) Jul 20, 2012
@A2G:

The mistake which you (and many others) make is in clinging to the term "conspiracy". You use the term because it conjures up a ridiculous image. But, in the process, you confuse yourself. What in the world is actually ridiculous about authoritarianism -- large organizations using their power to undermine competitors? That is the term which you should be using. Others might prefer "the sociology of science" -- a legitimate field of inquiry. After all, science is most fundamentally an organization of people. And anybody can go through the large number of physorg's psychology press releases and witness that humans are subject to many irrational behaviors. The truth is that thinking like a scientist does not come naturally to people, and the point at which the bias enters into science is consistently at the inferential step.

It is purely your own prerogative to ignore all of this, and replace it with a table circled by men wearing black glasses.
Bewia
2.1 / 5 (7) Jul 20, 2012
I seriously doubt that the solar convection is so slow. We can observe it easily with telescope. The flow within the granules can reach supersonic speeds of more than 7 km/s (15,000 mph) and produce sonic "booms" and other noise that generates waves on the Sun's surface. The continuity equation would require the similar speed even at deeper depth.
Bewia
2.1 / 5 (7) Jul 20, 2012
In addition, there is a mechanism of solar cycles, based on periodical switching of plasma currents beneath the surface of Sun. If the plasma would circulate so slowly, this model couldn't work at all. The more probable explanation would be, that the models of plasma speed based on sound wave spreading are wrong in similar way, like the misinterpretation of Michelson-Morley experiment before years. This experiment considered, that the light is propagating trough vacuum like the sound through air in longitudinal waves, whereas it's spreading like the ripples along membranes of foam in transverse waves. The spreading of such ripples is affected with motion of (reference frame of) environment very slightly, so that the speed of plasma circulation may be way higher - but the spreading of waves isn't affected with it. They're moving like the capillary ripples at the water surface.
Bewia
Jul 20, 2012
This comment has been removed by a moderator.
HannesAlfven
2.8 / 5 (11) Jul 20, 2012
@A2G:

From Jeff Schmidt's Disciplined Minds, a critique of the physics PhD program by a 19-year editor at Physics Today, page 35:

"The failure of professionals to question the politics built into their work serves the interests of those who have power in society and helps maintain the social and economic status quo. But refraining from questioning doesn't look like a political act, and so professionals give the appearance of being politically neutral in their work ... Nevertheless, the public is becoming increasingly savvy about at least one way in which professionals support the system through their work. People are beginning to understand that the intellectual worker's "professional judgment" or "expert opinion" is not objective as as it claims, but rather favors the interest of his or her employer."
HannesAlfven
3 / 5 (12) Jul 20, 2012
From an interview with Schmidt at http://www.julesn...6489.htm

"It seemed like the best of my fellow graduate students were either dropping out or being kicked out. And by best, those were the most concerned about other people and seemed less self-centered, LESS NARROWLY-FOCUSED, most friendly people...they seemed to be handicapped in the competition. They seemed to be at a disadvantage not only because their attention was divided, but because their concerns about big picture issues like justice and the social role of the profession and so on, CAUSED THEM TO STOP AND THINK AND QUESTION, whereas their UNQUESTIONING GUNG-HO CLASSMATES just plowed right through with nothing to hold them back. As I mentioned, theres about a 50% drop-out rate for students entering University programs in all fields; and what I found was that this weeding out is NOT POLITICALLY NEUTRAL. To put it bluntly, the programs favor ASS-KISSERS."
TheGhostofOtto1923
3.8 / 5 (17) Jul 20, 2012
It could be because the sun is made of very hot iron. Or neutronium I'm not sure.
Michael Mozina
2.1 / 5 (7) Jul 20, 2012
It won't be long before the mainstream realizes the full implications of these findings. Not only has the mainstream lost it's power source in terms of explaining solar flares, it's now highly unlikely that mass separation does not occur in the sun. Goodbye mainstream solar theory, hello Birkeland's cathode sun model.
Bewia
3.7 / 5 (6) Jul 20, 2012
..Goodbye mainstream solar theory, hello Birkeland's cathode sun model.
The fact, mainstream physics has a problem with explanation of some phenomena isn't sufficient reason to consider the alternative models at the moment, when they cannot explain it too. These naive theories have nothing to say to the above finding in the same way, like the mainstream solar theory. You understand, what happens here - or you don't. If you have nothing to say about article subject, why to say it just here?
ROBTHEGOB
3.9 / 5 (12) Jul 21, 2012
The truth is that inside the sun are squirrels running on treadmills to keep it going; they just don't go as fast as we thought they did. My theory is as good as some of yours.
MarkyMark
4.2 / 5 (5) Jul 21, 2012
Perhaps the sun is made or iron?

J/k

Bet Oliver would love this article tho.
10thman
2.6 / 5 (5) Jul 21, 2012
The thing that gets me about "mainstream" physics and the Standard Model is that every time observation does not support theory, instead of proposing a new theory that comports with observation, all effort is put into mathematical band-aids to preserve appearances, much like Ptolemy's epicycles. Physics seems stalled and in thrall to ever more impossible physical entities and explanations. What ever happened to Occam's razor? It sure got dull during the 20th Century. One simple exasperating example is the insistence on relating charged particle velocity to temperature alone instead of considering acceleration by an electric field, especially when motion is uniform instead of random. That's just one item in a a very long list.
Bewia
3 / 5 (2) Jul 21, 2012
Come on, the consideration of electric field inside of Sun doesn't explain the low speed of plasma convection observed at least a bit.

I can agree with you, that the proponents of mainstream physics often promote their concepts blindly with no connection to common sense and logics. But you're doing exactly the same by now - just from the opposite side of doors. In another words, you're doing the very same mistake, which you're trying to criticize by now. Why not to focus to physics instead of politics?
TheGhostofOtto1923
4.1 / 5 (14) Jul 21, 2012
Perhaps the sun is made or iron?

J/k

Bet Oliver would love this article tho.
A month or so ago pussy referenced a blog which just happened to have some very recent posts from oliver, which makes me wonder just who or what the obviously phony multi-sockpuppet pussy/ritchieguy/pirouette/russkiye really is.
Michael Mozina
1 / 5 (1) Jul 21, 2012
>>>>>Bewia: The fact, mainstream physics has a problem with explanation of some phenomena isn't sufficient reason to consider the alternative models at the moment, when they cannot explain it too.

FYI, Birkeland's cathode solar model is the only model that successfully predicted the existence electrical discharges in solar atmosphere which is not dependent upon convection (at all) and is not externally powered as with Juergen's model.

If you were correct that Birkeland's model didn't explain solar flares without convection, I'd agree with you. Unfortunately you're just wrong on that point.
Jitterbewegung
1 / 5 (3) Jul 22, 2012
Very interesting, if the walking pace movement theu mention is as slow as one cm per second then I would like to speculate that the ESA have found the gravity waves they mention in the link below. This would mean that gravity causes the motion.
What do you readers think?

http://www.google...eLAeDbhw
GSwift7
4 / 5 (4) Jul 23, 2012
This would mean that gravity causes the motion.
What do you readers think?


Ummmm, no. Gravity does cause convection, but convection is not "gravity waves". Look up flames in microgravity on youtube, and see what flame looks like when there's no convection if you wanna see something cool.

Researchers do not lightly say things like, "There is no clear way to reconcile the observations and theory." What he's saying is that the thermonuclear theory has dead-ended.


OMG, relax. Take a deap breath. Calm down. Breath into a paper bag for a few seconds.

If we tossed out every theory we can't model perfectly, then we would be back to stone tools. This observation just shows that the convection we expected is there, but it is behaving somehow differently than we though. Perhaps it's just the structure we picture wrong, who knows.
GSwift7
1 / 5 (1) Jul 23, 2012
continued:

Perhaps the structure is just more complicated than we thought. Perhaps the net speed is only walking speed, but maybe that's because the net is a product of two nearly opposite flows. By observing the accoustic waves in the manner above, we only get a rough picture of the internal structure that composes the net properties.

Someone mentioned the Razor postulate above. In that sense, throwing the consensus away just because of one new observation doesn't make sense. The simplest solution is to figure out which parts of our current understanding don't fit this observation, then figure out how to make observations that clear up the mystery.

I'm in favor of the system just being more complex than our models currently account for. The models already kinda cheat on the turbulence because it's too hard to model in much detail.
Torbjorn_Larsson_OM
3.7 / 5 (3) Jul 23, 2012
Ha, an electronic universe crackpot describing 'mindless' parroting. You can accept or reject solar physics, but accepting it is a thoughtful act.

It must hurt an EU-pot that the plasma convection is a lot less powerful than earlier thought.

@ baudrunner:

"the Iron Mantle Theory".

Another 'theory' that hasn't passed peer review? And how do you propose to test your theory? Where is the physics in "acoustic oscillations echo back" as opposed to a solar physics model, and how does it accord with these observations?
Torbjorn_Larsson_OM
3.7 / 5 (3) Jul 23, 2012
@ Bewia:

Yet this is what is observed, and it has been accepted in peer review. Where is the physics that reject the proposed model of acoustic waves, and how does it accord with these observations?

And FYI the Michelson-Morley experiment has not been "misinterpreted" but is a test for the accepted general relativity and thus the standard cosmology.

@ 10thman:

If "mathematical band-aids" are so common, how come you can't cite *one* example?

Science is very successful, hence there is no basic problem.

@ Jitterbewegung:

When hearing hoof beats, think horses not zebras. It is convective movements.
GSwift7
1 / 5 (1) Jul 24, 2012
When hearing hoof beats, think horses not zebras. It is convective movements


True. Anyone suggesting that there isn't convection doesn't understand what convection is. 1) we know there's gravity in the sun. 2) we know there are density differences in the sun from temperature differences. >> therefore there must be convection. The question now is why do the accoustic observations above appear to show such slow convection? Is this a problem with the manner of the observations? As usual, when something new challenges large portions of existing theory, caution is the best course of thought. I suggest waiting for responses from other experts.
Michael Mozina
1 / 5 (2) Jul 26, 2012
Ha, an electronic universe crackpot describing 'mindless' parroting. You can accept or reject solar physics, but accepting it is a thoughtful act.


Rejecting a solar model is likewise a thoughtful act, and empirical physics isn't a 'crackpot' idea.

It must hurt an EU-pot that the plasma convection is a lot less powerful than earlier thought.


Not at all! Convection is a "by-product" in Birkeland's cathode solar model, convection is not an "energy source" to explain solar flares. If anything, his model is *significantly strengthened* by this finding, whereas mainstream solar theory bites the dust if this data holds up.

@ baudrunner:

"the Iron Mantle Theory".

Another 'theory' that hasn't passed peer review? And how do you propose to test your theory? Where is the physics in "acoustic oscillations echo back" as opposed to a solar physics model, and how does it accord with these observations?


The model has been peer reviewed and makes many testable predictions.
Bewia
1 / 5 (1) Jul 26, 2012
The model has been peer reviewed and makes many testable predictions.
Could you plz provide some link to peer-review and predictions of that theory? The Google/Bing search returns nothing for keyword search "Iron Mantle Theory" - which is suspicious by itself.
Michael Mozina
1 / 5 (1) Jul 26, 2012
The model has been peer reviewed and makes many testable predictions.
Could you plz provide some link to peer-review and predictions of that theory? The Google/Bing search returns nothing for keyword search "Iron Mantle Theory" - which is suspicious by itself.


Sure, I'd be happy to do that for you:

http://www.ingent...00001007
http://cdsweb.cer...9509.pdf
http://www.thesur...blog.htm

The prediction of large amount of Ne 4 ions in the photosphere is one of the very unique predictions of the iron sun/cathode sun listed on my website.
Bewia
3.7 / 5 (3) Jul 26, 2012
..the sun has a solid, electrically conductive, ferrite surface, just below the observable photosphere... It is rigid.. It is being dynamically reshaped and eroded by continual electrical arcing between magnetically polarized points along the surface... The sun's inner fission reactions act as a battery, releasing free protons and electrons, while the surface acts as a giant conductor. As these streams of electrons reach the surface, they ionize ferrite at the surface, pushing it into the silicon layer of the photosphere, which in turn insulates the electrical flow to create giant electrical arcs between surface features. The neon layer acts as a giant discharge lamp, emitting and adsorbing electrons.
Sorry, this cannot work physically. The ferrite decomposes well bellow the temperature at the surface of Sun, not to say about its interior.
Michael Mozina
1 / 5 (2) Jul 26, 2012
Sorry, this cannot work physically. The ferrite decomposes well bellow the temperature at the surface of Sun, not to say about its interior.


Sure it can. Just as the corona is thinner and hotter than the chromosphere and the chromosphere is thinner and hotter than the photosphere, the silicon plasma layer under the neon photosphere is cooler and more dense than the predominantly neon photosphere. The silicon plasma layer is also much thicker in terms of total depth than any other layer. It's much cooler (less than 1200K) where it meets up with the solid surface than where it meets up with the base of the neon photosphere. Whereas the photosphere is only about 500KM thick, the silicon plasma layer is over 4000KM thick.

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