Flux Ropes in the Solar Wind

[CharlesChandler]

The actual paper.
The flux tube texture of the solar wind.
http://www.readcube.com/articles/10.1029/2007JA012684

More comments: this paper is turning out to be pretty much the nitty-gritty anatomy of a Birkeland current. It shows that in the "flux tubes", the B-field in the center of the tube is parallel to the tube, while the B-field in the wall of the tube is perpendicular, which is what we would expect for electrons spiraling around the longitudinal axis -- the strongest field is generated in the center by the rotation of the electrons around the axis, while they also have a secondary spin that generates a perpendicular field that is only apparent in the tube wall (since superposition overpowers it in the center). And all of the parameters that they measured varied with respect to the position within the tube (center vs. wall), including particle velocity, ion entropy density, proton/electron ratio, electron temperature, and field-aligned electron flux. The fact that the flux tubes begin with the same radius as granules allows me to trace them all of the way from the surface of the Sun, through the helmet streamers, into the heliospheric current sheet, and then into the aurora.

The next step will be to figure out what the heck happens to the current after the aurora. It's the same current flowing into both the north and the south poles, so it isn't a feed-thru current. And you can't just pump current into a capacitor indefinitely -- sooner or later, it shorts out. So if there is a current flowing into the Earth's environment, if not the Earth itself, it has to come back out somewhere, right?

One theory is that the current flows into the Earth on the day side, and then across the surface at the poles as the Pederson current, and then back out into space on the night side.

http://upload.wikimedia.org/wikipedia/e ... ystems.png

But then I'd expect for the aurora to be concentrated into shafts on the day & night sides, not distributed in a ring going all of the way around. Also, the image above is showing two currents on each side (day/night): one flowing into the Earth, and the other flowing out. Yet the aurora only has one concentric ring of discharge. So I really don't understand that model, and I'm wondering if it was just a hastily rationalized answer for the same questions that I'm asking now, and which really doesn't match up with the fine-grain detail.

Has anybody studied the aurora, and if so, what am I'm missing here?

[CharlesChandler]

OK, here's my take on the aurora.

Though there are definitely Birkeland currents getting directed toward the poles by the geomagnetic field, the luminosity of those currents stops abruptly about 80 km above the surface, and neither visually nor with instrumentation can currents be detected that extend all of the way to the ground. This can only mean that the currents terminate in the atmosphere.

How could this be?

Given that at 1 AU, the electrons in the solar wind are still traveling faster than the +ions, and given that the solar wind gets accelerated toward the Earth, the force doing the accelerating has to prefer electrons over +ions. And indeed, though the Earth is net neutral, the surface is negative and the atmosphere is positive. Thus a negative test charge out in space will see a net attraction to the Earth, because it's closer to the positive atmosphere than to the negative surface, and the electric force obeys the inverse square law, so the attraction to the positive atmosphere is more forceful than the repulsion from the surface. So it makes sense that a negative charge stream is accelerated toward the Earth along the magnetic field lines.

Ah, but electrons aren't going to get accelerated all of the way to the negative Earth -- somewhere in there, the E-field flips, and electrons are repelled from the negative surface. To see where this happens, let's start at the surface. Since it's negatively charged, +ions in the atmosphere will be pulled down. So that's a downward conventional current. But with altitude, the field density decreases, for two reasons: 1) getting further away from the surface, the inverse square law mandates a weaker field, and 2) a positive test charge will still be attracted to the negative surface, but it will also be repelled from other +ions between it and the surface. This continues, until the E-field relaxes down to nothing at all, which is at about 80 km above the surface. Above 80 km, the E-field flips, and a positive test charge is more repelled by other positive charges than it is attracted to the negative surface. The corollary is that above 80 km, a negative test charge is pulled downward, but below 80 km, it is pushed upward. So the Birkeland currents are accelerated until they get to 80 km above the surface, and then they are decelerated. When the electrons slow down, they become candidates for recombination, which produces the photons, especially along the base of the aurora.

This suggests that the "Pederson current", as well as the "auroral electrojets", aren't doing much, if anything at all. If the analysis above is correct, the current doesn't continue on into the Earth, nor does it move from the day to the night night, or anything like that. Rather, it terminates in the atmosphere, at roughly 80 km above the surface.

Here we should note that Birkeland's terella experiments succeeded in creating discharges that formed a ring around the magnetic poles, but they failed to get the discharges to stop short of the terella. This is because he created an E-field between the terella and a plate overhead, so of course the current continued all of the way to the sphere. Getting the current to stop short of the sphere could only have been accomplished with charged double-layers such as I described above, where the E-field flips mid-air, but which he didn't test.

Then the only question is: what replenishes the supply of +ions in the atmosphere, to keep pulling the Birkeland currents out of the HCS and down into the aurora? The CFDL model answers that the surface of the Earth is negative for its own internal reasons (i.e., the topmost layer just happened to be negative), and that the atmospheric charge is induced. So below 80 km, any molecule that gets photoionized will yield a +ion getting pulled toward the Earth, and a free electron getting pushed out into space.

[jacmac]

I think something similar is happening on the sun. What if there was a very much larger current, and it came in radially from all directions, would not the whole planet glow. Or much larger yet, would not the planet become a sun.

That is what I am trying to say in a clumsy way in my just now posted: New Solar Model/Capacitor

Jack

[CharlesChandler]

What if there was a very much larger current, and it came in radially from all directions, would not the whole planet glow.

I'll check out the other thread, but yes, this "could be" a way for planets to grow, assuming that both electrons and +ions are in the solar wind. If the charges haven't recombined yet, they're subject to being directed toward a planet by its magnetic field -- otherwise the solar wind would just pass them by. But once captured, the recombined particles could then contribute to the mass of the planet. I don't know what the rate would be, such as the mass of the particles coming in through the Earth's aurora. So I don't know if this would satisfy the requirements for any of the "growing Earth" hypotheses.

[celeste]

What if there was a very much larger current, and it came in radially from all directions, would not the whole planet glow.

I'll check out the other thread, but yes, this "could be" a way for planets to grow, assuming that both electrons and +ions are in the solar wind. If the charges haven't recombined yet, they're subject to being directed toward a planet by its magnetic field -- otherwise the solar wind would just pass them by. But once captured, the recombined particles could then contribute to the mass of the planet. I don't know what the rate would be, such as the mass of the particles coming in through the Earth's aurora. So I don't know if this would satisfy the requirements for any of the "growing Earth" hypotheses.

Charles, Jacmac said glow not grow, but that leads to an important point. I don't think combining electrons and ions to form neutral mass is what is interesting, (or what happens). Start simply,and consider the opposite case. What if we had a neutral mass just shy of causing compressive ionization, and had more neutral matter falling in on it by gravitational means. May that not lead to compressive ionization? That is a sudden onset of radial electric current, isn't it? So a planet may GROW in mass, and begin to GLOW, at the same time?

What caught my eye was the comment by EyeOn-W-ANeedToKnow here
http://www.thunderbolts.info/wp/forum/phpB ... 251#p99285
"While they're at it, I wouldn't mind them explaining how ONE sphere gets to gravitationally "push" highly selective materials..." Yet that is what happens isn't it? If gravity can cause segregation of charge by ionization of neutral material, that does lead to gravity pushing out selective material according to how hard it is to ionize, correct?

This leads to a point I missed, but will no doubt be important. What happens if we have a mass of VARIOUS neutral materials collapsing. If we have neutral material that is hard to segregate by gravitational means, it remains part of the collapsing neutral material. But that increasing gravitational field, increases the radius at which the more easily ionized material, gets pulled apart into charge segregated components.


This is where we have to go back to the mainstream model (a star collapses to a neutron star,or with more mass, a black hole), and start completely over. If we have a neutral mass large enough to cause charge segregation, and add mass, we grow the radius of the stable charge segregated layers? We don't collapse everything to a single point? In effect, gravity does lead to repulsive forces?

[Maol]

What if there was a very much larger current, and it came in radially from all directions, would not the whole planet glow.

I'll check out the other thread, but yes, this "could be" a way for planets to grow, assuming that both electrons and +ions are in the solar wind. If the charges haven't recombined yet, they're subject to being directed toward a planet by its magnetic field -- otherwise the solar wind would just pass them by. But once captured, the recombined particles could then contribute to the mass of the planet. I don't know what the rate would be, such as the mass of the particles coming in through the Earth's aurora. So I don't know if this would satisfy the requirements for any of the "growing Earth" hypotheses.

This is how Earth accretes water (and other mass) from the solar wind. Some loose electrons, some protons and oxygen ions, gather them together in the magnetosphere and in the shadow of the planet where they can cool below ionization potential so their opposite charges can attract and poof, H2O. This replaces the H2O that evaporates to space. If it were not for this process, Earth would be as dry as Mars.

[CharlesChandler]

Jacmac said glow not grow...

Oops.

What if we had a neutral mass just shy of causing compressive ionization, and had more neutral matter falling in on it by gravitational means. May that not lead to compressive ionization? That is a sudden onset of radial electric current, isn't it? So a planet may GROW in mass, and begin to GLOW, at the same time?

Yes, particle deposition increases the mass, which increases the electron degeneracy pressure, which separates charges into double-layers. But I'm not sure that the deposition would be sudden enough to drive a current robust enough to make the planet glow. On another thread I mentioned that sudden changes of pressure at depth due to earthquakes drive electric currents, sufficient to generate corona discharges. But those aren't sustained glows.

If gravity can cause segregation of charge by ionization of neutral material, that does lead to gravity pushing out selective material according to how hard it is to ionize, correct?

Yes. Matter that is tough to ionize will resist getting compacted by gravity, and therefore will "float" on top of other matter that is easily compacted, and therefore gets a lot more dense, and settles to the bottom.

But that increasing gravitational field, increases the radius at which the more easily ionized material, gets pulled apart into charge segregated components.

Yes.

If we have a neutral mass large enough to cause charge segregation, and add mass, we grow the radius of the stable charge segregated layers? We don't collapse everything to a single point? In effect, gravity does lead to repulsive forces?

Exactly. Once the charges are separated, with +ions toward the center, and excess electrons toward the surface, the electrostatic repulsion between +ions prevents the gravitational collapse. And while gravity increases with the amount of mass present, so does the Coulomb force, which is 39 orders of magnitude more powerful. Gravity is no match for the electric force, and no, there is no such thing as gravitational collapse into neutronium. If it were not for the Coulomb barrier, the Universe would be a very different place. For one thing, nuclear fusion would be easy. But we wouldn't care, because the entire Universe would be just one big clump of neutronium.

Note that as you mentioned earlier, there are liable to be a variety of elements inside a star, and compounds inside planets, each with different ionization potentials. So there can be as many charged double-layers as there are distinctly different potentials. My model of the Sun has 5 layers of charge, so it isn't just +ions in the core, and -ions above that. It all depends on the gravitational loading and ionization potential for whatever happens to be at that depth.

http://qdl.scs-inc.us/2ndParty/Images/C ... rs_wbg.png

I'm still counting the layers inside the Earth. It seems that the crust is negatively charged, while the mantle is positively charged, and arc discharges across the boundary when the pressure changes create the Moho, which I believe to be a supercritical fluid. That's charge separation with a lot less mass than inside the Sun, but the heavy elements and compounds inside the Earth are easier to ionize.

This is how Earth accretes water (and other mass) from the solar wind. Some loose electrons, some protons and oxygen ions, gather them together in the magnetosphere and in the shadow of the planet where they can cool below ionization potential so their opposite charges can attract and poof, H2O. This replaces the H2O that evaporates to space. If it were not for this process, Earth would be as dry as Mars.

I totally agree. Carbon and nitrogen are also abundant (next to hydrogen and helium), so it's no surprise that CO2 and N2 are common in planetary atmospheres. All three (C, N, & O) have been confirmed as fusion by-products in solar flares. So we don't need no dirty snowball comets to fill up the terrestrial bathtub -- we can get it all from the solar wind.

[upriver]

Here is the mainstream view of the earth system..

[CharlesChandler]

Here is the mainstream view of the earth system...

I don't know about most of that stuff, but I haven't seen anything to the effect that there is an outward current, as in the diagram. So I'll keep a look-out for that in the literature. So much reading... Anyway, what I've seen so far is that the inbound current is mainly electrons, and they get accelerated up to 60,000 km/s (1/5 the speed of light), in order to have the energy to produce the observed radiation. With such a robust accelerating force, it's hard to imagine what might also be accelerating electrons in the opposite direction -- the same force doesn't accelerate the same particles in opposite directions.

The full write-up that I'm doing is here: Heliosphere.

[Maol]

You don't suppose the electrons could be accelerating away from each other?

[Michael Mozina]

https://news.yahoo.com/hot-stuff-toxic- ... 31468.html

FYI, I thought this was an interesting article that describes the physical processes above volcanic activity on Earth. I'd expect that a significant heat source like the sun would create such "twisting" structures all the time in it's atmosphere.

[jacmac]

If neutral matter were moving into the corona of the sun(or any other very "hot" environment) would not the 2/3 million degrees break up any elements into its basic electrons and protons ? Is this called thermal ionization ?

[CharlesChandler]

You don't suppose the electrons could be accelerating away from each other?

Where, in the corona, or in the interplanetary flux tubes, and/or in the auroral Birkeland currents?

Anyway, electrostatic repulsion can certainly accelerate like-charged particles, but it tends to do so in a radial pattern, not in a filament. So I think that there has to be both a push (from electrostatic repulsion of like charges) and a pull (from attraction to opposite charges), to get z-pinched Birkeland currents.

If neutral matter were moving into the corona of the sun(or any other very "hot" environment) would not the 2/3 million degrees break up any elements into its basic electrons and protons? Is this called thermal ionization ?

Yes. But what neutral matter are you talking about?

BTW, I solved another mystery with regards to the aurora. It is well known that the aurora is more brilliant when the polarity of the HCS is "southward", meaning that it is opposite from the Earth's field at the magnetopause, and the same as the field that passes through the center of the Earth. The HCS normally has a horizontal polarity, but it becomes vertical if the magnetic field lines close on each other. For example, in this image...

http://qdl.scs-inc.us/2ndParty/Images/C ... CS_wbg.png

...if the outwardly-projecting lines on top of the HCS were to close on the inwardly-projecting lines on the bottom, the closing segment would be vertical, and in Earthly terminology, we'd call this a southerly orientation. (See http://www.atoptics.co.uk/highsky/auror2.htm for some diagrams of this.)

So why would this have a bearing on the brilliance of the aurora? It shouldn't, because equal quantities of each polarity emanate from the Sun. And both the aurora borealis and the aurora australis are mirror images of each other, with the same luminosity, and the same general form at any given point in time.

Then I realized that if a southerly field was projecting outward from the northern hemisphere of the Sun, it can feed directly into the northern hemisphere of the Earth, as in the following image.

http://qdl.scs-inc.us/2ndParty/Images/C ... th_wbg.png

But what happens when the Sun's polarity flips, and a northerly field projects outward from the northern hemisphere of the Sun? Then, when the HCS comes under the influence of the Earth's magnetic field, the flux tubes have to cross each other, to get to the opposite hemisphere of the Earth, as in the lower panel of this image:

http://qdl.scs-inc.us/2ndParty/Images/C ... ty_wbg.png

Data from ACE verify that "flux tubes" do, in fact, weave their way past each other, differentiating themselves on the basis of magnetic polarity, as in this image from the paper that Brant cited:

Borovsky, J. E., 2008: Flux tube texture of the solar wind: Strands of the magnetic carpet at 1 AU? Journal of Geophysical Research: Space Physics (1978–2012), 113 (A8)

http://qdl.scs-inc.us/2ndParty/Images/C ... angled.png

It isn't hard to imagine why energy would be lost in this weaving process, resulting in less distinct auroras.

I hope that you folks are having at least half as much fun as I'm having with this. What we're seeing here is the full elucidation of the Sun~Earth connection, from Birkeland currents emerging out of solar granules, forming up into helmet streamers, which feed into the heliospheric current sheet, which gets intercepted by the Earth's magnetic field and guided down into the aurora, where the charges finally recombine. The closer we look, the more accurate the picture, and all with well-established principles of EM.

[celeste]

BTW, I solved another mystery with regards to the aurora. It is well known that the aurora is more brilliant when the polarity of the HCS is "southward", meaning that it is opposite from the Earth's field at the magnetopause, and the same as the field that passes through the center of the Earth. The HCS normally has a horizontal polarity, but it becomes vertical if the magnetic field lines close on each other. For example, in this image...

http://qdl.scs-inc.us/2ndParty/Images/C ... CS_wbg.png

...if the outwardly-projecting lines on top of the HCS were to close on the inwardly-projecting lines on the bottom, the closing segment would be vertical, and in Earthly terminology, we'd call this a southerly orientation. (See http://www.atoptics.co.uk/highsky/auror2.htm for some diagrams of this.)

So why would this have a bearing on the brilliance of the aurora? It shouldn't, because equal quantities of each polarity emanate from the Sun. And both the aurora borealis and the aurora australis are mirror images of each other, with the same luminosity, and the same general form at any given point in time.

Then I realized that if a southerly field was projecting outward from the northern hemisphere of the Sun, it can feed directly into the northern hemisphere of the Earth, as in the following image.

http://qdl.scs-inc.us/2ndParty/Images/C ... th_wbg.png

But what happens when the Sun's polarity flips, and a northerly field projects outward from the northern hemisphere of the Sun? Then, when the HCS comes under the influence of the Earth's magnetic field, the flux tubes have to cross each other, to get to the opposite hemisphere of the Earth, as in the lower panel of this image:

http://qdl.scs-inc.us/2ndParty/Images/C ... ty_wbg.png

Data from ACE verify that "flux tubes" do, in fact, weave their way past each other, differentiating themselves on the basis of magnetic polarity, as in this image from the paper that Brant cited:

Borovsky, J. E., 2008: Flux tube texture of the solar wind: Strands of the magnetic carpet at 1 AU? Journal of Geophysical Research: Space Physics (1978–2012), 113 (A8)

http://qdl.scs-inc.us/2ndParty/Images/C ... angled.png

It isn't hard to imagine why energy would be lost in this weaving process, resulting in less distinct auroras.

Charles, I think there is still an effect we are missing. Let me start simply. Let's say we have a sphere, where gravity caused charge segregation. Now let that sphere rotate in an external magnetic field,aligned more or less with the sphere's spin axis. Notice that one direction of that background magnetic field, leads to positive charges drifting towards the spin axis,and negative charges drifting outward. Switch the polarity of the background field, and our rotating sphere has negative charges drifting inward,and positive charges drifting outward. Even if the background magnetic field is weak, having our charged double layer sphere rotating in that field must either enhance or detract from the gravitational segregation of charge.
The electric field across any double layers on Earth, are not just functions of Earth's gravity, but on how the solar magnetic field is oriented compared to Earth's spin axis? Is that right?

[CharlesChandler]

The electric field across any double layers on Earth, are not just functions of Earth's gravity, but on how the solar magnetic field is oriented compared to Earth's spin axis? Is that right?

I'm not sure that the Sun's magnetic field (i.e., the field in the heliospheric current sheet) affects the Earth in a substantial way. The Earth's magnetic field is 10−5 teslas, while the HCS's (out at 1 AU) is 10−9 teslas. So the Earth's field is easily strong enough to overpower the HCS, and direct it into the aurora. Fluctuations in the HCS can also cause geomagnetic storms, and induce currents in long wires and in long pipelines. It's possible that the HCS does other things, but it's very weak compared to the geomagnetic field, and extremely weak compared to gravitational force at the surface.