Star-forming filaments

May 22, 2017, Harvard-Smithsonian Center for Astrophysics
A false-color image map of the gas density in the Musca star-forming filament (the highest densities are shown in red). New theoretical work on the structure of these long filaments proposes several kinds of star-forming zones along the length and successfully reproduces many of the features seen in filaments like this one in Musca. Credit: Kainulainen, 2016

Interstellar molecular clouds are often seen to be elongated and "filamentary" in shape, and come in a wide range of sizes. In molecular clouds, where stars form, the filamentary structure is thought to play an important role in star formation as the matter collapses to form protostars. Filamentary clouds are detected because the dust they contain obscures the optical light of background stars while emitting at infrared and submillimeter wavelengths.

Observations of some filaments indicate that they are themselves composed of bundles of closely spaced fibers with distinct physical properties. Computer simulations are able to reproduce some of these filamentary structures, and astronomers generally agree that turbulence in the gas combined with gravitational collapse can lead to filaments and protostars within them, but the exact ways in which filaments form, make , and finally dissipate are not understood. The number of new stars that develop, for example, varies widely between filaments for reasons that are not known.

The usual model for a star forming filament is a cylinder whose density increases towards the axis according to a specific , but which otherwise is uniform along its length. CfA astronomer Phil Myers has developed a variant of this model in which the filament has a star-forming zone along its length where the density and diameter are higher, with three generic profiles to describe their shapes. Besides being a more realistic description of a filament's structure, the different density profiles develop different strength gravitational "wells" naturally leading to different numbers of stars forming within them.

Myers compares the properties of these three kinds of zones with the properties of observed star formation filaments, with excellent results. The filament in the molecular cloud in Musca has relatively little star formation, and can be reasonably well explained with one of the three profiles indicative of an early stage of evolution. A small cluster of young stars in the Corona Australis constellation fits a second model that has evolved for longer, while Ophiuchus hosts a that may be near the end of its star forming lifetime and resembles the third type. The three profiles so far seem able to account for the full range of conditions. The new results are an important step in bringing more sophistication and realism to the theory of star forming filaments. Future work will probe the specific processes that fragment the various star-forming zones into their stars.

Explore further: The lifetimes of massive star-forming regions

More information: Philip C. Myers. Star-forming Filament Models, The Astrophysical Journal (2017). DOI: 10.3847/1538-4357/aa5fa8

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SlartiBartfast
3.1 / 5 (18) May 22, 2017
Cue the EU zealots in 3...2...1...
Benni
2.3 / 5 (15) May 22, 2017
Cue the DM zealots in 3....2...1....
rossim22
2.5 / 5 (21) May 22, 2017
Why imagine or believe that gravitational collapse plus turbulence of gas (in a vacuum..?) creates the filamentary structure when we KNOW that plasma already behaves this way on its own? Occam's razor shows that electromagnetically confining this charged dust and gas is a better theory than trying to model turbulence (again.. in a vacuum..?) with gravitational collapse to explain the formation of filaments.

Filaments made of filaments, as this article states, is ubiquitous and predicted in an EU-minded paradigm.
cantdrive85
2.9 / 5 (19) May 22, 2017
Computer simulations are able to reproduce some of these filamentary structures, and astronomers generally agree that turbulence in the gas combined with gravitational collapse can lead to filaments and protostars within them, but the exact ways in which filaments form, make stars, and finally dissipate are not understood.

This is because astrophysicists are plasma ignoramuses which insist on treating this plasma as a gas and ignore the immensely more powerful than gravity, EM forces to describe these phenomena. Is it any wonder the plasma ignoramuses require 84% more invisible faerie dust to make it work when the longest/strongest force laws of EM are ignored?
rossim22
2.3 / 5 (12) May 22, 2017

Is it any wonder the plasma ignoramuses require 84% more invisible faerie dust to make it work when the longest/strongest force laws of EM are ignored?


I wouldn't say the forces are ignored... that gives ammo to the mainstream supporters whom believe us EU supporters think some conspiracy is involved. There is no conspiracy, plasma cosmology is NOT a conspiracy theory.

The problem is that mainstream scientists think nothing is wrong with their model. They've normalised their bias, they don't even see it anymore. We have never directly observed gravitational collapse + turbulence form a filament, which is why it's left to models.

However, we have observed charged dust and plasma form filaments in the lab countless times. Based on Occam's Razor alone, the hypothesis which makes the same prediction (filaments) but which requires fewer assumptions (turbulence (in a vacuum?)+ gravitational collapse compared to no new physics) should be given further investigation.
Solon
1 / 5 (9) May 22, 2017
Here I must disagree with both EU and the gravitational collapse and turbulence models. EU is closer, except that what is being formed in the filaments are not stars but planetary bodies, regular and irregular shapes, as the result of the condensing of multi-layer Coulomb crystals. Spheres, which are hollow, form preferentially at 40-50,000 degrees, which is why they are identified as hot young stars. Coulomb crystals can form in linear or toroidal plasma flux tubes.
Chris_Reeve
May 22, 2017
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691Boat
4.6 / 5 (9) May 22, 2017
The reporting -- and one presumes the original paper, from which it came -- makes no mention that plasma scaling could explain the observation with off-the-shelf laboratory observations.


Wow, they have created plasma filaments in the lab that make little tiny stars? That's impressive! You have a link to that?
Chris_Reeve
May 22, 2017
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691Boat
4.6 / 5 (9) May 22, 2017
so you are saying that making a plasma filament in a lab is directly equivalent to these star forming filaments? That is very impressive.
I know that fission of Uranium releases neutrons, and has been demonstrated in labs around the world. Does this mean that every neutron in existence is from fission of Uranium?
HannesAlfven
1.4 / 5 (9) May 22, 2017
Re: "so you are saying that making a plasma filament in a lab is directly equivalent to these star forming filaments?"

The closest equivalent from the set of phenomena we're more familiar with here on Earth is the production of ball lightning along branching terrestrial lightning. The correct geometry is all there -- which should matter to more than than it apparently does.

Achieving "distinct physical properties" for each of these cosmic "fibers" requires two simultaneous phenomena: both a long-range attraction and a short-range repulsion. There are not many phenomena which exhibit such geometry -- certainly not the radial attractive force of gravity.

There honestly shouldn't be any ideology at play here. The geometric observations by themselves should sufficiently constrain the inferences for the mainstream to already understand that they have made a huge mistake here.
691Boat
4.6 / 5 (11) May 22, 2017
I have been told in these forums that the voltage differential in the plasmas in our own solar system and galaxy is too small to measure by our instruments. Last I knew, lightning was on the order of 100's or 1,000's of kV differential and carried thousand of amperes of current. That is a whole lot of energy being transferred over a very short period of time. What are the voltage differentials and currents being passed through your space plasma filament?
And I will ask again, what is the sink for these huge plasma filaments?
HannesAlfven
1.4 / 5 (9) May 22, 2017
691Boat, this might help a little bit. Comes from Jim Weninger ...

"If all these monstrous currents are indeed out there, where are all the required equally monstrous azimuthal magnetic fields? Wherever we look, Faraday rotation measurements always demonstrate that such magnetic fields are not there. No significant azimuthal component of magnetic fields around a filamentary structure, no currents." Q.E.D., gravity wins.

For example, in a patently obvious electromagnetic filament like the Double Helix Nebula, if astronomers had measured a magnetic field which wrapped around it in one azimuthal direction, maybe it would have been much harder for them to ignore its electrical nature. But that's not how electric currents in a minimum energy configuration behave in a plasma ...

(cont'd)
HannesAlfven
1.4 / 5 (9) May 22, 2017
(cont'd)

As the Lundquist-Scott model demands, a Birkeland Current has a tight radial structure of alternate winding and unwinding magnetic fields. If you visualize for a moment how the magnetic field vectors continually rotate with increasing radial distance, you will realize that, no matter the angle from which you observe the filament, the azimuthal component of the magnetic field always gets almost completely cancelled out, leaving only the background magnetic field in which the field-aligned filament flows.

What that obviously means is that great care should be taken when conjecturing the strength of these currents, because the conventional ways of observing these magnetic fields might lead to erroneous values which are far below actual values.
RealityCheck
2.1 / 5 (7) May 22, 2017
@691Boat, @cantdrive, @HannesAlfven.

Again I remind you that more than one cause/force starts the hybrid processes/motions which at some stage include streaming/filamentary 'bundling/separations' etc etc which any lab or cosmic filament/stream can develop over time scales applicable in lab/cosmic contexts.

@691Boat especially, re your response to @Chris_Reeve:
Wow, they have created plasma filaments in the lab that make little tiny stars? That's impressive! You have a link to that?
Your jesting/sarcastic tone may be inappropriate once you read up on lab "Plasma Focus Devices" which use the self-concentrating/pinching/attraction effect of plasma streams to evolve PLASMOID process/object which can magnify LOW input energies to many orders of magnitude HIGHER energies in said 'plasmoid' features; which then explode. And HannesAlfven also mentioned the 'ball lightning' features as well. So one may 'analogize' plasmoid/ball-lighting as transient/small-scale 'stars'? :)
HannesAlfven
1 / 5 (7) May 22, 2017
Re: "Again I remind you that more than one cause/force starts the hybrid processes/motions which at some stage include streaming/filamentary 'bundling/separations' etc etc which any lab or cosmic filament/stream can develop over time scales applicable in lab/cosmic contexts."

I'm not so sure that gravity will play much of a role in the early phases. The filamentation seems to suggest a transient event which subsequently subsides.
Da Schneib
5 / 5 (6) May 22, 2017
To be able to predict which filaments will produce stars, and from that figure out what kinds of structures will produce more stars and what kinds less, will be interesting to say the least. More grist for the star formation simulation mills.
Steelwolf
1 / 5 (3) May 23, 2017
The article concerning the 'new' attractive force of blackbody objects ( https://phys.org/...ogy.html )and how it pertains most especially to dust particles it may well be that between the blackbody force, magnetism and gravity, in combination, with electromagnetism first aligning a cloud of plasma, gas and dust particles, the blackbody force helping to draw them together and once close enough, gravity can further condense the dust into nodes which can become anything from planetisimals to planets, brown dwarfs and stars of all stripes.
HannesAlfven
1 / 5 (6) May 23, 2017
Steelwolf, plasma physics is an observationally-driven science. It's rare that theorists have successfully sat a desk and imagined how the plasma behaves. If the science journalism was actually functioning, this lesson would have been learned a long time ago.
691Boat
5 / 5 (9) May 23, 2017
@RC
HannesAlfven also mentioned the 'ball lightning' features as well. So one may 'analogize' plasmoid/ball-lighting as transient/small-scale 'stars'? :)


"transient star", eh? Doesn't add up to me.... So we have an electric current that we have never measured passing through space, generating a plasma from the Hydrogen that is present, but already in a dense community for some reason OTHER than gravity. got it. This magic electric then current 'converts' the Hydrogen clouds to plasma which by definition is ionized, so in Hydrogen, you get a proton and an electron. This plasma then gets denser and denser through self focusing, ignoring the fact that all these like charges repel each other through the EM force which is much stronger than gravity, to the point that enough has "plasmoidally" condensed to form a star. Did I miss anything?
cantdrive85
2 / 5 (4) May 23, 2017
Did I miss anything?

Yep, intelligence and a clue.
cantdrive85
1.8 / 5 (5) May 23, 2017
So we have an electric current that we have never measured passing through space

There have been numerous electric currents measured in space, but alas your wilful ignorance will preclude this knowledge. When the applicable probes reach these currents 30ly away we will be able to "prove" this hypothesis. Until then we may have to rely upon our knowledge of plasmas derived in the laboratory. Or we can rely on thought experiments of the plasma ignoramuses as you would demand.
691Boat
4.6 / 5 (10) May 23, 2017
So we have an electric current that we have never measured passing through space

There have been numerous electric currents measured in space, but alas your wilful ignorance will preclude this knowledge. When the applicable probes reach these currents 30ly away we will be able to "prove" this hypothesis. Until then we may have to rely upon our knowledge of plasmas derived in the laboratory. Or we can rely on thought experiments of the plasma ignoramuses as you would demand.

Can you link me to some peer reviewed findings of these numerous currents? All I have seen is links to EU sites and one measurement 2+billion ly away emanating from a possible black hole. You'd think these currents would be so much easier to find since the entire universe is powered by them!
Chris_Reeve
May 23, 2017
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Chris_Reeve
May 23, 2017
This comment has been removed by a moderator.
Chris_Reeve
May 23, 2017
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RealityCheck
1 / 5 (4) May 23, 2017
@691Boat.

DISCLAIMER: From my 'reminder to you/other posters above, you can see I am NOT in any 'either-or' (ie, GRAVITY-or-EM) 'camp'; but always point out the complex/hybrid nature of the such feature's nature/evolutionary history.

BEFORE READING FURTHER, please 'mute' your 'kneejerk reaction' from reading bias/longstanding preconceptions; at least enough to actually read/understand OBJECTIVELY and consider CALMLY what MAINSTREAM astronomy has ALREADY discovered/acknowledged. :)

- Most of space Hydrogen etc is charged/ionized PLASMIC material to SOME degree.

- There are 'plasmic' material CURRENTS/STREAMS/SWIRLS etc in space due to Gravitational AND Electric AND Magnetic FIELDS DYNAMICS flow-structures/forces/effects acting over eons across all of LOW-GRAVITATION and LOW-flow-resistance strength 'free' space. OK?

- Once self-organized structures reach stellar mass, Gravity EXTENDS 'lifetime' of a feature which started as a PLASMIC 'concentration'.

Carry on, mate. :)
Chris_Reeve
May 23, 2017
This comment has been removed by a moderator.
Steelwolf
1 / 5 (3) May 23, 2017
@691 Boat, For an article that links the electromagnetic and gravitic forces in stellar formation:

https://phys.org/...tml#nRlv

And all one need do is remember that magnetic fields arise from electrical moment and that where there is electricity there is magnetic field, and where there is a magnetic field there is electricity or a charge flow or charge disequilibrium in either case. And, this is a slim slice through the available literature on the subject, just articles from here even.
Chris_Reeve
May 23, 2017
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cantdrive85
1 / 5 (4) May 24, 2017
The Marklund convection, to my knowledge has not been observed in a Birkeland current

Your wilful ignorance of that which you claim to study is pathetic, it's even in wiki;
Professor Emeritus of the Alfvén Laboratory in Sweden, Carl-Gunne Fälthammar wrote:[6] "A reason why Birkeland currents are particularly interesting is that, in the plasma forced to carry them, they cause a number of plasma physical processes to occur (waves, instabilities, fine structure formation). These in turn lead to consequences such as acceleration of charged particles, both positive and negative, and element separation (such as preferential ejection of oxygen ions). Both of these classes of phenomena should have a general astrophysical interest far beyond that of understanding the space environment of our own Earth."
https://en.m.wiki..._current
Note: "the preferential ejection of ions" is the result of the Marklund convection.
cantdrive85
1 / 5 (3) May 24, 2017
Actually, I was responding to YOUR sweeping assumptions about these filaments:

Once again your ignorance preceeds you, CR is refering to the volumes of data, lab experiments, and theory developed over the last century regarding these ubiquitous plasma phenomena. You know, science.
cantdrive85
1 / 5 (3) May 24, 2017
Oops! Missed a word;
Note: "the preferential ejection of ^oxygen^ ions" is the result of the Marklund convection.
cantdrive85
1 / 5 (3) May 24, 2017
The magic bowls must be how the oxygen is preferentially separated.
cantdrive85
1 / 5 (3) May 24, 2017
The interaction of electric charges is magic in your mind? That would explain your eagerness to accept the magic bowl guess.
Steelwolf
1 / 5 (1) May 24, 2017
Seeing as how all normal matter is made of combinations of charged particles and plasma is merely disassociated atoms so that there is separated positive and electric charge inherent within any cloud of plasma, generally the temperature being too high for them to easily recombine. Since this is a Univeral process, one can therefore readily expect there to be differentially charged regions all through space as we know it, and so there Will be electric current flows with the attendant magnetic fields. Since we are now finding these magnetic fields up to several hundred lightyears across, it is becoming really ridiculous to keep denying that electromagnetism has some acting force on the materials in question since it is of an ubiquitous enough occurrence as to be a major contribution towards shaping our universe, ESPECIALLY if there was a big bang and the universe was at one time more compact, the EM effects would have had more severe consequence due to the denser state.
yep
1 / 5 (3) May 25, 2017

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