Solar Wind as an electric current

[iantresman]

Is it fair to describe the Solar Wind as an electric current, after all, it is a movement of charge particles?

Regards,
Ian Tresman

[tusenfem]

Is it fair to describe the Solar Wind as an electric current, after all, it is a movement of charge particles?

Regards,
Ian Tresman

I don't think so, because as far as I know the solar wind is neutral, which would mean equal amounts of positive and negative moving at the same speed, ergo no current

[Nereid]

Is it fair to describe the Solar Wind as an electric current, after all, it is a movement of charge particles?

Regards,
Ian Tresman
How would you go about determining that it is (or isn't)?

In more detail: what - in as much detail as you can - would be the observations (or experiments) that you could perform (even if only in principle) that would provide you good data that could help you reach even a tentative conclusion?

[iantresman]

In more detail: what - in as much detail as you can - would be the observations (or experiments) that you could perform (even if only in principle) that would provide you good data that could help you reach even a tentative conclusion?

That's a good question. And having read the following two explanations, I'm not sure the answer is that easy:
Electric Current (a definition) (http://www.google.co.uk/search?hl=en&q=%22electric+current%22+electron+pro tons&btnG=Google+Search&meta=)
Which way does the Electricity really flow? (http://www.amasci.com/amateur/elecdir.html)

Regards,
Ian Tresman[/quote]

[PatKelley]

Ian, I know what I'd be fishing for here; and that's falsifiability.

Is there a test you can propose that would work in one manner under current (no pun intended) understandings of the solar wind, but would work differently under the solar-wind-as-current model?

SWAC would have _____ at _____ given element _________.
Current theory would not.

[Mosheh Thezion]

the solar wind carries a Pos charge, it is well known and it is high.

the wind could not be considered an electric current, since it is not electrons giving off an inductive field, but is instead a large current of positively ionized atoms and ionizing radiation, from uv. to protons and anti-electrons(positrons).
there maybe electrons and nuetrons, but the overall charge is POS, thus a lack of electrons generally.
so.. it may be considered a current of positive ions, but since it doesnt follow any specifc path, it would seem.. "wind", is the best word.
-MT

[tusenfem]

the solar wind carries a Pos charge, it is well known and it is high.

Care to elaborate on this with some references?

the wind could not be considered an electric current, since it is not electrons giving off an inductive field, but is instead a large current of positively ionized atoms and ionizing radiation, from uv. to protons and anti-electrons(positrons).
there maybe electrons and nuetrons, but the overall charge is POS, thus a lack of electrons generally.
so.. it may be considered a current of positive ions, but since it doesnt follow any specifc path, it would seem.. "wind", is the best word.
-MT

this does not make sense, the PU/EM theories assume (I hope) that the electrodynamics as set up by Maxwell is still valid. If there would be this high positive charge flowing outward (radially) then at some point the sun would become so negatively charged that the wind would stop, or more likely, the electrons will move along with the ions.
A quick look in "Introduction to Stellar Winds" by Lamers and Cassinelli (two very good solar physicist) does not give any info of the solar wind to be charged. It is a plasma and plasmas tend to be (quasi-)neutral.

[iantresman]

Just to clarify, I'm not particularly trying to get an "electric universe" angle on whether the Solar Wind is an electric current. Just whether it is considered to be so.

I think the answer is yes, the Solar Wind is an electric current, that can supply kinetic energy, but not supply an electromotive force (EMF).

Regards,
Ian Tresman

[Jens]

No, I think normally the solar wind is not considered to be a current, because the the number of positive and negative ions are thought to be equal. So there's no net charge.

I think the question is whether that is really true. How would we know whether the number of protons and electrons in the solar wind is equivalent? It should be testable, and I presume that the reason people conclude it isn't charged it because this has been tested. But it might just be an assumption.

The thing, though, is that one would presume that if only electrons are given out, for example, then eventually the charge would get positive and the electrons would be pulled back in. Unless there is some process that keeps producing a charge, i.e. electrons are coming in from another dimension or something like that. But they you get into unknown physics.

But if you can show that the solar wind is charged, I'd like to hear about it.

[tusenfem]

Just to clarify, I'm not particularly trying to get an "electric universe" angle on whether the Solar Wind is an electric current. Just whether it is considered to be so.

I think the answer is yes, the Solar Wind is an electric current, that can supply kinetic energy, but not supply an electromotive force (EMF).

Regards,
Ian Tresman

How can the solar wind be an electric current when the plasma is neutral and ions and electrons move in the same direction (i.e. away from the sun)?
I think you can better compare it with the "current" of a river, which indeed has a lot of kinetic energy. e.g. 350 km/s with density of ~10 protons per cubic centimeter.

[czeslaw]

I think, you miss something. A wind on the Earth is a movement of particles , which are in electric equilibrium. Every proton has its own electron just around.
The solar wind as a plasma is a movement of particles tend to reach an equilibrium. The proton hasn’t an electron around, they are seeking each other all the time.

A plasma is neutral as whole but electrons and protons move separately, that way there is a magnetic current and energy is carried too.

An alternating current is neutral as whole system, the electrons move forth and back relatively to protons. The energy of the alternating current depends on the voltage and amount of the free electrons. The direction of the electrons is not important.

What is the energy of the plasma ?
The amount of free electrons has their temperature and we may count out the voltage too. U=v^2m/2e .
We can separate electrons from protons in a magnetic field – in normal wind is it not possible.
The radius of the electron is different as of the proton r =mv/eB and the frequency is f =eB/2pi m.
So then, the solar wind might be a cloud moving very fast in the magnetic field with very high oscillate electric current inside.

[tusenfem]

I think, you miss something. A wind on the Earth is a movement of particles , which are in electric equilibrium. Every proton has its own electron just around.
The solar wind as a plasma is a movement of particles tend to reach an equilibrium. The proton hasn’t an electron around, they are seeking each other all the time.

I guess you could look at it that way if you really want. The fact is that the temperature of the particles (electrons and ions) is so high that the stable orbit for the electron at 13.6 eV cannot be entered. The electrons just have too much energy and fly away. The plasma is a whole system, which is in equilibrium (in the restrframe of the plasma) and (quasi-)neutral. I write quasi here, full knowing that this might be misinterpreted, but on small scales there may be slight discrepancies.

A plasma is neutral as whole but electrons and protons move separately, that way there is a magnetic current and energy is carried too.

The electrons and protons move at the same speed, a neutral cloud of plasma passes by the Earth and there is no electric current, let alone a magnetic current.

An alternating current is neutral as whole system, the electrons move forth and back relatively to protons. The energy of the alternating current depends on the voltage and amount of the free electrons. The direction of the electrons is not important.

That makes it rather difficult to light your desklamp, if the direction of the electron is not important. I guess you think here about an electric wire. In space plasma's there are basically only DC currents, unless you want to regard plasma oscillations at the plasma frequency an AC current.

What is the energy of the plasma ?
The amount of free electrons has their temperature and we may count out the voltage too. U=v^2m/2e .
We can separate electrons from protons in a magnetic field – in normal wind is it not possible.
The radius of the electron is different as of the proton r =mv/eB and the frequency is f =eB/2pi m.
So then, the solar wind might be a cloud moving very fast in the magnetic field with very high oscillate electric current inside.

Well, put in numbers and tell us how very high this current is, and look up in a plasma physics book or in "Classical Electrodynamics" by Jackson, if this happens.

[czeslaw]

There is no net electric current (direct current) of course, there are only micro oscillations much more frequent then in our fluorescent lamp.
But, if fluorescent lamp do not shine without electric current, then we can’t see an aurora without electric current too.
A direct current is different then alternating current but both of them are electric currents.

[czeslaw]

I have to laugh. When I did compare a plasma with a hurricane wind it was bad, but if you compare a plasma of solar wind with an earthly wind it is right.

[tusenfem]

There is no net electric current (direct current) of course, there are only micro oscillations much more frequent then in our fluorescent lamp.
But, if fluorescent lamp do not shine without electric current, then we can’t see an aurora without electric current too.
A direct current is different then alternating current but both of them are electric currents.

The currents that create the aurora are not currents flowing in the solar wind, but are created by accelerated particles in the Earth's magnetosphere, for example, when a substorm occurs in the magnetotail.

[czeslaw]

Of course, I didn't write the Earth's aurora is created by currents in the solar wind. The solar wind is neutral as whole, but beautifully interact with Eart's magnetic field.

[Mosheh Thezion]

the solar wind..... is not nuetral, since it's cheif component is the same material that makes up the suns corona cloud...

and what is that material???? POS-pions.. positrons.
being constantly and steadily expelled from the sun...?
and why??? because the sun has a POS core.

http://img267.imageshack.us/img267/2796/solar1ic.th.jpg (http://img267.imageshack.us/my.php?image=solar1ic.jpg)
-MT

also.. it is a fact that if you connect a conductor to the earth, and attach it to the bottom plate of a capacitor, and attach the top plate to a wire.. that as we extend the wire up into the sky, the measurable voltage which exists in the air, rises about 50v peer foot or meter, i forget.

so much so, that if we could but reach the upper atmoshphere, we could charge our capacitor to literally millions of volts, over and over again, and get free energy in vast amounts...

but doing so.. does one thing.. it brings electrons from earth.. to the upper atmoshpere.. and they don't come back.

i believe that lightning is involved with this natural process of depletion of electrons, with the help of the mysterious sprites.

all of which suggest, that what we call ground, is actually negatively charged.

-MT

[Karl]

the solar wind..... is not nuetral, since it's cheif component is the same material that makes up the suns corona cloud...

and what is that material???? POS-pions.. positrons.
being constantly and steadily expelled from the sun...?
and why??? because the sun has a POS core.


Well, positron are ocasionally measured in the sun's corona during large solar flares.

High-Resolution Measurement of the Solar Positron-Electron Annhilation Line (http://sprg.ssl.berkeley.edu/adminstuff/webpubs/2003_ajl_L85.pdf)

But they are not there all the time, if they were they'd be easy to spot.

(edit to fix grammar)

[Mosheh Thezion]

the solar wind..... is not nuetral, since it's cheif component is the same material that makes up the suns corona cloud...

and what is that material???? POS-pions.. positrons.
being constantly and steadily expelled from the sun...?
and why??? because the sun has a POS core.


Well, positron are ocasionally measured in the sun's corona during large solar flares.

High-Resolution Measurement of the Solar Positron-Electron Annhilation Line (http://sprg.ssl.berkeley.edu/adminstuff/webpubs/2003_ajl_L85.pdf)


But if they are not there all the time, if they were they'd be easy to spot.

then what prey tell is the corona cloud compossed of?

-MT

[Karl]

http://solar-center.stanford.edu/FAQ/Qsolwindcomp.html

The solar wind is a collection of streams of energetic particles that originate on the Sun. You can think of the particles of the solar wind as nothing less than the solar corona itself.[Noyes] This is because the distant corona expands outwards due to not enough restraining force from gravity, or from the pressure of the interstellar gas, to confine the distant corona. The solar wind escapes through the coronal holes at supersonic speeds. As the outer corona disperses, it must be replaced by gases welling up from below (lower corona).

The composition of the solar wind is a mixture of materials found in the solar plasma, composed of ionized hydrogen (electrons and protons) with an 8% component of helium (alpha particles) and trace amounts of heavy ions and atomic nuclei: C, N, O, Ne, Mg, Si, S, and Fe ripped apart by heating of the Sun's outer atmosphere, that is, the corona.

SOHO also identified traces of some elements for the first time such as P, Ti, Cr and Ni and an assortment of solar wind isotopes identified for the first time: Fe 54 and 56; Ni 58,60,62 [Galvin].

Note that although the solar wind is electrically balanced, the solar wind consists almost exclusively of charged particles (stripped away nuclei from atoms) and is an excellent electrical conductor. These electrically conducting particles is technically known as a plasma, so it may be misleading to think of the solar wind as like Earth "winds".

(Edit to emphasize point)

[PatKelley]

Shockingly enough, a copper wire is also an electrical conductor. Is this proof that it carries an electrical current? It only says that it can.

There is a small leap to make, that would be measuring actual current rather than saying it could exist. If it's real and it's there, it should have an observable effect. Absent that, it's just potential.

[The Bad Astronomer]

Mosheh is completely wrong. The solar wind is neutral overall. There is a website attached to this bulletin board (http://www.badastronomy.com/bad/misc/mccanney/solarwind.html) (with links to real data).

[Jens]

Mosheh is completely wrong. The solar wind is neutral overall. There is a website attached to this bulletin board (http://www.badastronomy.com/bad/misc/mccanney/solarwind.html) (with links to real data).

This is a quote from one of those links. It's only a paragraph, so I hope it's OK to quote it.

The solar wind is approximately 95% protons or H+ ions (a Hydrogen atom which has lost one electron), 4% alpha particles or He+2 ions (a Helium atom which has lost two electrons) and 1% minor ions (Carbon, Nitrogen, Oxygen, Neon, Magnesium, Silicon and Iron are the most abundant). . . . Scientists assume that on the broad scale, there are no neutral particles or negative ions in the solar wind. The plasma that makes up the solar wind is either a positive ion or a free electron. Also, the solar wind is electrically neutral - it contains an equal numbers of positive and negative charges.

This seems confusing to me. On one hand, it's saying that there are no negative ions. But then it says that the "plasma that makes up the solar wind" has free electrons. And that the solar wind is electrically neutral. How is the solar wind neutral if it is 95% H+, 4% He+2 and 1% minor ions?

[Van Rijn]

The free electrons' negative charge balances things. The net charge is neutral.

[Jens]

I guess what's difficult to understand is the distinction between the "solar wind" and the "plasma of the solar wind." Are there two distinct things? I.e., is there a solar wind, which does not contain electrons, and then something else, which is at the same place as the solar wind, but isn't the solar wind, and which contains electrons?

[01101001]

This seems confusing to me. On one hand, it's saying that there are no negative ions. But then it says that the "plasma that makes up the solar wind" has free electrons. And that the solar wind is electrically neutral. How is the solar wind neutral if it is 95% H+, 4% He+2 and 1% minor ions?

I took the composition as being by mass. Protons and neutrons are heavy compared to electrons.

With the solar wind being basically the same composition as its source, the sun, it is electrically neutral, and is 99.9+% protons and neutrons.

[Carl_Smith]

Mosheh is completely wrong. The solar wind is neutral overall. There is a website attached to this bulletin board (http://www.badastronomy.com/bad/misc/mccanney/solarwind.html) (with links to real data).

One of the links in the page linked to above has this:

The solar wind is a very rarefied plasma: When it reaches the Earth, one finds an average of only 10 protons per cubic centimetre. Therefore the particles in the solar wind rarely collide. Electrons and ions cannot practically neutralize each other. That means that there is a direct connection between the movement of charged particles and the electric currents streaming in interplanetary space. These electric currents are connected to the magnetic field in the solar wind. In this way the magnetic field tells us a lot about the composition and the flow of the solar wind!

Source: http://www.oma.be/BIRA-IASB/Public/Research/SolWind/InterPlanSpace.en.html

Now, at risk of putting my foot in my mouth yet again, this appears to me to indicate there are electric currents in the Solar Wind, and at least in principle it should be possible to make reasonable magnitude estimates if enough solar magnetic field and particle density measurements are available.

[Jens]

This seems confusing to me. On one hand, it's saying that there are no negative ions. But then it says that the "plasma that makes up the solar wind" has free electrons. And that the solar wind is electrically neutral. How is the solar wind neutral if it is 95% H+, 4% He+2 and 1% minor ions?

I took the composition as being by mass. Protons and neutrons are heavy compared to electrons.

With the solar wind being basically the same composition as its source, the sun, it is electrically neutral, and is 99.9+% protons and neutrons.

At first, I was thinking the same thing, that it was mass. But one of the sentences in the passage I quoted reads:

Scientists assume that on the broad scale, there are no neutral particles or negative ions in the solar wind.

So it seems they're saying that there are no electrons, not that the electrons are light and so can be ignored from the mass.

[Mosheh Thezion]

Mosheh is completely wrong. The solar wind is neutral overall. There is a website attached to this bulletin board (http://www.badastronomy.com/bad/misc/mccanney/solarwind.html) (with links to real data).

i would be willing to accept that the any two points in space in the wind... as if we could attach an insulated conductor to any two points in the wind, from center sun and out.. and or from the left side of the sun to the right side.. that indeed the potential we would read across our meter in the center would probubly be zero.


but.. IS it not true that the solar wind charges the upper atmoshpere Pos relative to the earth.. which is then... in a relative sense.. negative.

now.. sir.. in all your wisdom.. is that not true?

-MT

[Van Rijn]

Scientists assume that on the broad scale, there are no neutral particles or negative ions in the solar wind.

So it seems they're saying that there are no electrons, not that the electrons
are light and so can be ignored from the mass.

Huhm? No. Electrons aren't ions, but are elementary particles. As you quoted earlier:

The plasma that makes up the solar wind is either a positive ion or a free electron. Also, the solar wind is electrically neutral - it contains an equal numbers of positive and negative charges.

(bolding added) Mass is a separate issue from charge, of course.

[Jens]

Huhm? No. Electrons aren't ions, but are elementary particles. As you quoted earlier:


Ah well, stupid assumption on my part. I assumed that because a hydrogen atom without an electron (i.e., just a proton) is considered a positive ion, then a hydrogen atom without a proton (i.e., just an electron) would be considered a negative ion. I now realize that for it to be a negative ion, it would have to be a proton with, say, two electrons. So I guess it has to have a nucleus to be considered an ion. I'm sure I learned that in high school, many years ago. :oops:

[tusenfem]

Now, at risk of putting my foot in my mouth yet again, this appears to me to indicate there are electric currents in the Solar Wind, and at least in principle it should be possible to make reasonable magnitude estimates if enough solar magnetic field and particle density measurements are available.

There is such a thing as the heliospheric current sheet in the solar system, which can be compared to the current sheet in the Earth's magnetotail, which takes care of the field reversal from Earthward in the northern hemispher to tailward in the southern hemisphere of the tai.
The latest paper on this topic is by Roberts, Keiter and Goldstein, Melvyn L., titled "Origin and dynamics of the heliospheric streamer belt and current sheet" (Journal of Geophysical Research, Volume 110, Issue A6, CiteID A06102, 2005).
However, this is not a radially outstreaming current, as envisioned in the OP.

[czeslaw]

A solar wind is like e,p,e,p,e,p,e,p where e-electron, p-proton. As whole is it neutral, of course.

But there are distances between electron and proton till 1 mm. If a speed of solar wind is 1000 km/s , the charge oscillation is then 10^9 Hz. It may cause an alternating current in the conductor due to magnetic field.

Today 9.Aug.2005 the solar wind is carrying a magnetic field total B=6,1 nT according to NASA values.
There isn’t a direct current like in a battery from one point to another, but there is an alternating current carrying a magnetic field and energy we can use. It is not possible for a wind on the Earth.

The Earth’s wind has its pressure and solar wind has its pressure (today –0,5 nPa). The solar wind is carrying a magnetic field B=6,1 nT, but Earth’s wind is almost B=0.

You have to decide, what about a current you want to write, a direct current or an alternating current.

[tusenfem]

A solar wind is like e,p,e,p,e,p,e,p where e-electron, p-proton. As whole is it neutral, of course.

sure if you want to look at it in that way.

But there are distances between electron and proton till 1 mm. If a speed of solar wind is 1000 km/s , the charge oscillation is then 10^9 Hz. It may cause an alternating current in the conductor due to magnetic field.

The density near earth of the solar wind plasma is say 10 per cc, so interparticle separation on the order of mm. But HOW do you turn a density and a velocity into a freuquency???? I guess you just say that if L is the interparticle separation, say L = 1 mm and the velocity of the plasma is v = 1000 km/s you can just say: f = v / L. TRY AGAIN!!! although dimensionally is SEEMS okay, physically it is rubbish.

I'll just snip the last part, because that does not make sense either.

[czeslaw]

Today’s density of the solar wind plasma is 14 particles/cm^3 - Dials are updated every 5 minutes with data averaged over last 15 minutes. http://www.sel.noaa.gov/SWN/sw_dials.html .

I wrote an example if the plasma is in equilibrium , the particles (+) and (-) move in distance (it might be more then 1 mm). If electron will be close to nucleus (proton) they created a neutral atom and such a wind can not carry a magnetic field. The plasma do not carry a net charge then but it can carry an electric energy and do a work like the electric current does although it is not a direct electric current.

[tusenfem]

Today’s density of the solar wind plasma is 14 particles/cm^3 - Dials are updated every 5 minutes with data averaged over last 15 minutes. http://www.sel.noaa.gov/SWN/sw_dials.html .

I wrote an example if the plasma is in equilibrium , the particles (+) and (-) move in distance (it might be more then 1 mm). If electron will be close to nucleus (proton) they created a neutral atom and such a wind can not carry a magnetic field. The plasma do not carry a net charge then but it can carry an electric energy and do a work like the electric current does although it is not a direct electric current.

czeslaw: READ A BOOK ON PLASMA PHYSICS!!!!!!
Have you cared to look at the energy of the plasma components? Do you think that the (for simplicity) the protons and electrons can recombine? Do you think that a neutral plasma cannot have a magnetic field? What do you understand under a neutral plasma? What about a frozen in field? What is your electric energy? Can a neutral plasma not carry a current? What work does a current do, and how can your electric energy do the same work as a current would?
Just some questions for tuesday afternoon.
YEAH! the space shuttle landed safely in California!

edited to add one more question.

[Mosheh Thezion]

Does the solar wind, charge the upper atmosphere POS+...

yes it does, so relative to us, humans on earth, at ground.. the solar wind is positive.. because it surtainly isnt negative.

of course photons play a big part in the ionization of the upper atmosphere.. but they also play a major role in the solar wind.

-MT

[The Bad Astronomer]

Mosheh, do you have a source for the claim that the upper atmosphere is positively charged from the solar wind? And one that gives details? I have never heard this before.

[iantresman]

Mosheh, do you have a source for the claim that the upper atmosphere is positively charged from the solar wind? And one that gives details? I have never heard this before.

I wonder whether the Earth's fair weather electric field is evidence of this, measured at about 100 volts per metre with the Earth defined as "ground". More at:

http://science.nasa.gov/newhome/headlines/essd15jun99_1.htm

Regards,
Ian Tresman

[czeslaw]

We write about different currents, I think, and there is a misunderstanding.
A neutral plasma do not carry a charge and you write, there is no electric current, Yes, there is no direct current. Why is there a magnetic field then? Does the air on the Earth carry a magnetic field ? No. Plasma can? Yes, because there are charge micro oscilations, something like in alternating current. A direct current and alternating current are different phenomenons.

A perfect plasma of the school is neutral and each proton has its electron around, but it is theoreticaly only. Normal plasma are the proton and electrons moving very fast, interacting with photons of the Background radiation, thermal radiation, magnetic fields, gravity fields etc. The electrons permamently tends to equilibrium with protons. There could be no net charge but there is charge oscillation and plasma move along magnetic field. If plasma would be neutral like air it would not interact with magnetic field, as the air do. The electrons are not bound to protons as in an atom. They move freely very fast seeking an equilibrium. That way plasma do carry a magnetic field.

Assuming that each plasma is frozen to its own magnetic field, and that cross-field diffusion is absent, we conclude that the two plasmas will not mix, but, instead, that a thin boundary layer will form between them, separating the two plasmas and their respective magnetic fields. In equilibrium, the location of the boundary layer will be determined by pressure balance. Since, in general, the frozen fields on either side of the boundary will have differing strengths, and orientations tangential to the boundary, the layer must also constitute a current sheet. Thus, flux freezing leads inevitably to the prediction that in plasma systems space becomes divided into separate cells, wholly containing the plasma and magnetic field from individual sources, and separated from each other by thin current sheets.

If the plasma dynamics becomes too fast , then resonances occur with the motions of individual particles , which invalidate the MHD equations. Furthermore, effects, such as electron inertia and the Hall effect, which are not taken into account in the MHD equations, become important.
The plasma is tied to magnetic field-lines, it follows that magnetic field-lines embedded in an MHD plasma act rather like mutually repulsive elastic bands.

If we remove a magnetic field , the plasma work like a charged cloud, although is it neutral. Similar work does an alternating current. There is no charge movement but work is done like by direct current.

The solar wind do not carry a direct electric current but it acts like a kind of the alternating electric current.

[Mosheh Thezion]

Mosheh, do you have a source for the claim that the upper atmosphere is positively charged from the solar wind? And one that gives details? I have never heard this before.

well besides.. TESLA..

i quickly found this source.. and while it may not be the best, it does discuss the matter in question.
http://www.auf.asn.au/meteorology/section11.html

quote...
"During fair weather there is an electric potential difference of 250 000 to 500 000 volts between the ionosphere and the Earth’s surface, the surface being negative relative to the ionosphere. This gives rise to the fair weather current which is a steady flow of electrons from the surface at about one microwatt per square metre. "

-MT

[The Bad Astronomer]

That's interesting, and I accept there is a charge separation, with the upper atmosphere being positive. But there is no source for the separation mentioned in that article. I found web pages that say that thunderstorms are the reason for the charge separation, not the solar wind. This makes a lot more sense to me, and also jobes with the solar wind being neutral overall.

[Mosheh Thezion]

That's interesting, and I accept there is a charge separation, with the upper atmosphere being positive. But there is no source for the separation mentioned in that article. I found web pages that say that thunderstorms are the reason for the charge separation, not the solar wind. This makes a lot more sense to me, and also jobes with the solar wind being neutral overall.
well.. the wind itself.. maybe made up of nuetral amounts of electrons and protons... thus neutral..
but when its blasted off the sun... its ionized.. and as it travels to the earth its ionized.. and its the radiation, ie.. light, uv, xrays.. that maintains it that way.
and when all this hits our atmosphere.. it ionizes it.. i.e ripps off electrons from it.. and literally carries them away, on the whole.. planet scale i mean...

this bath of uv and xray light does hit the atmosphere, and is not deflected by the magnetic field.

then its a simple question of whether these electrons fly down, or off into space.....?? i tend to think space.
-MT

[czeslaw]

Theoretically a plasma is neutral but it would be too simple in our reality, I think.

The real solar wind is mixed with a dust, Cosmic Rays, different radiation, magnetic and gravity fields, it is changing with a time according to solar activity.
I do not believe the solar wind is smooth and perfect neutral. There are double layer accelerating heavy protons and light electrons. It is to complicate.
There have to be the parts of space with a different charges.

[tusenfem]

We write about different currents, I think, and there is a misunderstanding.
A current is a current, be it direct or alternating, it still is differential motion between the positive and the negative charges.

A neutral plasma do not carry a charge and you write, there is no electric current, Yes, there is no direct current. Why is there a magnetic field then? Does the air on the Earth carry a magnetic field ? No. Plasma can? Yes, because there are charge micro oscilations, something like in alternating current. A direct current and alternating current are different phenomenons.

A neutral plasma means that there are EQUAL amounts of positive and negative charge. Like in a Tokamak, where we have a neutral plasma, there can be a direct current, or how do you think they heat the plasma to get it to fusion?
A neutral plasma blob can have its own magnetic field, just by having currents flowing in the plasma. A (not perfect) example would be a CME (Coronal Mass Ejection) which has a doughnut like shape.

A perfect plasma of the school is neutral and each proton has its electron around, but it is theoreticaly only. Normal plasma are the proton and electrons moving very fast, interacting with photons of the Background radiation, thermal radiation, magnetic fields, gravity fields etc. The electrons permamently tends to equilibrium with protons. There could be no net charge but there is charge oscillation and plasma move along magnetic field. If plasma would be neutral like air it would not interact with magnetic field, as the air do. The electrons are not bound to protons as in an atom. They move freely very fast seeking an equilibrium. That way plasma do carry a magnetic field.

No, a perfect plasma (of the school??) is neutral, but all the charged particles are on their own little trip. There is no grouping of (to keep it simple) protons and electrons sticking together as a nice married couple. You have to put energy in the first gas, turn it into a plasma, and the kinetic energy of the particles greatly exceeds the electrostatic energy, so there is no recombination.
From your text above, and I quote If plasma would be neutral like air it would not interact with magnetic field, as the air do. it is clear you do not understand what is meant by a neutral plasma.

Assuming that each plasma is frozen to its own magnetic field, and that cross-field diffusion is absent, we conclude that the two plasmas will not mix, but, instead, that a thin boundary layer will form between them, separating the two plasmas and their respective magnetic fields.

Do you think that a "frozen in field" only has to do with two plasmas bordering eachother? Is a "frozen in field" not just a logical consequence of the MHD equations?


I stop here, because if you don't get the basics, there is no use discussing anything more complicate like you want to do in the rest of your message. I give you the following literature list of books I find useful and have in my own little science library:

In increasing complexity
1. Kivelson and Russell, Introduction to Space Physics
2. Marcel Goossens, An Introduction to Plasma Astrophysics and MHD
3. Goedbloed and Poedts, Priniples of Magnetohydrodynamics
4. Baumjohann and Treumann, Basic Space Plasma Physics

[czeslaw]

Because both the electrons and ions are free to move in a plasma, a wide variety of waves can exist in the solar wind. These waves are called plasma waves. Because collisions are extremely rare in the tenuous solar wind, plasma waves play a role similar to collisions in an ordinary gas by scattering particles and providing the dissipation necessary to achieve thermal equilibrium.

Three principal types of plasma waves were detected : (1) the free space electromagnetic mode, (2) the electron plasma oscillation mode, and (3) the ion acoustic mode.

The electron plasma oscillation is an almost purely oscillatory mode in which the electrons vibrate around their equilibrium position while the ions remain at rest. The resulting charge oscillation produces an electric field but no magnetic field. For this reason these waves are sometimes called electrostatic waves.

Because of the large inertia of the ions, the propagation speed of the ion acoustic mode is quite slow, normally much less than the solar wind speed, which is typically about 400 km/sec. As in the case of electron plasma oscillations the ion-acoustic mode is electrostatic, with no magnetic field.

The electron plasma frequency, which is the characteristic frequency of electron plasma oscillations and the low frequency limit of the free space electromagnetic mode, increases from about 20 kHz at the Earth's orbit to several hundred MHz at the solar surface. The ion plasma frequency, which is the upper frequency limit of the ion acoustic mode, varies from about 500 Hz at the Earth's orbit to a few MHz at the solar surface.

It is plasma.

[tusenfem]

<snip>
It is plasma.

And this answers which of my questions???

[czeslaw]

You asked what is the neutral plasma . So, it is as above with its consequences of the oscillating charges.

[tusenfem]

You asked what is the neutral plasma . So, it is as above with its consequences of the oscillating charges.

Sure, I know all that what you so nicely copied from somewhere, I asked you a lot of questions, this does not answer any of them, definitely not if you understand what a neutral plasma is.
What do these plasma modes have to do with your nonsense calculation of a frequency f = v / L? etc. You can copy as much as you like, but the important part is if you understand it.

[czeslaw]

If a conductor moves relative to the oscillating charges, there is an alternating current induced.

[tusenfem]

You're just playing games czeslaw and I am not going to play along anymore. Whenever I say something you just sidestep or come up with something else. You have yet to show that you have any real understanding of plasma physics.

[czeslaw]

I am not a professional physicist like you. I like to hear a klezmer music and discuss about a physics. This ATM Forum is the best for people like me. A sharp discuss with you forces me to study a physics problems better.

A plasma is usually mixed with an equal amount of the protons and electrons and seems to be electrically neutral.
Because of the free electrons and ions and relatively long distances between them we observe the charge oscillations. That is right , I think.

If there is charge oscillation , there is an alternating electric current, which may be induced in a conductor moving through plasma, isn’t it? If you move a conductor in the air there is no electric current at all.

[Gillianren]

I think the problem is that you need to study the subject first, and this is not the place for basic plasma education. (though I'm sure learning a lot.) it is not tusenfem's job to educate you, heaven knows. you must start that process yourself. while you may appreciate the help you're given at it, you've been told, repeatedly, to read a book first, and you're still telling people that the picture of the universe they have is wrong.

let me say this again, in case you've missed it.

I am not a scientist. I have not studied these fields, certainly not in any detail. ergo, I will assume that those who have studied the field know more than I do and not try to overthrow the current worldview.

maybe it's language problems, but you come across like you're trying to teach us about a subject about which you don't know much.

[czeslaw]

Do you think , I am not right ? There are not charge oscillations in a plasma? Doesn't this oscillation induce an alternating current in a moving conductor through this plasma ?

[Karl]

Do you think , I am not right ? There are not charge oscillations in a plasma? Doesn't this oscillation induce an alternating current in a moving conductor through this plasma ?

The conductor does not need to be moving, since the electrons are in motion. I think what you are trying to describe is what is called thermal plasma noise (http://image.gsfc.nasa.gov/publication/document/2002_issautier_etal_02.pdf), which is related to the plasma frequency (http://www.ph.unimelb.edu.au/staffresources/lecdem/ei6.htm).

[czeslaw]

Of course, it is obvious, I think. I do not understand why
tusenfem quarrels with me.
There is a link about plasma, very good and simple:
http://www.nationmaster.com/encyclopedia/Plasma_physics

[The Bad Astronomer]

then its a simple question of whether these electrons fly down, or off into space.....?? i tend to think space.
-MT

Based on what? There is no evidence of this, and lots of evidence against it.

[Nereid]

I do not understand why tusenfem quarrels with me.
I'm not sure I'd call it 'quarrelling', rather (seems to me) giving you some sound advice (learn plasma physics, so that, at the very least, you can ask more meaningful questions).

A particularly good piece of advice (IMHO) was to NOT use questions and answers here in the BA forum as a method for learning (plasma) physics.

If I may add to this excellent advice? posting in the ATM section will likely make your learning even more difficult (if, indeed, you do decide you wish to learn). Why? Because, as the BA says about this section "If you have some idea which goes against commonly-held astronomical theory, then you are welcome to argue it here. [...] People will attack your arguments with glee and fervor here; that's what science and scientists do. If you cannot handle that sort of attack, then maybe you need to rethink your theory, too. Remember: you came here. It's our job to attack new theories. Those that are strong will survive, and may become part of mainstream science. [...]" This kind of environment is not particularly conducive to learning first principles, if - as seems to be the case with your ideas - you are presenting "some idea which goes against commonly-held astronomical theory"

[czeslaw]

Some of you wrote, there is no electric curent in the solar wind. It is like a wind on the Earth or like a water in a river.

I say - there is no direct electric current but there is an ALTERNATING ELECTRIC CURRENT.

According to our discussion it it clear noe, I think.

[iantresman]

I think the problem is that you need to study the subject first, and this is not the place for basic plasma education.
I have to disagree. I think we are all learning, novices and astronmers alike. I think we have all learnt that plasma is deceptively complicated subject, and I'd be very surprised if both sides haven't learnt something (to do with the subject, rather than the perceived ignorance on each side).

I think this subject "whether the Solar Wind is an electric" is a good example. It doesn't seem to have a definitive yes/no answer.

Regards,
Ian Tresman

[01101001]

ALTERNATING ELECTRIC CURRENT

What is its frequency?

[iantresman]

I say - there is no direct electric current but there is an ALTERNATING ELECTRIC CURRENT

"Whether the Solar Wind is an electric current" has become much more complicated than I anticipated. What I have learnt is as follows:

1. Although moving charges (electrons or protons) define an electric current, it is also a vector quantity. So the simply answer is that the NET electric current in a neutral ideal plasma is ZERO because the electrons and protons cancel.

2. However, plasma is not simple, and accept in text books, it is not ideal. We don't get each proton pairing with a specific electron (as we do in a non-ionized gas). As a result, currents may arise.

3. Consequently it is important to specify a frame of reference. So astronomers can talk about the Solar Wind's electron current (in its own frame of reference), or ion current, but which taken together, cancel.

4. There are lots of forces on Solar System ions and protons; they don't just move outward from the Sun in pairs. Anywhere these forces cause the ions and protons to move differently to one another, so that there is net movement of electrons or protons, will cause a current. And this does happen, and are called drifts. For example, the effect of gravity on ions depends on their mass, and as Alfvén suggests, may produce chemical separation, and produce a current.

5. I think I understand what czeslaw means by a plasma having an "alternating current", but I don't think the analogy works. In a circuit with an alternating current, the ions move back and forth, and over the duration of one cycle, have a net motion of zero, but nevertheless, there is a measurable current. I don't think it works with plasmas because there is no obvious frame of reference, which is why plasmas are generally treated statistically, and we have Debye lengths, and quasi-neutrality. But a plasma does have a Scalar Potential and Coulomb Potential, but I haven't figured out what they mean yet.

6. In more detail, George K Parks writes in Physics fo Space Plasmas:
".. Electric and magnetic fields depend on the coordinate frame in which the fields are measured. The fields measured in stationary and moving frames are related by the Lorentz transformation theory of electromagnetic fields. The motional electric field is called convective electric field if the plasma motion does not change the magnetic energy. In this case, the electric field in the plasma frame vanishes and the electric field is perpendicular to the magnetic field. Motional electric fields are ubiquitous in Nature. An electric field will also be induced by the motion of a rotating plasma across a magnetic field. A rotational electric field arises because an electric field will exist in a nearby volume of plasma unless it moves around with the planet or star. In ideal plasmas, the electric field in the rotating frame vanishes and the plasma corotates perfectly with the rotating body. Note that a rotating frame is not an inertial frame of reference and this problem cannot be understood using the results of the special theory of relativity. Instead, one must invoke Einstein's theory of general relativity to study electrodynamics in noninertial frames".

7. David P. Stern who writes the excellent Exploration of the Earth's Magnetosphere (http://www.phy6.org/Education/Intro.html) web site, replied to me as follows:

Your question opens the door to some interesting physics. The proper definition would actually be
"Electric current is the NET rate of charge flow past a given point in an electric circuit".

That is, positive charges moving in one direction contribute the same as negative charges moving in the opposite direction. A flow of equal densities of protons and electrons flowing in the same direction then does not carry any current--the positive contribution and the negative one cancel each other.

It is otherwise in the ring current carried by particles trapped in the Earth's magnetic field--see items (3) and (4) in
http://www.phy6.org/Education/wtrap1.html

By the above definition, the main flow of the solar wind will not carry any electric current. However, subtle effects associated with density variations and bending of magnetic field lines do create currents even in the solar wind. Such currents must be taken into account in space plasmas.

Consider the following situation. Take a sheet of paper and with a pencil draw on it some closed contour--say, a "potato shape." Imagine now that a magnetic field exists, everywhere parallel and pointed OUT of the sheet. Imagine also that those lines inside the "potato" contain plasma of constant density, while space outside it is a vacuum.

By item (1) of the above web files, all trapped ions (viewed from above) circle their field lines CLOCKWISE, while electrons circle counterclockwise. (They may also slide up and down while circling, but we assume new ones then take their place, so that the density does not change).

Draw two touching orbits inside the "potato", for either two electrons or two positive ions. Where they touch, their motions are opposite, so their combined current is ZERO. Mathematically one can show this is a special example of a general case--the currents due to the gyration, anywhere in the interior, always cancel--and they do so for each species separately.

But it isn't true on the boundary! Any gyrating ions whose motion touches the boundary creates there an ion flow which is clockwise, and each electron creates an electron flow which is counterclockwise. Each of the species then contributes a clockwise current around the boundary.

That is a real effect, and is responsible, for instance, for the fact that at the inner edge of the ring current (item (4) above) the current density is actually counterclockwise (viewed from north), opposed to the general ring current carried by the transport of particles.

This weird behavior of the plasma also affects the solar wind. It causes a current sheet around the Sun's equator--one whose direction depends on the polarity of the Sun's global field, which reverses every solar cycle, i.e. every 11 years or so.

Sorry! But than, no one has promised us that nature was simple!

Conclusion

So I guess that to ask "whether the Solar Wind is a current" is poor question, like asking whether the sea is a current; it has currents, but it is not a current.

Regards,
Ian Tresman

[Nereid]

I think the problem is that you need to study the subject first, and this is not the place for basic plasma education.I have to disagree. I think we are all learning, novices and astronmers alike. I think we have all learnt that plasma is deceptively complicated subject, and I'd be very surprised if both sides haven't learnt something (to do with the subject, rather than the perceived ignorance on each side).
There is surely no doubt that learning is taking place.

However, a more pertinent question is, is it particularly effective learning?

That plasmas are tricky beasts and that simple word pictures describing them are full of traps (to paraphrase Ian, with some distortion) is pretty unsurprising; that this thread has little to do with an ATM (and much to do with educating some posters, who seem to have a bent for some of the things they've read on some woowoo sites) may be nice, but it's not what threads in ATM are *for* (in this sense, it resembles more a Questions and Answers (http://www.universetoday.com/forum/index.php?showforum=13) thread in Universe Today).

In terms of the history of the participation of the main posters in this thread, that it's more like a simple FAQ than a gleeful and fervent attack on an ATM idea isn't surprising either - after all, none of the proponents of EU/PU/PC ideas demonstrated even quite elementary understanding of the basic physics behind the ideas they sought to propose (at least, not here in BA). #-o

[fixed typo]

[Karl]

5. I think I understand what czeslaw means by a plasma having an "alternating current", but I don't think the analogy works. In a circuit with an alternating current, the ions move back and forth, and over the duration of one cycle, have a net motion of zero, but nevertheless, there is a measurable current.

I would quibble this point, having a "net motion of zero' implies that there is no net current, but there is energy transfer.

[Mosheh Thezion]

then its a simple question of whether these electrons fly down, or off into space.....?? i tend to think space.
-MT

Based on what? There is no evidence of this, and lots of evidence against it.

well... supossively our planet looses gas molecules all the time.. mostly hydrogen.. which fritters off from the top of the atmosphere.

and if hydrogen can do it.. why not a highly charged electrons which weights 1836 x less.. and with energizes available in the xray level..
-MT

[tusenfem]

That is one BIG post Ian. And a good one if I may say so.
The "quarrel" I have with czeslaw, well no, it is not a quarrel per se, is that I try to keep it simple for starters, and czeslaw want to dive into the deep part of the swimmingpool, before being able to manage in the undeep part (IMHO).
Let us first consider a neutral plasma flowing past the Earth, the solar wind, no direct currents there, so no the SW is no current. But then you give a wonderful analogy, asking if the ocean is a current.

Plasma oscillations, in specific the plasma frequency. This is the "natural" osciallation frequency for a plasma, where ions are a neutralizing, immobile background, and the electrons "do all the work". The frequency follows directly from the continuity and momentum equations in the cold plasma approach, as a second order differential equation:

omega_p = sqrt( n e^2 / epsilon_0 m_e)

dropping the cold plasma approach one gets a dispersion relation, i.e. a description of the frequency dependend on the wavelength

omega^2 = omega_p^2 + 1.5 k^2 v_e^2

where v_e is the electron thermal velocity and k is the wave vector.

I have not been able to find any references that one can take the plasma oscillations as an AC current, and personally I think that you cannot look at it that way, as there is no work done. The other way around, I just saw that in tokamaks they use the plasma frequency to energize the plasma.

Anywho! let's continue, and try to edumacate eachother. But let us start with simple things and slowly continue to more complicated cases. To shock everyone now: THERE ARE CURRENTS IN THE SOLAR WIND. But I hope you understand this statement in view of the analogy that Ian made.

Okay, back to the drawing board.

[czeslaw]

We will come to the right conclusion soon.
You agree that there are charge micro oscillations in a neutral plasma.

All planets are surrounded by the hot, magnetized, supersonic collisionless solar wind plasma capable of conducting electrical current and carrying a large amount of kinetic and electrical energy.

What the electrical energy can do a work ?
For example:
There is a solenoid current in a spaceship moving far in the solar wind. An alternating electric current could be induced in this solenoid. The frequencies and strength of this current is difficult to estimate.

The frequency of the electron in a plasma depends on their density and for example if there are 10^5 electrons in 1 cm^3 their frequency in plasma will be 2,8 MHz..

A frequency of an induced current depends of many evets
BzN = Strong northward Bz for extended period
BzS = Strong southward Bz for extended period
EyC = Change in Ey=VxBz
HSS = Very high speed stream for extended period
IMC = Interplanetary magnetic cloud
IR = Interaction Region
IS = Interplanetary shock
LSS = Very low speed stream for extended period
MISC = Miscelaneous, which may include a very broad range of features
PC = Pressure change
SBC = Interplanetary sector boundary crossings (usually in a set)

The electrons passing the solenoid oscillate in plasma and plasma move relatively to solenoid. It causes tremendous frequency. There is question now if the electrons in the solenoid could move according to this frequency.

[tusenfem]

We will come to the right conclusion soon.
You agree that there are charge micro oscillations in a neutral plasma.

Yes, there are plasma oscillations

All planets are surrounded by the hot, magnetized, supersonic collisionless solar wind plasma capable of conducting electrical current and carrying a large amount of kinetic and electrical energy.

Which electric energy do you mean?

What the electrical energy can do a work ?
For example:
There is a solenoid current in a spaceship moving far in the solar wind. An alternating electric current could be induced in this solenoid. The frequencies and strength of this current is difficult to estimate.

The frequency of the electron in a plasma depends on their density and for example if there are 10^5 electrons in 1 cm^3 their frequency in plasma will be 2,8 MHz..

Well, there are only like 10 particles per cm^3 in the solar wind, but that would only decrease your frequency by a factor 100.
Why is there a solenoid current in the spaceship? Do the astronauts set that up, or do you want to induce that current or ...?
I do not think one can induce a current using the plasma frequency.

A frequency of an induced current depends of many evets
BzN = Strong northward Bz for extended period
BzS = Strong southward Bz for extended period
EyC = Change in Ey=VxBz
HSS = Very high speed stream for extended period
IMC = Interplanetary magnetic cloud
IR = Interaction Region
IS = Interplanetary shock
LSS = Very low speed stream for extended period
MISC = Miscelaneous, which may include a very broad range of features
PC = Pressure change
SBC = Interplanetary sector boundary crossings (usually in a set)

The electrons passing the solenoid oscillate in plasma and plasma move relatively to solenoid. It causes tremendous frequency. There is question now if the electrons in the solenoid could move according to this frequency.

Care to explain how you think it is these influences work? Maybe first look into the induction process itself in e.g. "Classical Electrodynamics" by Jackson.
Fron the list you put up there, it looks like you just copied what processes are responsible for magnetotail dynamics, and we don't want to go there quite yet.

[czeslaw]

There is very low charge density and probably not many electrons in this solenoid will move in an alternating current. The very close to solenoid particle may induce an alternating current. Any way, there is such a possibility. It is not possible to measure its frequency because of the events as above, it will be more or less chaotic. Any way this current, although chaotic may carry an energy and do some work, I think.

[tusenfem]

There is very low charge density and probably not many electrons in this solenoid will move in an alternating current. The very close to solenoid particle may induce an alternating current. Any way, there is such a possibility. It is not possible to measure its frequency because of the events as above, it will be more or less chaotic. Any way this current, although chaotic may carry an energy and do some work, I think.

First you have to explain how the events that you listed change the frequency, or at least how you think they change the frequency.
I still do not think that the micro-osciallations, that are these plasma oscillations, will induce a current in a solenoid. Maybe there is someone here that knows more about that, or maybe I have an idea, have to look it up.
But then arguing that the current is chaotic, then you negate what you proposed, and no current will be present, either chaotic outside will induce nothing inside or chaotic inside will add up to nothing
By the way, does the oscillating current induce the current solenoid, or does the associated magnetic field produce the induced current???
I think I found the solution, as the plasma waves are electrostatic modes, there is no magnetic field associated, so there is no induction. From Kivelson and Russell, Introduction to space physics, Chapter 12, page 374, and the analysis before, discussing the plasma frequency and the Langmuir waves that logically follow from them after dropping the cold plasma limit.

[czeslaw]

Here are the solar wind data updated every 5 minutes – There are plasma density, velocity and associated magnetic field http://www.sel.noaa.gov/SWN/sw_dials.html

[czeslaw]

A plasma of the solar wind and a solenoid may create a system of a double layers.
The global evolution of a DL-containing plasma system (close to solenoid) is the result of the mutual influence of two or more DLs coupled by the current flowing through them. The temporal variation of the current are correlated with the space-temporal variations of the parameters of the above plasma.
http://66.102.7.104/search?q=cache:r4ACkKNbX4IJ:epsppd.epfl.ch/Montreux/pdf/P2_035.pdf

[Karl]

A plasma of the solar wind and a solenoid may create a system of a double layers.
The global evolution of a DL-containing plasma system (close to solenoid) is the result of the mutual influence of two or more DLs coupled by the current flowing through them. The temporal variation of the current are correlated with the space-temporal variations of the parameters of the above plasma.
http://66.102.7.104/search?q=cache:r4ACkKNbX4IJ:epsppd.epfl.ch/Montreux/pdf/P2_035.pdf+plasma+double+layer+alternating+current &hl=pl

Ummmmmm. . .

Could you please explain why you think this is applicable to the solar wind other than just having your search words in it?

[czeslaw]

This link is general about plasma. Its URL is too long and I will cut it.
The reason is that solar wind is a plasma too and there are double layers in the solar wind. The electrons are accelerated in DLs. Such a movements may create additionally currents. I think.

[Nereid]

The reason is that solar wind is a plasma too and there are double layers in the solar wind.
Where are they? How do you tell where they are? What are their characteristics?Such a movements may create additionally currents. I think.Additional to what?
What would the characteristics of these currents be?

[Karl]

The reason is that solar wind is a plasma too and there are double layers in the solar wind. The electrons are accelerated in DLs. Such a movements may create additionally currents. I think.

The presumed double layers observed in the solar wind are quite weak, ~1mv in potential. And that's assuming this interpretation is correct.

Weak double layers in the solar wind (http://www.arcetri.astro.it/~solwind/abstract/node173.html)

[czeslaw]

Thank you Karl for this super link. This question about a currents in the solar wind may be not solved yet.

The velocity distribution functions (VDFs) of electrons as measured in the solar wind show pronounced deviations from a Maxwellian. They seem to be composed of a thermal core and energetic tails, called halo. These VDFs can be fitted very well by kappa distributions. The formation of the energetic tails in the corona or in the solar wind is investigated. http://www.arcetri.astro.it/~solwind/abstract/node156.html

The dissipation of large-scale magnetohydrodynamic waves and turbulence in the collisionless solar wind is still not understood well. Dispersive plasma waves and associated wave-particle interactions are a key to this problem. http://www.arcetri.astro.it/~solwind/abstract/node140.html

[tusenfem]

Here are the solar wind data updated every 5 minutes – There are plasma density, velocity and associated magnetic field http://www.sel.noaa.gov/SWN/sw_dials.html

Okay, czeslaw, you are sidestepping again here. I write you how and what and you post a link with solar wind data. We all know that the solar wind has density, velocity and magnetic field. It does not take away what I posted earlier, about no induction in your solenoid.

A plasma of the solar wind and a solenoid may create a system of a double layers.
The global evolution of a DL-containing plasma system (close to solenoid) is the result of the mutual influence of two or more DLs coupled by the current flowing through them. The temporal variation of the current are correlated with the space-temporal variations of the parameters of the above plasma.

If you can come up with a REASONABLE explanation hoe the solar wind and the solenoid create a DL, I would love to hear it. What is your solenoid made of? It was in your spacecraft so I think it is just a coil in the freight room. But I guess that they can hang it outside into the solar wind. But that is not going to get you any double layers.

[tusenfem]

Thank you Karl for this super link. This question about a currents in the solar wind may be not solved yet.

The velocity distribution functions (VDFs) of electrons as measured in the solar wind show pronounced deviations from a Maxwellian. They seem to be composed of a thermal core and energetic tails, called halo. These VDFs can be fitted very well by kappa distributions. The formation of the energetic tails in the corona or in the solar wind is investigated. http://www.arcetri.astro.it/~solwind/abstract/node156.html

The dissipation of large-scale magnetohydrodynamic waves and turbulence in the collisionless solar wind is still not understood well. Dispersive plasma waves and associated wave-particle interactions are a key to this problem. http://www.arcetri.astro.it/~solwind/abstract/node140.html

so nice, isn't it, czeslaw, to just copy and paste something that does not have anything to do with the question you asked before or the answer you got.

[czeslaw]

There are two different questions.
The first is a direct current in the solar wind and it is probably not exactly solved till now (according to links above).

The second is an alternating current caused by a plasma of the solar wind.
My idea is that charge oscillations in the solar wind will induce the charge oscillations in a conductor moving relatively to the solar wind. This charge oscillations in a conductor create an alternating electric current.
I do not know now how to prove it but I will do it, I think.

[tusenfem]

There are two different questions.
The first is a direct current in the solar wind and it is probably not exactly solved till now (according to links above).

The links have NOTHING to do with currents in the solar wind. It just discussed particle distribution funtions, that are not Maxwellian, but kappa distributions, or even better they are bi-kappa distributions (Leubner and Voros, 2004).

The second is an alternating current caused by a plasma of the solar wind.
My idea is that charge oscillations in the solar wind will induce the charge oscillations in a conductor moving relatively to the solar wind. This charge oscillations in a conductor create an alternating electric current.
I do not know now how to prove it but I will do it, I think.

I have already said above that the oscillations are electrostatic, so they cannot induce a current in your solenoid. This is also the reason that you need the Electric Wave Instrument onboard spacecraft, which makes a spectrogram of the electric field measurements, to get the upper-hybrid frequency, which is for all purposes in space physics equal to the electron plasma frequency. There is no such signal in the magnetic field spectrogram.
But I would love to see your theory here with equations, etc.

[czeslaw]

The solution of the problem will be in a structure of the solar wind. The plasma of the solar wind is not homogeneous because of the changes in a solar emission and dusty space.

Regardless of scale, the motion of charged particles produces a self-magnetic field that can act on other collections of particles or plasmas, internally or externally. Plasmas in relative motion are coupled via currents that they drive through each other. Currents are therefore expected in a universe of inhomogeneous astrophysical plasmas of all sizes. http://public.lanl.gov/alp/plasma/elec_currents.html

There are permanently the double layers created on the different scales with the electric currents between them. We may say, the solar wind as a whole neutral plasma do not carry a current from point A to point B, but there are multitude local and tentative electric currents in all directions in the space between the points A and B.

[captain swoop]

Why do you keep repeating all this when you have been shown it is wrong?

[czeslaw]

What is wrong?
There are charge oscillations in a plasma.
There are locally and tentative double layers in the solar wind.
There are locally currents in this double layers.
All that is right.

[tusenfem]

What is wrong?
There are charge oscillations in a plasma.
There are locally and tentative double layers in the solar wind.
There are locally currents in this double layers.
All that is right.

yes there are charge oscillations
yes, there seems to be evidence that there are DLs in the solar wind
as these are weak DLs (do you know what weak DLs are?) the current is most likely negligible.

It is not stating the obvious, where you go wrong, it is by putting one and one together where you obtain three.

As the Dutch say: Je hoort de klok wel luiden, maar je weet niet waar de klepel hangt.

[czeslaw]

Mit Deine Hilfe, ich werde gleich wissen welche Glocke da ist.

I didn't say there is a strong electric current. I want just prove - there are many tentative, local electric currents in the whole electrically neutral solar wind.

[tusenfem]

oops, that was a no no from me, writing something in Dutch without translating it. I guess czeslaw go the picture.
(translation: you hear the bell ring, but you don't know what is making the sound)

Czeslaw, there are a bezillion currents in the solar wind, remember the ocean analogy. now you have to figure out, what do you want to do with these currents. you have basically taken over Ian's thread here.
The OP was about, is the solar wind as a whole an outflowing current, and the answer was no.
Yes, there are currents in the solar wind, because there are magnetic structures in the solar wind, like CMEs.
Maybe Czeslaw should first tell us WHAT he wants to do with WHICH currents.

[czeslaw]

I am satisfied that we have came to the right conclusion, at least.

What the currents in the solar wind can do, it might be a new thread.
They are investigated by astronomers still , if they heat the plasma and how it helps to keep the plasma together.

Any way, this discussion was hard but succesfully.

[tusenfem]

WOW, care to share with us what the right answer is?
At least with Ian's question, that the SW is not an outward flowing current.
There are still a lot of questions that you need to answer, from previous messages, I guess a new thread would be a good idea.

[Mosheh Thezion]

i dont see the point of the arguement, since if the solar wind has a frequency, it will be to high to be useful, otherwise it will be slow, based on the variations of thr suns magnetic field which changes every 11 years.

now... thats a low frequency... like.. .000000000000001 waves per sec... or something ridiculous like that.

-MT

[czeslaw]

The plasma in the solar wind seems to be according to our discussion in a hierarchic system. There are:

1. The electrostatic micro oscillations between charged particles in the plasma.
2. The weak double layers with their electric currents caused by temperature differences, cosmic rays, magnetic, gravitational fields…
3. The electric neutral clouds of plasma ejected by a sun’s activity.
4. A plasma of the whole solar heliosphere.
5. Probably system of the star’s magnetospheres causing galactic electric currents in their magnetopauses.

[Karl]

i dont see the point of the arguement, since if the solar wind has a frequency, it will be to high to be useful

The solar wind is a plasma, therefore it has a plasma frequency, which varies depending on the local plasma density.

It is very useful for measuring the plasma density.

[tusenfem]

i dont see the point of the arguement, since if the solar wind has a frequency, it will be to high to be useful

The solar wind is a plasma, therefore it has a plasma frequency, which varies depending on the local plasma density.

It is very useful for measuring the plasma density.

Ohhh, well spoken, I use it every day :lol:


1. The electrostatic micro oscillations between charged particles in the plasma.
2. The weak double layers with their electric currents caused by temperature differences, cosmic rays, magnetic, gravitational fields…
3. The electric neutral clouds of plasma ejected by a sun’s activity.
4. A plasma of the whole solar heliosphere.
5. Probably system of the star’s magnetospheres causing galactic electric currents in their magnetopauses.


In order to have a hierarchy, though, I think usually the one has something to do with the other, and are in a relational connection.
I take argument with #2 (guess that was to be expected) and I am not sure about #5.

But hey, next thread!

[czeslaw]

I have an interest about the forces in the galactic plasma. May be, the solar wind is a good piece of a plasma, which we can investigate.

It is very difficult to keep the plasma together in the laboratory on the Earth (strong magnetic field, high energy lasers ...)

I have a question, if there are in a space (solar wind) many plasmas, they may interact with each other and perhaps even support their life. If there are many local and tentative currents , they will hold all system together in the heliosphere .

I don’t know how to call the next thread.

[Nereid]

I have an interest about the forces in the galactic plasma. May be, the solar wind is a good piece of a plasma, which we can investigate.

It is very difficult to keep the plasma together in the laboratory on the Earth (strong magnetic field, high energy lasers ...)

I have a question, if there are in a space (solar wind) many plasmas, they may interact with each other and perhaps even support their life. If there are many local and tentative currents , they will hold all system together in the heliosphere .

I don’t know how to call the next thread.
I started one for you: Electric currents in the ISM? (http://www.badastronomy.com/phpBB/viewtopic.php?p=518538#518538), hope you don't mind.

In any case, there's not much point talking about the ISM or IGM here in this 'solar wind' thread.