Hubble finds source of Magellanic Stream

Aug 08, 2013
These images show wide and close-up views of a long ribbon of gas called the Magellanic Stream, which stretches nearly halfway around the Milky Way. Credit: Credit for the radio/visible light image: David L. Nidever, et al., NRAO/AUI/NSF and Mellinger, LAB Survey, Parkes Observatory, Westerbork Observatory, and Arecibo Observatory. Credit for the radio image: LAB Survey

(Phys.org) —Astronomers using the NASA/ESA Hubble Space Telescope have solved the 40-year-old mystery of the origin of the Magellanic Stream, a long ribbon of gas stretching nearly halfway around the Milky Way. New Hubble observations reveal that most of this stream was stripped from the Small Magellanic Cloud some two billion years ago, with a smaller portion originating more recently from its larger neighbour.

The Magellanic Clouds, two orbiting our galaxy, are at the head of a huge gaseous filament known as the Magellanic Stream. Since the Stream's discovery in the early 1970s, astronomers have wondered whether this gas comes from one or both of the satellite galaxies. Now, new Hubble observations show that most of the gas was stripped from the Small Magellanic Cloud about two billion years ago—but surprisingly, a second region of the stream was formed more recently from the Large Magellanic Cloud.

A team of astronomers determined the source of the gas by using Hubble's Cosmic Origins Spectrograph (COS), along with observations from ESO's Very Large Telescope, to measure the abundances of heavy elements, such as oxygen and sulphur, at six locations along the Magellanic Stream. COS detected these elements from the way they absorb the ultraviolet light released by faraway as it passes through the foreground Stream. Quasars are the brilliant cores of active galaxies.

The team found low abundances of oxygen and sulphur along most of the stream, matching the levels in the Small Magellanic Cloud about two billion years ago, when the gaseous ribbon was thought to have been formed.

In a surprising twist, the team discovered a much higher level of sulphur in a region closer to the Magellanic Clouds. "We're finding a consistent amount of heavy elements in the stream until we get very close to the Magellanic Clouds, and then the heavy element levels go up," says Andrew Fox, a staff member supported by ESA at the Space Telescope Science Institute, USA, and lead author of one of two new papers reporting these results. "This inner region is very similar in composition to the Large Magellanic Cloud, suggesting it was ripped out of that galaxy more recently."

This discovery was unexpected; computer models of the Stream predicted that the gas came entirely out of the Small Magellanic Cloud, which has a weaker gravitational pull than its more massive cousin.

"As Earth's atmosphere absorbs , it's hard to measure the amounts of these elements accurately, as you need to look in the ultraviolet part of the spectrum to see them," says Philipp Richter of the University of Potsdam, Germany, and lead author on the second of the two papers. "So you have to go to space. Only Hubble is capable of taking measurements like these."

All of the Milky Way's nearby have lost most of their gas content—except the Magellanic Clouds. As they are more massive than these other satellites they can cling on to this gas, using it to form new stars. However, these Clouds are approaching the Milky Way and its halo of hot gas. As they drift closer to us, the pressure of this hot halo pushes their gas out into space. This process, together with the gravitational tug-of-war between the two Magellanic Clouds, is thought to have formed the Magellanic Stream.

"Exploring the origin of such a large stream of gas so close to the Milky Way is important," adds Fox. "We now know which of our famous neighbours, the Magellanic Clouds, created this gas ribbon, which may eventually fall onto our own galaxy and spark new star formation. It's an important step forward in figuring out how galaxies obtain gas and form new stars."

Explore further: Astronomers find 'cousin' planets around twin stars

More information: These results are presented in a set of two papers, both published in the 1 August issue of The Astrophysical Journal.

The first of these papers is entitled "The COS/UVES absorption survey of the Magellanic Stream: I. One-tenth solar abundances along the body of the stream".

The second of these papers is entitled "The COS/UVES absorption survey of the Magellanic Stream: II. Evidence for a complex enrichment history of the stream from the Fairall 9 sightline".

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cantdrive85
1 / 5 (15) Aug 08, 2013
The Magellanic Clouds, two dwarf galaxies orbiting our galaxy, are at the head of a huge gaseous filament known as the Magellanic Stream.


The "gaseous" filament is a filament because it is plasma, plasma organizes itself into filamentary structures. This plasma filament stream (or birkeland current) connects the MW to the LMC and SMC. It's the "powerline" that supplies the electric energy to power the celestial objects.
GSwift7
2.2 / 5 (9) Aug 08, 2013
No, this would be cold gas, not plasma.
cantdrive85
1.3 / 5 (13) Aug 08, 2013
Don't assume a plasma has to be "hot", plasmas exist from near absolute zero to temps in excess of 10^9 K. Also, the CIV of this "gas" is readily met in this fast moving cloud.
http://www.plasma...2000.pdf
There is also the likelihood this "cloud" resides within the MW's magnetic field, and therefore it's non-zero electric field. The idea this filamentary "gas" that shows plasma behavior is not plasma seems a ridiculous notion.

Oh wait, of course, this is not a birkeland current..
http://www.thunde...rrent-3/
barakn
3.7 / 5 (6) Aug 08, 2013
Oh, great, another link from our favorite website http://www.thunde...rrent-3/
HannesAlfven
1.3 / 5 (12) Aug 08, 2013
It's interesting that an article which plainly strives to explain the filamentary nature of the Magellanic Clouds would be assumed to be an article about gas rather than plasma. After all, a gas can begin to behave as a plasma with less than 1% ionization. It seems that this would tend to tilt the odds that these filamentary structures are likely filamentary for the same reason that laboratory plasmas are filamentary.

A quick Google search on "critical ionization velocity gerrit verschuur" reveals a number of papers pointing to apparent CIV's associated with the "knots" within many of the observed interstellar filaments. That's particularly problematic for the gas-only view, since CIV's result when charged particles are slammed at enormous velocities into neutral gases. This tends to emit very particular redshifts, and some of these redshifts are anomalous to the inference that the redshift results strictly from velocity, given the inferred location of these clouds.
HannesAlfven
1.4 / 5 (10) Aug 08, 2013
From page 55 of Gerrit Verschuur's "The Invisible Universe" ...

--

6.6. Anomalous Velocity Hydrogen

Not all is understood about the distribution of HI in the Milky Way. For example,
large areas of sky are found to contain HI moving at velocities that are not expected
if the gas is confined to the plane of the Galaxy. In particular, when a radio telescope
is pointed above or below the galactic plane, only relatively local gas traveling at
velocities between ±20 km/s with respect to zero, defined in terms of the average
random motion of stars near the sun, should be observed. However, HI at very high
negative velocities, which indicates motion toward us, is found at high galactic
latitudes. These structures are known as high-velocity clouds, although detailed
maps of such features show them to be filamentary instead of cloud-like.

--

Verschuur's numerous papers are far more specific that these velocities oftentimes correspond to very specific CIV's -- and even WMAP hot spots!
cantdrive85
1.3 / 5 (13) Aug 08, 2013
Oh, great, another link from our favorite website http://www.thunde...rrent-3/

"Being immature is one thing, but acting childish is a whole different category. Immaturity is a phase, childishness is a choice." Unknown

"I'd like to see things from your point of view, but I can't seem to get my head that far up your ass." anon
Gmr
3 / 5 (10) Aug 08, 2013
Oh, great, another link from our favorite website http://www.thunde...rrent-3/

You don't understand! Plasma is magic! It can read your mind, it can be cold or hot, ionized or not, and everything in-between! It's magnetic, electric, eclectic, sullen, a lover for all seasons!

It is pure Joy - and Joy cannot be confined in your "theories" and "science!"
cantdrive85
1.3 / 5 (13) Aug 09, 2013
Actually, you don't understand. The Electric Universe follows sound electrical engineering principles and space plasma science as recognized by the Institute of Electrical and Electronic Engineers (IEEE). This is where EU papers are published, with electric engineers who understand plasma physics, you know the ones we rely upon for "safe" nuclear power, semiconductor manufacture, and many other aspects of modern society.

It was the theoreticians who failed to achieve the sustained nuclear reactions based on their theoretical models proposed so many years ago. Yet, these are the same models astrophysicists use. This is what Alfven meant when he said;
"astrophysics is the playground of theoreticians who have never seen a plasma in a laboratory. Many of them still believe in formulae which we know from laboratory experiments to be wrong."

It is the BB and much of the "standard theory" which is magic, REQUIRES magic. The EU and PC only require logic.
Gmr
3 / 5 (10) Aug 09, 2013
I was wrong! The universe is actually a giant circuit board! It's true! Electrical engineers told me so! And if anyone knows interstellar physics and cosmology it's a guy with a soldering iron!

That still, though, doesn't explain the subsequent need for a Cosmological Nine-Volt... it's a gap that must be filled by another, better theory I suppose.
Gmr
3 / 5 (8) Aug 09, 2013
I'm actually curious about this gas stripping - it seems to occur in smaller or spiral galaxies that enter the inner regions of large clusters, and I'm wondering if it is "ram pressure stripping" as is implicated in other instances or an effect of dark matter of some kind - the interaction of halos, as it were, changing the profile of "subordinate" galaxies, and if this isn't related to a similar phenomenon as what happens to galaxies in larger clusters.
cantdrive85
1.3 / 5 (13) Aug 09, 2013
You people are so effing ridiculous. We're dealing with plasma, experts in plasma should be tackling the problems, such as the "non-local transport phenomena". Here's a paper on plasma networking hosted at the IAEA,
http://www-pub.ia...p_17.pdf

Just as you can't seem to find 85% of the universe (DM), we can't seem to find the 9 volt. Billions later, still no DM, yet the search continues.
The battery may be more simple than you think, you see, the motion of plasma across weak magnetic fields can lead to electromotive forces, which can then be transported over large distances via Birkeland currents, along which an EM pinch event can transpire. Processes scalable over many orders of magnitude. No magic is involved, no creation event hypothesized. Don't be offended by the electrical engineers, just learn from their real life experiences from actually working with plasma. Interdisciplinary studies should be encouraged, yet they're ridiculed. Sad!
Greenwood
5 / 5 (6) Aug 09, 2013
The Electric Universe follows sound electrical engineering principles and space plasma science as recognized by the Institute of Electrical and Electronic Engineers (IEEE). This is where EU papers are published, with electric engineers who understand plasma physics...


IEEE do not endorse EU, they simply published a few papers on it, that does not mean it's correct. Interestingly that very same journal also publishes something you consider goes against plasma physics, magnetic reconnection. It's funny because I'm sure you said a) they were experts and b) electrical engineers would laugh at reconnection. So either IEEE publishing a paper does not mean everything is correct in the paper or everything you spout about MR is nonsense. I'd put my money on both but there you go.

EU may not require magic, who can say given that no one has actually shown it can explain anything. Without modeling these systems it's pure speculation.
rug
3.2 / 5 (9) Aug 09, 2013
As a member of IEEE I take great offence to the rambleings of cantdrive. Yes, there have been papers published on plazma as there should be. None of them however try to explain whats going on in the universe. That is not our place. We strive to provide valid informatoin to the rest of the technilogical engineers out there. This educates our members (such as me) and maybe spark an idea for a new invention. The better informed the engineers are the more employable they will be.

cantdrive making stuff up just to get a rise out of people. I don't think he believes it any more then the rest of the world does. He's just a troll and one to be ignored.
rug
3.7 / 5 (6) Aug 09, 2013
only relatively local gas traveling at velocities between ±20 km/s with respect to zero


With respect to 0 of what? Oh thats right, just another troll trying to get some attention.
cantdrive85
1 / 5 (9) Aug 09, 2013
None of them however try to explain whats going on in the universe.

Do I ramble, absolutely! Do I think I'm right about anything/everything? Yes and an emphatic NO! Am I trolling? Many think so, but I'm only trying to incite honest discussion. Most prefer to respond with derision and contempt in defense of their own beliefs, regardless of the approach taken by myself and others.

To claim, "none try to explain...the universe" is silly. The universe is composed of 99.9+% plasma, any knowledge gained of plasma will most likely be applicable somewhere in this vast universe. Don Scott, Anthony Peratt, among others, are IEEE members who are proposing to explain "what's going on in the Universe".

Seems as if you're making stuff up too!
rug
2.3 / 5 (3) Aug 09, 2013
They may be IEEE members but you said IEEE is publishing the papers. This is completely false. I am not making stuff up but nice to know you are. Since you just admitted it.
cantdrive85
1 / 5 (10) Aug 09, 2013
only relatively local gas traveling at velocities between ±20 km/s with respect to zero


With respect to 0 of what? Oh thats right, just another troll trying to get some attention.


If you want to understand something, don't stop reading. The answer to your question is right there in the very same sentence;
"defined in terms of the average random motion of stars near the sun, should be observed."
And that was not written by HA, it was written by Gerrit Verschuur PhD and radio astronomer, the man who pioneered the measurement of the interstellar magnetic field using the 21-cm Zeeman effect technique.

Who's trolling by making things up?
cantdrive85
1 / 5 (9) Aug 09, 2013
'Real Properties of Electromagnetic Fields and Plasma in the Cosmos' by Don Scott PhD IEEE
Published in IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. 35, NO. 4, AUGUST 2007

The Evidence For Electrical Currents in Cosmic Plasma, A. L. Peratt, IEEE Trans. Plasma Sci. 18, p.26 (1990) (548KB).

Equilibrium of Intergalactic Currents, B. E. Meierovich and A. L. Peratt, IEEE Trans. Plasma Sci. 20, p.891, 1992 (152KB)

Model of the Plasma Universe, H. Alfvén, IEEE Trans. Plasma Sci. Vol PS-14, 1986 (1.1MB).

Cosmology in the Plasma Universe: An Introductory Exposition, H. Alfvén, IEEE Trans. Plasma Sci. 18, 1990 (7.9MB).

What Laboratory-Produced Plasma Structures Can Contribute to the Understanding of Cosmic Structures Both Large and Small, W. H. Bostick, IEEE Trans. Plasma Sci., vol. PS-14, n. 6, 1985

Shall ramble on, or will you admit to making stuff up too.

"Mistakes are always forgivable, if one has the courage to admit them."
Bruce Lee
rug
2.3 / 5 (3) Aug 09, 2013
It's a nonsensical statement. To have a relation of 0 you must first have a point of reference. Having motion as a reference point can't be done. Now if the sun was the reference point then it would make sense. Without a frame of reference the statement does not make any sense.
You have already admitted your making things up even though your intention was to make it look as though I am making stuff up.
Seems as if you're making stuff up too!


I have no problems with a discussion of where science is lacking in understanding. I have no problem discussing other possible theories. However, I will not bother to discuss theories that have already been proven false. Like your cold plasma. Take a look at the wiki page. Turns out, plasma cools and looses the ionization need to be a plasma.

Since your not even bothering to look up the real information instead of one or two sites that only preach what you are preaching then there is no point in considering a real discussion with you.
rug
3.4 / 5 (5) Aug 09, 2013
'Real Properties of Electromagnetic Fields and Plasma in the Cosmos' by Don Scott PhD IEEE
Published in IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. 35, NO. 4, AUGUST 2007.....


Hmmmm lets see I didn't become a member until 2001 so the garbage has already been published and gone. The ones after are simply studies of plasma. You know, like stars. Though I'm not even 10% sure these are real publishing either. I could go back in the archives and look, but I really don't feel like it so I'll just ignore you.
cantdrive85
1 / 5 (9) Aug 09, 2013
Like your cold plasma. Take a look at the wiki page. Turns out, plasma cools and looses the ionization need to be a plasma.


Wiki? Maybe you should "edit" that page since anyone is able to do so. This is pulled from 'Perspectives on Plasma' found at
http://www.plasma...sics.htm

"For temperature (or energy), some plasma crystal states produced in the laboratory have temperatures close to absolute zero. In contrast, space plasmas have been measured with thermal temperatures above 10+9 degrees Kelvin and cosmic rays (a type of plasma with very large gyroradii) are observed at energies well above those produced in any man-made accelerator laboratory. Considering Powers of 10 is useful for grasping the unique way in which plasmas are radically multi-scale in space, energy and density."

That temp range, taken with the fact that there is a magnetic field present and the velocity of the "cloud" is well in excess of the CIV ratios suggest it is in fact a plasma.
cantdrive85
1 / 5 (8) Aug 09, 2013
Since your not even bothering to look up the real information

Yep, the IEEE is full of cranks!
cantdrive85
1 / 5 (9) Aug 09, 2013
You people are so effing ridiculous. We're dealing with plasma
The problem just is, we just aren't dealing with plasma. I really don't understand, why/how the talking about plasma could explain or contribute to the fact, that our Milky way is surrounded with dwarf galaxies, which are gradually sucked and scattered with gravitational forces. Your fascination with plasma effects is ridiculously fascinating.

As NASA states, 99.9+% of the Universe is plasma, and plasma is dominated by EM forces, I fail to see how the importance is not remarkably obvious! I also don't understand this fascination with the weakest and most chaotic of the natural forces, gravitation.
Q-Star
3 / 5 (6) Aug 09, 2013
As a member of IEEE I take great offence to the rambleings of cantdrive. Yes, there have been papers published on plazma as there should be. None of them however try to explain whats going on in the universe. That is not our place. We strive to provide valid informatoin to the rest of the technilogical engineers out there. This educates our members (such as me) and maybe spark an idea for a new invention. The better informed the engineers are the more employable they will be.

cantdrive making stuff up just to get a rise out of people. I don't think he believes it any more then the rest of the world does. He's just a troll and one to be ignored.


Thank ya for speaking up. We really need more input from actual IEEE members (as opposed to trolls who never even really read any of their papers, they depend on crank web sites to read them and tell them what they say.). I only regret that I am limited to a five vote.
Q-Star
3.5 / 5 (8) Aug 09, 2013
Am I trolling? Many think so, but I'm only trying to incite honest discussion. Most prefer to respond with derision and contempt in defense of their own beliefs, regardless of the approach taken by myself and others


I will put the lie to that one. Total BS,,,,,, I even went so far as to give ya a couple of very public and sincere apologies if I had offended ya. And asked if ya wanted to discuss the actual science.

Ya made it quite clear that ya didn't want to discuss the topic, all ya wanted to discuss is how stupid, uneducated, and foolish the astrophysical community was.

So don't present yourself as a reasonable, much abused victim, ya bit at me for having the temerity to approach ya. That is why I have not risen to many attempts ya have made to bait into your sand box. And why I will continue to do so.

But I wanted everyone to realize that ya are a liar, and troll. All ya want is to disrupt anyone trying to discuss real science,,, that's how ya measure your worth.
cantdrive85
1 / 5 (10) Aug 09, 2013
Well, 99.9 % of matter is formed with quarks, so why we aren't talking about quantum chromodynamics by the same "logic" (logical fallacy actually)?


Because the classical physics approach to the nature of magnetism and gravity and their relationship to the electrical structure of matter is adequate.
http://exvacuo.fr...ight.pdf

Thank ya for speaking up. We really need more input from actual IEEE members (as opposed to trolls who never even really read any of their papers,

He doesn't even acknowledge they exist, let alone read them, but I guess that gives value to his opinion gleaned from ignorance.

Gmr
3 / 5 (6) Aug 09, 2013
As NASA states, 99.9+% of the Universe is plasma

Well, that might be true of ~4% of the universe, but I don't think it is true of the dark matter or dark energy components, at least as far as we know. And I'd doubt it applies to 99.9+% of that ~4%.

I also don't understand this fascination with the weakest and most chaotic of the natural forces, gravitation.

Because it has no charge or sign or "negative" or, apparently, range limit.

Because of all of the forces, despite its weakness, it dominates on the largest scales of the universe, possibly because it is so different from all of the other forces.

Because of all of the forces, it is the least understood with regard to origins.

Because, unlike all of the other more powerful short-range forces, it can be powerful enough to almost completely remove something from any further interaction with the rest of the universe.

Because it can bend light.

I'm running out of room.
cantdrive85
1 / 5 (9) Aug 09, 2013
all ya wanted to discuss is how stupid, uneducated, and foolish the astrophysical community was.

"This is beyond my imagination" Subrahmanyam Chandrasekhar

Arp's submitted paper was "beyond his imagination" due to the fact it would have totally falsified his own theory on black holes (and BB), and he knew it. I look at history and see how many brilliant scientists and generalists are treated as above when their ideas don't conform with that of the accepted norm. Many, yourself included, portray this ideal that scientists are always welcoming to new views and ideas. Reality couldn't be further from the truth, Arp's experience is the norm rather than the exception. Scientists display all the frailties and imperfections of every other segment of society, they are far from the ideal.
Just because I find ya condescending and egotistical, the type who talks down to ya from his pulpit doesn't mean I'm a liar. Besides, your POV is the BB and GR, no science there to discuss.
cantdrive85
1.4 / 5 (10) Aug 09, 2013
As NASA states, 99.9+% of the Universe is plasma


Well, that might be true of ~4% of the universe, but I don't think it is true of the dark matter or dark energy components, at least as far as we know. And I'd doubt it applies to 99.9+% of that ~4%.

From a PC/EU POV, that "other" 95+% is chaff, spurious, totally unnecessary to explain what we observe. The hypothetical DE/DM is conjured up to account for the misrepresented and misunderstood electric force, that which is 39 orders of magnitude stronger than gravity.

Because of all of the forces, despite its weakness, it dominates on the largest scales of the universe, possibly because it is so different from all of the other forces.

EM obeys the longest range force laws, 1/r.

Because of all of the forces, it is the least understood with regard to origins.

So it's okay to give it supernatural abilities?

Because it can bend light.

EM is light, and can certainly be bent by it.

barakn
5 / 5 (5) Aug 09, 2013
EM obeys the longest range force laws, 1/r. -cantdrivel85

No, the force of an electrical point charge goes as 1/r^2. You're probably thinking of electrostatic potential energy. Once again your complete ignorance of physics is showing.
cantdrive85
1 / 5 (9) Aug 10, 2013
EM obeys the longest range force laws, 1/r. -cantdrivel85

No, the force of an electrical point charge goes as 1/r^2. You're probably thinking of electrostatic potential energy. Once again your complete ignorance of physics is showing.


It's explained over here, from a paper presented at an IAU symposium;
http://adsabs.har...40..143P

Greenwood
5 / 5 (2) Aug 10, 2013
EM obeys the longest range force laws, 1/r. -cantdrivel85


This may be so under certain conditions (it is by no means universally true) but that doesn't prove EM forces are dominant in the universe. Even with a 1/r^2 dependence a simple comparison like your would say it was dominant everywhere, as the coupling constant is much greater. However, this is not so. Unlike gravity there are positive and negative charges. EM forces can effectively be screened out, particularly well in a plasma.

EM is light, and can certainly be bent by it.


Please tell us how.
cantdrive85
1 / 5 (8) Aug 10, 2013
This may be so under certain conditions (it is by no means universally true) but that doesn't prove EM forces are dominant in the universe


Yep, only in the cases where the filamentary structure reveals itself:
https://www.googl...t=safari
Greenwood
5 / 5 (2) Aug 10, 2013
Yep, only in the cases where the filamentary structure reveals itself:


Ah, blind faith. You ignored what I said about plasma screening.
barakn
5 / 5 (3) Aug 10, 2013
EM obeys the longest range force laws, 1/r. -cantdrivel85

No, the force of an electrical point charge goes as 1/r^2. You're probably thinking of electrostatic potential energy. Once again your complete ignorance of physics is showing.


It's explained over here, from a paper presented at an IAU symposium;
http://adsabs.har...40..143P

When describing force laws, especially when comparing one force to another, one describes the force as it affects individual particles, and the electrostatic and gravitistatic forces certainly are 1/r^2 when described thusly. There certainly is a particular arrangement of electric charges that could lead to a 1/r field - an infinitely long line of evenly distributed charge, the infinite charged wire, if you will. However, there are no infinitely long charged wires that we know of.
barakn
5 / 5 (4) Aug 10, 2013
No matter how long a finite charged wire is, you could eventually move far enough away from it that the force changes from following a 1/r law to a 1/r^2 law. Also, there's no such thing as a charge smeared out in one dimension. If we zoom in on the wire far enough, we eventually discover that what appeared to be a line of charge is actually a line of charges. The charge is carried by a bunch of individual particles, and once we zoom in smaller than the average distance between particles, we notice that the electrical force, once again, goes as 1/r^2 around each one of those charged particles. The electrical force, no matter how contrived a situation you come with, will betray it's 1/r^2 nature. So pull up your pants, your ignorance is showing.
cantdrive85
1 / 5 (10) Aug 11, 2013
It's beyond the wire analogy, and no "infinite long" wire is needed, only a closed circuit, the Birkeland currents described in the article are pairs of parallel helical coaxial heteromac currents flowing through a highly dynamic plasma medium. As a matter of fact, the "wires" that make up these currents are most likely highly electrodynamic nanotubes/nanodust produced through plasma discharge.
http://www.plasma...S-06.pdf
http://arxiv.org/...2091.pdf
Lurker2358
1.8 / 5 (5) Aug 11, 2013
You can explain the ejection of gas from a pair of galaxies, in the presence of a third, larger galaxy, in the same way you can explain a larger planet ejecting a planetesmal from the solar system. The planetesmal get's thrown out, conservation of angular momentum says the planet gets a slight nudge inward.

Here, the planetesmal would be analogous to the gas stream.

The discrepancy in the models is probably because the models don't actually model realistic galaxies, there isn't a super computer with enough memory and processors. They model a few thousand point masses, and often don't even use proper vector sums of the gravity of all the objects.

There're other issues to consider, such as the population of massive stars. These gases have oxygen and sulfur, which speaks of one or more Supernovae. Oxygen and Sulfur are more massive, and would be closer to the parent star's core when it blows up, therefore they would have lower velocity when they escape, explaining why they lag behind..
Greenwood
5 / 5 (4) Aug 11, 2013
It's beyond the wire analogy, and no "infinite long" wire is needed, only a closed circuit, the Birkeland currents described in the article are pairs of parallel helical coaxial heteromac currents flowing through a highly dynamic plasma medium.


If you actually read the paper you will see the current in the filament is given by I = z*I(z) + theta*I(theta). That is an infinitely long helical wire. There is no end condition given so it is infinite.
cantdrive85
1 / 5 (8) Aug 11, 2013
There is no end condition given so it is infinite.


"So far as the theories of mathematics are about reality, they are not certain; so far as they are certain, they are not about reality." Einstein

"Mathematics is concerned only with the enumeration and comparison of relations." Carl Gauss

Anyway, proofs to convert to a finite circuit given here;
http://www.marmet...0246.pdf

Greenwood
5 / 5 (4) Aug 11, 2013
Anyway, proofs to convert to a finite circuit given here;


No, that's two infinitely long wires in opposite directions, which is not what is used in the above paper. It's more important to note it's a conversion not an equivalence, it does not guarantee the forces will remain unchanged. If you want to say 1/r forces arise from finite conductors, you have to show it does.
barakn
5 / 5 (3) Aug 11, 2013
And I might as well point that mass smeared out into an infinitely long wire will create a gravity field whose force decreases as 1/r. Why cantdrive85 brought this up is anyone's guess. It's mere mental masturbation.
cantdrive85
1 / 5 (5) Aug 11, 2013
My mistake, here is the accurate physics of what we are discussing, cosmical birkeland currents.
http://electric-c...elds.pdf
barakn
5 / 5 (3) Aug 12, 2013
No, we had moved beyond discussing that. You were trying to defend your claim that "EM obeys the longest range force laws, 1/r." You found a paper that shows a magnetic field decaying as 1/r^(1/2) instead, but it turns out this only occurs within the plasma. Outside of the plasma it will decay much faster. And I can outdo that easily. Imagine an infinite plane of mass with constant density. It turns out the force of gravity from this sheet has the same magnitude throughout the entire universe, i.e. it follows a 1/r^0 law. Try and top that.
Gmr
1 / 5 (2) Aug 12, 2013
Cue the out "well, all the universe IS plasma" in three... two...
cantdrive85
1 / 5 (6) Aug 12, 2013
From paper;
1. These magnetic fields stretch out much farther, and with greater potential effect, than previously thought. For large radial distances, the amplitude of those fields varies (slowly decays) as 1/√ r.
2. The helical structure of those fields is more complicated than previously thought. The angle of pitch of the helix increases smoothly and continuously with increasing radial distance, r, from the axis of the current.

"Another result is the finding that magnetic fields extend relatively farther from Birkeland currents than they would from a straight-line current."

The difference between your example and mine is reality, your example is without, mine is teeming with possibilities in this universe.
barakn
5 / 5 (3) Aug 13, 2013
The difference between your example and mine is reality, your example is without, mine is teeming with possibilities in this universe.
The infinite sheet is a good approximation for the force of gravity when close to a finite disk. It's actually easy undergraduate math - http://www.physic...t=122779 . That the force of gravity is almost constant with distance near a disk (and because of partially inelastic collisions) explains why Saturn's rings are so thin: http://burro.astr...ics.html . It is partially responsible for the structure of of the disk portion of spiral galaxies. There are even larger objects out there shaped like flat sheets where we could model gravity as a constant force with distance, at least when close enough: http://en.wikiped...eat_Wall . So my example is not just teeming with possibilities, it is teeming with actualities.
cantdrive85
1 / 5 (5) Aug 13, 2013
Imagine an infinite plane of mass with constant density.


That's my only option, is to imagine it because no such physical entity exists. Your example is merely mind games. Saturn's ring have little or nothing to do with gravity, Kristian Birkeland was able to replicate planetary rings using his "Terella" experiments. No such experiment has been shown to do the same with gravity. Saturn's rings are not "planes with constant density" and nor is a galactic plane. And without adding 95% more invisible stuff that only does exactly what it needs to do to support your theory, it is woefully incapable of describing the observed motions. It should also be noted, the "Great Wall" and other large structures are also not found in disc type structures but filamentary web-like and cellular structures. All the morphologies one would expect from plasma.