Cosmic collisions: SOFIA unravels the mysterious formation of star clusters

November 7, 2018, NASA
Illustration of a star cluster forming from the collision of turbulent molecular clouds, which appear as dark shadows in front of the background galactic star field. Credit: NASA/SOFIA/Lynette Cook

The sun, like all stars, was born in a giant cold cloud of molecular gas and dust. It may have had dozens or even hundreds of stellar siblings – a star cluster – but these early companions are now scattered throughout our Milky Way galaxy. Although the remnants of this particular creation event have long since dispersed, the process of star birth continues today within our galaxy and beyond. Star clusters are conceived in the hearts of optically dark clouds where the early phases of formation have historically been hidden from view. But these cold, dusty clouds shine brightly in the infrared, so telescopes like the Stratospheric Observatory for Infrared Astronomy, SOFIA, can begin to reveal these long-held secrets.

Traditional models claim that the force of gravity may be solely responsible for the formation of stars and . More recent observations suggest that magnetic fields, turbulence, or both are also involved and may even dominate the creation process. But just what triggers the events that lead to the formation of star clusters?

Astronomers using SOFIA's instrument, the German Receiver for Astronomy at Terahertz Frequencies, known as GREAT, have found new evidence that star clusters form through collisions between .

The results were published in the Monthly Notices of the Royal Astronomical Society.

"Stars are powered by nuclear reactions that create new chemical elements," said Thomas Bisbas, a postdoctoral researcher at the University of Virginia, Charlottesville, Virginia, and the lead author on the paper describing these new results. "The very existence of life on earth is the product of a star that exploded billions of years ago, but we still don't know how these stars—including our own sun—form."

Illustration of the molecular clouds surrounded by atomic envelopes, in green, which have been detected by SOFIA via emission from ionized carbon. The spatial offset and motions of these envelopes confirm predictions of simulations of cloud collisions. Credit: NASA/SOFIA/Lynette Cook

Researchers studied the distribution and motion of ionized carbon around a molecular cloud where can form. There appear to be two distinct components of colliding with each other at speeds of more than 20,000 miles per hour. The distribution and velocity of the molecular and ionized gases are consistent with simulations of cloud collisions, which indicate that star clusters form as the gas is compressed in the shock wave created as the clouds collide.

"These star formation models are difficult to assess observationally," said Jonathan Tan, a professor at Chalmers University of Technology in Gothenburg, Sweden, and the University of Virginia, and a lead researcher on the paper. "We're at a fascinating point in the project, where the data we are getting with SOFIA can really test the simulations."

While there is not yet scientific consensus on the mechanism responsible for driving the creation of star clusters, these SOFIA observations have helped scientists take an important step toward unraveling the mystery. This field of research remains an active one, and these data provide crucial evidence in favor of the collision model. The authors expect future observations will test this scenario to determine if the process of cloud collisions is unique to this region, more widespread, or even a universal mechanism for the formation of star clusters.

"Our next step is to use SOFIA to observe a larger number of molecular that are forming star clusters," added Tan. "Only then can we understand how common cloud collisions are for triggering in our galaxy."

SOFIA is a Boeing 747SP jetliner modified to carry a 106-inch diameter telescope.

Explore further: Magellanic clouds duo may have been a trio

More information: Thomas G Bisbas et al. The inception of star cluster formation revealed by [C ii] emission around an Infrared Dark Cloud, Monthly Notices of the Royal Astronomical Society: Letters (2018). DOI: 10.1093/mnrasl/sly039

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America3D
1 / 5 (4) Nov 07, 2018
see my 3D SPACE rocket launch (fan art) please youtu.be/APHJFWW2tqU
Buddyroe
2 / 5 (2) Nov 07, 2018
I would think that gravity and clumping in very long periods of time creates. Much like planets.
rrwillsj
3 / 5 (2) Nov 07, 2018
Br, what I take from this article is that there are different processes occurring. Some of them successfully result in stars & maybe planets.

The random cussedness of reality being a bedlam of unreliable cause & effect will result in a multitude of possible outcomes.

I suspect that eventually, there will be two varieties of Stellar objects. The beloved listing of nice, neat categories of Star types. Maybe a hundred or more major categories, with hundreds of sub-categories & linked variations.

And a much hated HUGE! collection of outlier stars & indeterminate objects. That rudely refuse to fit in any of the vaunted nice, neat boxes that are beloved of Human egotism.

This petty-human self-absorption arising out of tens of millions of years of monkey survival instincts. Loudly proclaiming our demands at the Universe.

Yeah? No... I get the impression that the Cosmos remains unimpressed.
Old_C_Code
2.6 / 5 (5) Nov 07, 2018
More recent observations suggest that magnetic fields, turbulence, or both are also involved and may even dominate the creation process.


This is a surprising and significant statement for the gravity only mainstream.
cantdrive85
1.5 / 5 (8) Nov 07, 2018
There are a number of plasma processes that are ubiquitous in plasmas and are relevant to the above paper, but nary a mention of them. First, Marklund convection. It is what is separating the Cii from the rest of the "cloud". Which is separated by (B) double layers and not shocks. IiI, critical ionization velocity, certainly relevant given the velocity of this ionized current. And lastly, the magnetic pinch effect. This is the only legitimate process that creates the forces necessary to create stars in these "magnetic clouds". Like Alfvén said;
"Students using astrophysical textbooks remain essentially ignorant of even the existence of plasma concepts, despite the fact that some of them have been known for half a century...."

RealityCheck
2.3 / 5 (6) Nov 08, 2018
@Old_C_Code
@cantdrive85.
@jonesdave
@et al.

All 'sides' will no doubt recall what I have long and often pointed-out: the HYBRID FORCES evolutionary trajectory for all these phenomena/features.

Above study merely confirms that at DIFFUSE gas/dust/plasma 'cloud' stages, the E-M forces prevail/dominate, to start off the relatively smaller mass-energy aggregating/structuring processes/features. Up until the concentration of mass-energy by E-M action is sufficiently large that GRAVITY begins to play a significantly role, introducing/anchoring HYBRID 'feedback' E-M/Grav dynamics which further accelerate aggregating/structuring processes/features. Then, once cumulative gravity effect is strong/dominant enough, the mass-energy concentration becomes a fully-fledged gravitatinal system of its own, with its own behavior/effects that can eventually re-arrange/dominate over E-M forces/dynamics; eventually leading to degeneracy states of quark-gluon plasma as in NSs and BHs bodies. :)
gculpex
1 / 5 (2) Nov 08, 2018
Above study merely confirms that at DIFFUSE gas/dust/plasma 'cloud' stages, the E-M forces prevail/dominate, to start off the relatively smaller mass-energy aggregating/structuring processes/features. Up until the concentration of mass-energy by E-M action is sufficiently large that GRAVITY begins to play a significantly role, introducing/anchoring HYBRID 'feedback' E-M/Grav dynamics which further accelerate aggregating/structuring processes/features. Then, once cumulative gravity effect is strong/dominant enough, the mass-energy concentration becomes a fully-fledged gravitatinal system of its own, with its own behavior/effects that can eventually re-arrange/dominate over E-M forces/dynamics; eventually leading to degeneracy states of quark-gluon plasma as in NSs and BHs bodies. :)

But is there enough energy for raising the temperature to ignite fusion?
RealityCheck
2.3 / 5 (6) Nov 08, 2018
@gculpex.
But is there enough energy for raising the temperature to ignite fusion?
I previously pointed out that once a stellar-mass/energy concentration is reached, the gravitational compression-heating (think of diesel compression-heating process) adds up because of the efficient heat/energy-loss LAG effect of the plasma material itself. The temps soar and fusion is eventually triggered. And because of the turbulent convection/streaming etc inherent in such contained plasmas (think of fusion power plants), there may also be distributed fusion events due to plasmoid 'magnetic self compression' processes/events (think of the Focus Fusion system) at all levels of the star, which would also add further to turbulence/fusion temps/triggers possibilities. Ok? :)
cantdrive85
2.3 / 5 (6) Nov 08, 2018
Ok? :(

That is quite the nonsensical collection of words. A sort of HYBRID type of reality which combines a 'feedback' of dynamics.
Steelwolf
1 / 5 (2) Nov 09, 2018
@RC and Gulpex, with the increased friction and turbulence you will have added electrical disequilibrium which will continually try to re-establish equilibrium, this will often lead to arcing, sparks and current induced heating such as we see with lightning all the time here on Earth.

When you have a dense enough mass of gas/matter collapsing it WILL create a differentiated charge that WILL equalize in some form, and so there is an added heat source for any ignition event at solar levels. Continued turbulence means continued differential charges and, for a time, one can extrapolate a high charge environment working to equalize will, along with pressure and mass, increase the materials temperatures beyond what just pressure can do.
jonesdave
3.7 / 5 (6) Nov 09, 2018
There are a number of plasma processes that are ubiquitous in plasmas and are relevant to the above paper, but nary a mention of them. First, Marklund convection. It is what is separating the Cii from the rest of the "cloud". Which is separated by (B) double layers and not shocks. IiI, critical ionization velocity, certainly relevant given the velocity of this ionized current. And lastly, the magnetic pinch effect. This is the only legitimate process that creates the forces necessary to create stars in these "magnetic clouds". Like Alfvén said;
"Students using astrophysical textbooks remain essentially ignorant of even the existence of plasma concepts, despite the fact that some of them have been known for half a century...."



Nope, you just made that up.
cantdrive85
1.7 / 5 (6) Nov 09, 2018
You heard it here, jonesdumb believes Marklund convection, double layers, CIV, and the magnetic pinch effect are just "made up". LOL!
jonesdave
3 / 5 (4) Nov 09, 2018
You heard it here, jonesdumb believes Marklund convection, double layers, CIV, and the magnetic pinch effect are just "made up". LOL!


No, you cretin, I do not see them in this paper, you idiot. That is what you made up.
cantdrive85
3 / 5 (4) Nov 09, 2018
I do not see them in this paper,

Comprehension is not your strong point, although this has already been established. You obviously didn't understand where I explicitly stated;
", but nary a mention of them...."
It was actually the point of the comment that they mentioned a bunch of irrelevant non-plasma physics to explain this plasma.
granville583762
4 / 5 (4) Nov 09, 2018
Except solar fusion depends on the rising and falling plasma electric fields, generating infinitely greater magnetic fields that superconductors can only dream of!
phys.org> Traditional models claim that the force of gravity is responsible for stars formation recent observations suggest magnetic fields, turbulence dominate the creation process.

ITER, without magnetic fields is doomed
Fusion is totally dependant on electric fields and magnetic fields
Oh, and of course the neutron
Otherwise the proton cannot get past the coloumb barrier
We all know who
The nuclear
Tactician
The expert
Who
No one can fail to miss
As he all ways
announces
His appearance
because
When he appears
We suddenly
From being
The average Joe
To sanitise JDs vocabulary
We become
We all become cretins
As JD so succinctly
Describes us
Because
In JDs world of fusion
Only head banging is the true cause of fusion
jonesdave
2.3 / 5 (3) Nov 09, 2018
I do not see them in this paper,

Comprehension is not your strong point, although this has already been established. You obviously didn't understand where I explicitly stated;
", but nary a mention of them...."
It was actually the point of the comment that they mentioned a bunch of irrelevant non-plasma physics to explain this plasma.


Why would they mention them????? This is about enormous colliding clouds. They are looking at large scale effects. The putative effects you mentioned are irrelevant on the scales they are looking at.
rrwillsj
2 / 5 (4) Nov 13, 2018
When one considers the childish tantrums from the electricwoocult & plasma-fakirs & aethernuts playpen?

Gravity remains "attractive", serenely ignoring the insignificant EM, WM. SN forces on the Cosmic scales.

This is why they get their pantaloons in such a twist. They can pretend they are controling something when they get two magnets to repel one another. Or spark a neon light.

Gravity refuses to obey their ravings. Just keeps on doing what it does in complete disregard of their fabulist demands.

That is why they hate it & ignore all the evidence that proves it predominance.

This is a psychological problem. Nothing to do with Physics or Cosmology or Astronomy. And everything to do with their bruised egotism and feelings of inadequacy to the Modern Age.
Steelwolf
3.7 / 5 (3) Nov 14, 2018
So, articles like this about major galactic tails from ram-stripping showing magnetic fields acting to restrict size and actually help small star formation: https://arxiv.org...4916.pdf

Or perhaps this one: https://arxiv.org...4401.pdf

It is certainly not all 'woo', it is mainstream science that you merely do not understand and yet these people have published articles on what I have been positing here for over a decade.

Major takeaway from these studies is as we gain better ability to detect them, we are finding more magnetic fields and/or things that can only have been done earlier by magnetic fields or electricity itself, that we see only the remains of now. We are finding more mechanisms for creating and amplifying these magnetic fields as well. And there is nothing 'woo' about it. Basic theories backed by math AND Observation.
theredpill
4 / 5 (4) Nov 14, 2018
"It is certainly not all 'woo',"

Not if you have the capacity for logical thought.

" it is mainstream science that you merely do not understand and yet these people have published articles on what I have been positing here for over a decade."

The mainstream science above is not the theoretical branch, therefore some of the commenters above are out of their element because we are dealing with real physics. Read the entire post from rrwillsj....the guy actually thinks gravity can dominate over EM forces on the same scale. So he starts off wrong and goes full throttle into babbling idiot. Must be a Jones or ojorf "protégé". ( One must put that word in quotes due to it's definition, in this case the guidance part is correct but the rest of the definition is pretty much the opposite)

Read more at: https://phys.org/...html#jCp
cantdrive85
1 / 5 (1) Nov 14, 2018
Why would they mention them?????

You're right, why would they bother with plasma physics to describe this plasma when they can use the irrelevant maths based claptrap.

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