From NASA JPL: Solar flares – they’re big and they’re fast. They can knock out a satellite or create a beautiful aurora. And the jury is still out on what causes these explosions.
Flares, and the related coronal mass ejection, shoot energy, radiation, and magnetic fields out into space that can harm satellites or humans in space. Current observations aren’t precise enough to determine whether the eruptions are driven by energy surging through the sun’s surface, or by the sudden release of energy that has slowly accumulated in the atmosphere.
This aurora over Valkeakoski, Finland on September 15, 2000 resulted from the September 12 coronal mass ejection featured in the video above. › Download video Credit: Tom Eklund
Now, a new way of looking at old data has changed all that, but the results have created more mystery: There isn’t enough energy passing through the surface during the eruption to drive the explosion.
“In some sense, the idea that energy from below triggers the eruption is the easiest explanation – like a geyser,” says Peter Schuck, a physicist who studies space weather at NASA’s Goddard Space Flight Center in Greenbelt, Md. “But if the idea doesn’t agree with what’s observed, then it’s wrong. End of story.”
Schuck’s research indicates that, instead, the trigger occurs in the sun’s atmosphere. “Our result shows that observations are more consistent with a slow accumulation of energy in the atmosphere,” Schuck said, “and then a sudden explosion triggered from above, more like lightning.”
Schuck studies coronal mass ejections, or CMEs, and solar flares at the place where theory and observation overlap. His latest work on CMEs appeared in the Astrophysical Journal on May 1. Schuck constructed a way to test CME and flare observations in order to limit which group of hypotheses fit the data, even when there’s not enough evidence to conclusively pick a single theory.
In the case of CMEs, the data is limited to distant movies captured by spacecraft such as the Solar and Heliospheric Observatory (SOHO). These movies show that CMEs begin as a gigantic arch, some 50 times larger than Earth, with each of its feet planted on the sun’s surface, or “photosphere.”
Two broad camps of theories have been developed to explain these so-called coronal loops. “The energy is built up by either a twisting motion below the surface or the release of magnetic energy in the solar atmosphere,” says Haimin Wang, a physicist at the New Jersey Institute of Technology, whose work focuses on the characteristics of the photosphere before and during solar ejections.
Either way, the energy originally comes from the surface. The question is simply whether it surges through directly before the appearance of the coronal loop or oozes up slowly over time, storing up in the atmosphere until released in a massive explosion of light, plasma, magnetic fields and high energy particles.
Distinguishing between the two options based solely on a distant movie isn’t easy. Imagine trying to figure out what powers a car when all you’ve got to go on is a movie of a highway. Worse, that movie isn’t from above, so you might easily determine the direction and speed of those cars, but from head-on or a side view where you’re not even sure of the angle.
If, however, you can infer the speed of the car, you could at the very least figure out how much energy it has and, in turn, rule out any power source that didn’t jibe with what you saw.
Schuck has done exactly that. “I developed a way to infer magnetic field motion, and therefore energy amounts, from the velocities we observe in the photosphere,” he says.
Imagine the cars again. If the cars were coming directly toward you, you could measure the wavelength of the headlights and by determining how strongly they’d been shifted by the Doppler effect (that same wave-changing effect that causes sirens to sound higher as they come toward you and lower as they move away) you could measure the car’s speed.
Schuck used similar, head-on Doppler measurements to find the velocity of solar material on the surface of the sun. This material moves perpendicular to the magnetic field at the base of the coronal loop — the crux of what Schuck is trying to understand. He can convert those initial velocities of the sun’s surface into information about the motion and energy of the magnetic field. This analysis may not spit out an exact number for the energy, but it does give a precise, accurate range of energy possibilities.
And so, for the first time, one can look at images of the sun and set firm limits on the maximum energy at a given spot – at least if the material was moving directly towards the camera to provide an accurate Doppler measurement.
The next step applies the analysis to an actual coronal mass ejection. Schuck looked at the data from a CME on September 12, 2000. This was an M-class ejection — meaning it was fairly intense, but one step below the strongest X-class — that moved directly towards Earth. Conveniently, this was also a well-studied flare, so other scientists had already examined SOHO images to measure the path, speed, and energy of the CME. This information, in turn, implies how much energy would have come through the photosphere at the start of the process had it indeed initiated from below.
The results were dramatic. The SOHO images showed the photosphere moving at speeds 10,000 times less slowly than would have been expected if it were directly triggering the eruption. “The velocity you’d need to see on the photosphere would be a thousand kilometers per second,” says Shuck. “Not only are these speeds easily detected but they would be greater than the standard measurement range of the instrument. You’d see really weird stuff in the data readouts.”
There is always the slim chance that somehow the instruments didn’t catch the extreme motion, but given how large the velocities would have had to be, Schuck thinks this is unlikely.
This still leaves a variety of theories on just how the energy is stored and what triggers its release in the atmosphere. Distinguishing between those theories will require more detailed data—something scientists hope NASA’s Solar Dynamics Observatory, launched in February 2010 will be able to provide.
Unlike previous missions, SDO will be able to directly measure the energy in the photosphere – as opposed to Schuck’s present method of inferring that energy from velocity measurements — and it will do so with 20 times the resolution of the data on which Schuck based his current work. Such information will help narrow down what triggers a CME or solar flare even more precisely.
“Now we just need some really big CMEs to work with,” says Schuck.
h/t to Dr. Leif Svalgaard
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tallbloke says:
November 25, 2010 at 11:19 pm
Yes, I want to Work this one through as the null hypothesis. I’m interested to discover if any effort has gone into modeling the early solar system to recreate this process of EM coupling which transferred the energy from the sun to the planets, to see if that process develops a resonance amplified rhythm.
This has been modeled many times. One would not expect [and therefore not model or find] any resonance effects as the transfer takes place so early that the planets are not even formed yet [it is the gas they condense from that is being pushed out]. To call this ‘EM’ is really a bad idea. Electromagnetic is usually [and reasonably] used for photon effects. The coupling was magnetic. Magnetic field lines have tension in them: try to pull two magnets apart and feel the tugging.
Would low windspeed have increased the EM entrainment and angular momentum transfer in the early solar system?
The main agent was the magnetic field. The speed is not so important and tend to vary a lot less: the plasma just has to escape the Sun and the escape speed depends largely on gravity, thus the mass of the Sun.
tallbloke says:
November 25, 2010 at 11:19 pm
to see if that process develops a resonance amplified rhythm.
Once the planets were formed some migrated inwards and some outwards. This is actually quite complicated business:
http://en.wikipedia.org/wiki/Formation_and_evolution_of_the_Solar_System#Planetary_migration
During their migration they can pass points were they are in resonance and once there the migration might stop. Again, this has no influence on the Sun or solar activity as the planets then already were too far away for tidal interactions.
tallbloke says:
November 25, 2010 at 11:19 pm
to see if that process develops a resonance amplified rhythm.
This paper may be of interest: http://arxiv.org/abs/1011.5226
Yes, less variation would be expected if the planets had not yet formed. OK thanks Leif, that gives me a bit to go on for now.
brant:
Thank you for providing the UCLA paper and the UCLA photo gallery. I have read and viewed both and appreciate the authors’ discussion.
The paper employs the study of magnetic fields to, in part, derive a resolution of the charged particle current flows. As the authors contend resolution of the current flow is important for understanding the larger system. This fits well with what I’ve been pointing out: Mapping the movement of charged particles is critical for understanding the dynamics when two bodies of plasma collide. brant, as you point out, the authors conducted the experiment where bodies of magnetized plasma were collided within a background magnetized plasma. This is a laboratory experiment which offers a rough approximation of space plasma dynamics.
Space plasma environments tend to be “rivers within larger rivers of plasma”. Or distinct, structured flows of plasma within larger flows of plasma. In numerous instances, these structured flows of plasma take the form of magnetic flux tubes.
And colliding bodies of plasma are ubiquitous in space plasma environments.
According to Alfven, there are two basic approaches to understanding the dynamics of plasma environments: From the observation & measurement of magnetic fields or from the explicit observation & measurement of charged particles currents, both neutral plasma currents, such as they exist, and segregated currents of charged particles, electric currents.
As Alfven noted, each approach has value, but there are some processes or dynamics which the study of magnetic fields, alone, can not fully resolve, while it is Alfven’s contention that an explicit identification & resolution of charged particle current flows is necessary before these processes and dynamics can be fully resolved.
brant, wouldn’t it be more informative if all the images of magnetic fields in the UCLA photo gallery, also included detailed resolution of the charged particle flows, too?
In essence, that’s what the authors of the paper are attempting to do.
Alfven simply contends there is a direct way to determine the currents, through electrical circuit theory — yes, Hannes Alfven considered himself an electrical engineer, although, he taught physics and was a professor of electromagnetic theory and electrical measurements. It’s an electrical engineer’s business to map electrical current flows and understand all the instabilities, discontinuities, and dynamics along the current flow. Double layers are often a dynamic along the current flow.
One of the processes or dynamics which can be fully resolved by mapping current flows is what happens at the “X” point often discussed in “magnetic reconnection” papers.
The “X” point discussed in “magnetic reconnection” papers is where charged particles’ electric force and magnetic fields cross, or interact, just as Hannes Alfven described in his empirical laboratory work on Electric Double Layers and, is central to the acceleration of charged particles in both sets of papers, Electric Double Layers and “magnetic reconnection”, respectively, I provided previously in the comment thread.
The interaction of magnetic fields and charged particles’ electric force results in the formation of arrays of oppositely charged particles, thus, an electric field which causes charged particle acceleration with electrons being jetted out one current channel and ions being jetted out the opposite direction in a current channel.
It is the interaction of charged particles and magnetic force which animates this “X” point’s dynamic processes.
The study of magnetic fields indirectly accounts for current flow by way of curl, this, Alfven contends, is imprecise, rather Alfven asserts that current flow can be directly accounted for and this will provide higher resolution and understanding of the overall system in all its facets.
Isn’t that what everybody is striving for, no matter what side the question they approach from?
James F. Evans says:
November 26, 2010 at 10:33 am
The study of magnetic fields indirectly accounts for current flow by way of curl, this, Alfven contends, is imprecise, rather Alfven asserts that current flow can be directly accounted for and this will provide higher resolution and understanding of the overall system in all its facets.
The current flows as dictated by the magnetic field. This is the precise behavior of space plasmas.
Isn’t that what everybody is striving for, no matter what side the question they approach from?
I don’t think so. The EU crew has an agenda and that dictates what they strive for.
You have not yet provided the list of authors and papers that explicitly state that reconnection is a failed paradigm, and you have not yet [repeated] reminded us of what powers the Sun. The answer to that exposes the agenda, so show us that you don’t have any.
Dr. Svalgaard wrote: “The current flows as dictated by the magnetic field. This is the precise behavior of space plasmas.”
The issue is the mathematical treatment of “i”, current, and correctly identifying particle behaviour, when describing electromagnetic phenomena via mathematical equations focussed on magnetic field “B”.
According to Alfven, Cosmic Plasma, Electric Currents in Space Plasmas, II.1. Dualism in Physics, the magnetic centered mathematical equation “gives a poor and often misleading representation of the particle phenomena.”
http://books.google.dk/books?id=ZjwoGlIxvLUC&pg=PA11&dq=alfven+cosmic+plasma&source=gbs_toc_r&cad=3#v=onepage&q=alfven%20cosmic%20plasma&f=false
See the above link for a more complete explanation for why explicit mathematical equations focussed on “i”, current, is more precise for resovling the particle behavior within a plasma system. (first page of the link)
Dr. Svalgaard wrote: “You have not yet provided the list of authors and papers that explicitly state that reconnection is a failed paradigm…”
First, as you have already noted, scientists in these two opposing schools tend not to discuss the other school’s theories in their own published works. Rather, they focus on aspects of their own approach to the question at hand.
But Hannes Alfven did address this issue in his NASA presentation:
“I sincerely hope that the increased interest in the study of double layers — which is fatal to this pseudoscience [“magnetic reconnection”] — will change the situation. Whenever we find a double layer (or any other E does not equal zero) we hammer a nail into the coffin of the ‘merging’ pseudo-science.”
http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19870013880_1987013880.pdf
(Interested readers should link and read Alfven’s introductory presenation.)
So, according to Alfven, implicitly, every scientist who studies double layers states that reconnection is a failed paradigm. (See lists of scientists who study double layers in the above link and in the Wikipedia entry for Double layers (plasma)).
Dr. Svalgaard wrote: “…you have not yet [repeated] reminded us of what powers the Sun.”
I’ve answered your question twice, already: I don’t know.
What I do know is that there are unexplained anomalies.
But considering how many direct questions you have ignored, are you sure you aren’t the one with an agenda in this discussion.
Dr. Svalgaard acknowledges the existence of double layers.
Dr. Svalgaard stated: ““Double layers indeed exist”
But what does that mean?
The following questions try to put Dr. Svalgaard’s acknowledgment in proper context:
Evans (November 25, 2010 at 9:58 am) asked, “Dr. Svalgaard, do double layers exist in space? And, if so, under what circumstances do double layers exist in space? What parts of space do double layers exist in? Are there limitations on what parts of space double layers exist in? And, what is the result of the presence of double layers in space?”
I never got an anwer from Dr. Svalgaard — is that because he has an agenda?
Dr. Svalgaard, you are refusing to compare & contrast the two sets of papers I presented, which stand for the proposition that Double Layers and so-called “magnetic reconnection” are actually the same physical phenomena, is that because you have an agenda?
My agenda is to understand the physical processes & dynamics of the world around me. In that quest I will follow the facts & evidence to wherever it leads me.
I will not ignore facts or evidence because of some pre-existing dogma which has been eclipsed by new observations & measurements.
James F. Evans says:
November 26, 2010 at 1:20 pm
the magnetic centered mathematical equation “gives a poor and often misleading representation of the particle phenomena.”
Modern treatment of the problem included both the magnetic, electric, and particle aspects. There are no ‘magnetic centered equations’.
First, as you have already noted, scientists in these two opposing schools tend not to discuss the other school’s theories in their own published works. Rather, they focus on aspects of their own approach to the question at hand.
There are no modern scientists in the EDL-school. Show us a list of them and some of their publications from the last ten years.
Dr. Svalgaard wrote: “…you have not yet [repeated] reminded us of what powers the Sun.” I’ve answered your question twice, already: I don’t know.
Or you will not admit. So, you acknowledge that the presentation of this in for ex. http://www.bibliotecapleyades.net/electric_universe/electric_sun02.htm#The Electric Glow of the Sun if faulty [or not convincing to you].
Evans (November 25, 2010 at 9:58 am) asked, “Dr. Svalgaard, do double layers exist in space? And, if so, under what circumstances do double layers exist in space? What parts of space do double layers exist in? Are there limitations on what parts of space double layers exist in? And, what is the result of the presence of double layers in space?” I never got an anwer from Dr. Svalgaard — is that because he has an agenda?
As I have said many times, magnetic reconnection can create electric fields and currents and lead to separation of charges into transient current sheets, which at rare times resemble EDLs.
I will not ignore facts or evidence because of some pre-existing dogma which has been eclipsed by new observations & measurements.
Show us some of those new observations which are contradicting the successful paradigm of magnetic reconnection.
James F. Evans says:
November 26, 2010 at 1:20 pm
Evans (November 25, 2010 at 9:58 am) asked, “Dr. Svalgaard, do double layers exist in space? And, if so, under what circumstances do double layers exist in space?…
Let me explain a bit more what the difference between magnetic reconnection and electric double layers is. First some general information about EDLs:
An EDL is very thin. About 10 Debye lengths. Some typical thicknesses:
In the lab: 0.1 cm. In the ionosphere 1 cm. In the magnetosphere 1 km. In the solar wind 100 m. An EDL cannot form in many places. The Bohm Criterion for formation of an EDL is that the electric field vanishes at the boundaries of the EDL.
Let us consider the case of the ionosphere [where we have good in situ data] during time of an active aurora. The aurora is the result of a ‘substorm’ which is triggered by magnetic reconnection far out in the tail [typically 50,000 km out]. The resulting Birkeland currents create an EDL in the ionosphere at 100-300 km height. Thus at a very different place and after the reconnection event. On the day-side where the solar wind directly connects to the Earth’s magnetic field there is steady reconnection with no explosive effects and no EDLs. These processes are discussed in several papers, e.g. http://www.leif.org/EOS/2006JA012007.pdf which you are cordially invited to study.
An older [but still good] discussion of what an EDL is and when it can form is given by Raadu and Rasmussen in http://www.leif.org/EOS/1988ApSS-144.pdf [which BTW is a paper dedicated to Hannes Alfven on occasion of his 80th birthday]. Note, that there is no mention of magnetic fields at all in the paper. This is because EDLs are created in current carrying plasmas [and have nothing to do as such with any magnetic field]. So the next question comes up: how does one create a current in a cosmical plasma? The answer is, of course, by moving a neutral plasma into a magnetic field, or by pressing together [by plasma movements] magnetic fields of opposite polarity resulting in magnetic reconnection.
On the same occasion a paper by deJager discussed the merits/problems of the Alfven-Carlquist idea of ‘exploding’ EDLs as causes of solar flares. At the time [1987] it was not conclusive which way the answer would tilt. A big negative for the exploding EDL model was the time scale involved: flares happened must faster than the EDLs would allow. Since then, this problem has resulted in the reconnection mechanism becoming the dominant paradigm [last man standing]. There was also the problem of how to drive the currents in the first place. Reconnection elegantly takes take of that. The exploding EDL theory is by now quite dead.
Leif Svalgaard says:
November 26, 2010 at 6:28 pm
I forgot one important place:
Some typical thicknesses:
In the lab: 0.1 cm. In the ionosphere 1 cm. In the magnetosphere 1 km. In the solar wind 100 m. In the solar corona above an active region [where flares and CMEs come from] 1 cm. The general formula for the thickness T is T = 700 meter * sqrt (temperature in K / density in particles per cubic meter).
James F. Evans says:
November 26, 2010 at 1:20 pm
scientists in these two opposing schools tend not to discuss the other school’s theories in their own published works.
Even at Alfven’s old institute, the researchers have embraced the magnetic reconnection paradigm: http://www.leif.org/EOS/2010GL044611.pdf
“[2] Magnetic reconnection is a major mechanism in space and astrophysical plasmas for converting energy stored in magnetic fields into particle kinetic energy and for exchange of mass, energy and momentum between differently magnetized plasma regions. In near‐earth space many properties of reconnection can be studied by spacecraft [Paschmann, 2008]. We use observations at the magnetopause by the Cluster spacecraft with multi‐scale separation. The point of this investigation is to study both the properties of the magnetopause, including plasma composition, and the fundamentals of reconnection, including the origin of the electric fields accelerating particles.”
Needless to say, there is no mention of Double Layers [as they don’t form out there at the magnetopause].
Leif Svalgaard says:
November 26, 2010 at 6:28 pm
Note, that there is no mention of magnetic fields at all in the paper. This is because EDLs are created in current carrying plasmas [and have nothing to do as such with any magnetic field]. So the next question comes up: how does one create a current in a cosmical plasma? The answer is, of course, by moving a neutral plasma into a magnetic field, or by pressing together [by plasma movements] magnetic fields of opposite polarity resulting in magnetic reconnection.
Leif, forgive the naieve qustion. How do plasma fields push magnetic fields about unless they are themselves carrying magnetic fields?
Thanks.
Dr. Svalgaard stated: “Note, that there is no mention of magnetic fields at all in the [Raadu and Rasmussen double layer] paper.”
Dr. Svalgaard goes on to state: “This is because EDLs are created in current carrying plasmas [and have nothing to do as such with any magnetic field]. ”
Both statements are false.
From the Raadu paper presented by Dr. Svalgaard:
“Double layers are of interest in astrophsics as a direct means of accelerating particles (Alfven, 1981, 1986). They can sustain a local region of parallel electric field leading to the magnetohydrodynamic relaxation of a large-scale magnetic field. The globally stored magnetic energy is then released both as accelerated particles and in mass motions set up by the untwisting motions of magnetized plasma (Raadu, 1984).
http://www.leif.org/EOS/1988ApSS-144.pdf
Dr. Svalgaard claimed: “…[double layers] have nothing to do as such with any magnetic field…”
Dr. Svalgaard, with misrepresentations such as yours…readers should treat your statements caution.
From the UCLA photo gallery:
Caption for first image: “Three dimensional field lines taken from a volumetric data set in an experiment in which two laser produced plasmas collide. Data was acquired at 30,000 locations in a 3D volume in the LAPD device. Shown are the magnetic fields due to Alfven wave currents. The two Carbon targets that the lpp plasmas originate at are seen in the background. The “sparkles” are the induced electric field calculated from -dA/dt. Note that the induced field is largest in the reconnection region at the center of the image. The data is acquired 5 us after the targets are struck and 6.56 meters and 65.6 cm away. There is a background He plasma (n = 2X10^12 cm-3, B0z (not shown) = 600G)”
To highlight: “The “sparkles” are the induced electric field calculated from -dA/dt.”
http://plasma.physics.ucla.edu/pages/gallery.html
And a close up on the image:
http://plasma.physics.ucla.edu/images/gallery/BEz656-t512.jpg
The outbreaking of electric fields, mini- parallel electric fields, is due to the charged particles’ electric force interacting with the magnetic field. The maximum electric field breakout is in regions of highest magnetic field stress and maximum charged particle density.
The higher the charged density & magnetic field stress, the greater the formation of electric fields (arrayed mini-parallel electric fields).
It’s important to examine the UCLA image of the breakout of electric fields in relation to magnetic fields — the two forces are inter-related as Maxwell’s equations amply demonstrate.
One of the processes or dynamics which can be fully resolved by mapping current flows is what happens at the “X” point often discussed in the relevant scientific literature.
The interaction of magnetic fields and charged particles’ electric force results in the formation of arrays of oppositely charged particles, thus, an electric field which causes charged particle acceleration with electrons being jetted out one current channel and ions being jetted out the opposite direction in a current channel.
It is the interaction of charged particles & magnetic force which animates this “X” point’s dynamic processes.
Every charged particle in a plasma physical state has an electric force as denoted with a negative or positive charge, the Coulomb force.
The electric force of charged particles interacts with the magnetic force resulting in electric fields, which, thus, then accelerate charged particles.
Charged particle density is a significant determinant of the magnetic fields and resultant formation of electric fields.
The process is a positive self-reinforcing feedback loop. This suggests the potential of rapid build-up of electric potential drop, voltage, and upon discharge, rapid dispersal of energy as expressed by charged particle kinetic acceleration and radiation.
This is all part of the Electric Double Layer analysis & interpretation:
“A double layer is a structure in a plasma and consists of two parallel layers with opposite electrical charge. The sheets of charge cause a strong electric field and a correspondingly sharp change in voltage (electrical potential) across the double layer. Ions and electrons which enter the double layer are accelerated, decelerated, or reflected by the electric field. In general, double layers (which may be curved rather than flat) separate regions of plasma with quite different characteristics. Double layers are found in a wide variety of plasmas, from discharge tubes to space plasmas to the Birkeland currents supplying the Earth’s aurora, and are especially common in current-carrying plasmas.”
http://en.wikipedia.org/wiki/Double_layer_(plasma)
Here is the other double layer paper presented by Dr. Svalgaard:
Large parallel electric fields, currents, and density cavities in
dispersive Alfve´n waves above the aurora
C. C. Chaston,1 A. J. Hull,1 J. W. Bonnell,1 C. W. Carlson,1 R. E. Ergun,2
R. J. Strangeway,3 and J. P. McFadden1
Received 7 August 2006; revised 22 November 2006; accepted 15 January 2007; published 24 May 2007
http://www.leif.org/EOS/2006JA012007.pdf.
It’s a fairly recent 2007 paper with a number of author scientists — the double layer approach, based on circuit theory of charged particles is healthy and advancing.
By the way, magnetic fields are also discussed in this paper, as well.
The integration of the magnetic field and electric field and charged particle’ electric force analysis & interpretation and the predictability such particle and energy behavior is robust with quantitative mathematical formalism fully expressed in the Double Layer approach.
Compare & contrast the physical dynamics of exploding double layers as observed & measured in the laboratory and predicted for the formation and propagation of CME’s with the actual observed & measured formation and propagation of CME’s.
Once CME’s are resolved, then the comparison between the two processes should be simple enough.
My prediction: The movement of charged particles, the magnetic fields & electric fields will be the same for the predicted exploding double layer model and the actual observations & measurements of the formation & propagation of CME’s.
If my prediction turns out to be right:
Then what is your opinion going to be, Dr. Svalgaard?
Satellite in situ probes will provide empirical observation & measurement.
That’s where the rubber meets the road and I look forward to the data as it is reported.
tallbloke says:
November 27, 2010 at 12:06 pm
Leif, forgive the naive qustion. How do plasma fields push magnetic fields about unless they are themselves carrying magnetic fields?
Normally if you shoot neutral, non-magnetic plasma into a magnetic field, the plasma would flow around the field [called diamagnetism], but the exclusion is not perfect because the charges at the boundary will begin to gyrate around the external magnetic field [ http://en.wikipedia.org/wiki/Guiding_center ]. So can penetrate bit for bit, especially if the the kinetic energy of the plasma is high. There is more on page 3 and 4 of http://www.leif.org/research/suipr699.pdf for the specific case of the Earth’s magnetosphere.
James F. Evans says:
November 27, 2010 at 12:54 pm
Satellite in situ probes will provide empirical observation & measurement.
That’s where the rubber meets the road and I look forward to the data as it is reported.
I think you are confusing two things: Do double layers exist? is magnetic reconnection the same as exploding double layers?
The answer to the first is obvious. Of course, they exist. They have been observed and there is good theory about them. I know of no scientists who doubt their existence.
The answer to the second is also obvious. Of course magnetic reconnection is not the same as a double layers. I know of no scientist who doubt that. Find me some who do.
BTW, how thick do you think a double layer would be in the solar atmosphere where a flare or CME happens?
James F. Evans says:
November 27, 2010 at 12:54 pm
My prediction: The movement of charged particles, the magnetic fields & electric fields will be the same for the predicted exploding double layer model and the actual observations & measurements of the formation & propagation of CME’s.
And what, specifically are those predictions? How would you know that you would be right? E.g. how thick do you think those exploding double layers would be?