On the generation of solar spicules and Alfvenic waves

On the generation of solar spicules and Alfvenic waves
In the image obtained with the NASA's spectrograph IRIS, can be seen in the bedge or limbo of the Sun the multitude of jets leaping the surface. In the center image, the numerical model is able to reproduce the jets. In the image below, taken with the Swedish Solar Telescope of the Roque de los Muchachos Observatory (La Palma), the jets are observed in the solar disk as filamentous structures of short duration and reflected in the spectrum shifted to blue because they are getting close to the Earth. Credit: Swedish Solar Telescope of the Roque de los Muchachos Observatory (La Palma)

Combining computer observations and simulations, a new model shows that the presence of neutrals in the gas facilitates the magnetic fields to penetrate through the surface of the Sun producing the spicules. In this study, led by an astrophysicist who studied at the University of La Laguna, participated the Swedish Solar Telescope of the Roque de los Muchachos Observatory in La Palma.

At any given moment, as many as 10 million wild snakes of solar material leap from the sun's surface. These are spicules, and despite their abundance, scientists didn't understand how these jets of plasma form nor did they influence the heating of the outer layers of the sun's atmosphere or the . Now, for the first time, in a study partly funded by NASA, scientists have modeled spicule formation. For the first time, a scientific team has revealed their nature by combining simulations and images taken with the NASA's IRIS spectrograph and the Swedish Solar Telescope of the Roque de los Muchachos Observatory (Garafía, La Palma). The study, led by Dr. Juan Martinez-Sykora, researcher at Lockheed Martin's Solar and Astrophysics Laboratory (California) and astrophysicist at the University of La Laguna (ULL), is published today in the journal Science.

The observations were made with IRIS (NASA's Interface Region Imaging Spectrograph), a 20 cm ultraviolet space telescope with a spectrograph able to observe details of about 240 km, and the Swedish Solar Telescope, located at the Roque de los Muchachos Observatory. This spacecraft and the ground-based telescope study the lower layers of the solar atmosphere, where the spicules form: chromosphere and the region of transition

In addition to the images, they used computer simulations whose code was developed for almost a decade. "In our research," says Prof. Bart De Pontieu, also author of the study, "both go hand in hand. "We compare observations and models to figure out how well our models are performing, as well as how we should interpret our space-based observations."

Their is based in the dynamics of plasma—the hot gas of charged particles that streams along magnetic fields and constitutes the sun. Earlier versions of the model treated the interface region as a uniform, or completely charged, plasma, but the scientists knew something was missing because they never saw spicules in the simulations.

The model they generated is based on plasma dynamics, a very hot partially ionized gas flowing along the magnetic fields. Previous versions considered the lower atmosphere to be a uniform or fully charged plasma, but they suspected something was missing since they never detected spikes in the simulations.

The key, the scientists realized, was neutral particles. They were inspired by Earth's own ionosphere, a region of the upper atmosphere where interactions between neutral and charged particles are responsible for numerous dynamic processes. In cooler regions of the sun, such as the interface region, plasma isn't actually uniform. Some particles are still neutral, and neutral particles aren't subject to magnetic fields like charged particles are. Scientists based previous models on a uniform plasma in order to simplify the problem—modeling is computationally expensive, and the final model took roughly a year to run with NASA's supercomputing resources—but they realized neutral particles are a necessary piece of the puzzle.

"Usually magnetic fields are tightly coupled to charged particles," said Juan Martínez-Sykora, lead author of the study and a solar physicist at Lockheed Martin. "With only charged particles in the model, the magnetic fields were stuck, and couldn't rise to the surface. When we added neutrals, the magnetic fields could move more freely."

Neutral particles facilitate the buoyancy the marled knots of magnetic energy need to rise through the boiling plasma and reach the surface. There, they snap producing spicules, releasing both plasma and energy. The simulations closely matched the observations; spicules occurred naturally and frequently.

"This result is a clear example of the breakthrough that can be achieved by combining powerful theoretical-numerical methods, state-of-the-art observations and supercomputing tools to better understand astrophysical phenomena", explains Prof.Fernando Moreno-Insertis, solar physicist at IAC, Professor ar the ULL and supervisor of the work Diploma of Advanced Studies (DEA) of Juan Martínez-Sykora. "The great complexity of many of the phenomena that occur in the solar atmosphere forces us to consider at the same time the dynamics of partially ionized gas, the and the radiation-matter interaction in order to be able to explain them satisfactorily".

"This result is a clear example of the breakthroughs that can be achieved by combining powerful theoretical-numerical methods, state-of-the-art observations and supercomputing tools to better understand astrophysical phenomena", explains Fernando Moreno-Insertis, solar physicist at IAC, Professor at the ULL and supervisor of the DEA thesis (equivalent to a master´s thesis) of Juan Martínez-Sykora. "The great complexity of many of the phenomena that occur in the solar atmosphere forces us to consider at the same time the dynamics of partially ionized gas, the magnetic field and the radiation-matter interaction in order to be able to explain them satisfactorily".

The scientists' updated model revealed something about solar energy transport as well. It turns out the energy in this whip-like process is high enough to generate Alfvén waves, a strong kind of wave scientists suspect is key to heating the sun's atmosphere and propelling the solar wind, which constantly bathes the solar system with charged from the sun.

The National Academy of Sciences awarded Prof. Mats Carlsson and Prof. Viggo H. Hansteen, both developers of the model and authors of the study, with the 2017 Arctowski Medal in recognition of their contributions to the study of solar physics and the sun-Earth connection. Juan Martínez-Sykora included the effects produced by the presence of the .


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Scientists uncover origins of the Sun's swirling spicules

More information: J. Martínez-Sykora et al, On the generation of solar spicules and Alfvénic waves, Science (2017). DOI: 10.1126/science.aah5412
Journal information: Science

Provided by Instituto de Astrofísica de Canarias
Citation: On the generation of solar spicules and Alfvenic waves (2017, October 13) retrieved 27 May 2019 from https://phys.org/news/2017-10-solar-spicules-alfvenic.html
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Oct 13, 2017
So, what this article is telling us: Astronomers do, in fact, know that plasma exists, do study plasmas, and model plasmas. They are even aware of the mythical "Alfven" that the EU cranks are always going on about. Can we finally say that this plugs the holes in the EU "arguments" about how astronomy operates? Maybe it doesn't answer all of their (ill-informed) questions about why EU is not considered a reasonable explanation of observed phenomena; but can we at least agree that the next time they try to attack Astronomers or the study of astronomy, that those attacks are obviously unfounded?

Oct 13, 2017
s, thank you for a reasonable and rational discussion of differing viewpoints between contentious commentators.

As for me? I enjoy incoherent rants and incomprehensible renderings of text plagiarized from obsolete textbooks and babbling biblical buffoonery.

Though I still don't understand the claim that craters are caused by lightning strikes? Thundering in a vacuum? I've heard of people hearing voices in their head but thunderclaps from outer space?

Oct 13, 2017
can we at least agree that the next time they try to attack Astronomers or the study of astronomy, that those attacks are obviously unfounded?
@Shavera
LOL
doubtful, especially considering they will use a singular advocate as demonstrative of ignorance for the astrophysical community as a whole while then quoting said same person's electrical engineering study in another thread and claiming engineers know more than astrophysicists
(ask CD about that one! LMFAO)

and next, in thins thread - the PO site will allow chris/hannes to flood with gish gallop while rc posts irrelevant nonsensical texts about how correct he is regarding modern astrophysics

Oct 13, 2017
@Captain Stumpy.
and next, in thins thread - the PO site will allow chris/hannes to flood with gish gallop while rc posts irrelevant nonsensical texts about how correct he is regarding modern astrophysics
Why childishly 'personalize' things again by trying to sneak in a demonstrable lie like that,mate? Have you no shame or sense, CS? Lower case "rc" doesn't somehow 'protect' you or absolve you of being held accountable for for your obvious lie. The record will show I am INDEPENDENT and have objectively used known/evolving mainstream science/logics to correct/ remind/ caution etc ALL 'sides' in discussion of Plasma phenomena/issues, irrespective of whether they were Plasma Universe, Electric Universe or OTHER 'factions'. Particularly I have pointed out that all cosmic phenomena is HYBRID process involving more than one factor/force interacting/feedbacking over long temporal/spatial 'evolutionary trajectories'. So why 'need' you LIE like that, CS? Control yourself!

Oct 13, 2017
Nobel Prize winner Hannes Alfvén, after which these waves were named, "considered the Big Bang to be a myth devised to explain creation." (Wikipedia). "Alfvén and colleagues proposed the Alfvén–Klein model as an alternative cosmological theory to both the Big Bang and steady state theory cosmologies."

https://en.wikipe...v%C3%A9n

Oct 13, 2017
@RKS, science is not about refuting fairy tales. It does so only as a side effect.

Alfven, by putting it in those terms, subscribed to an agenda for science that is about something other than finding out about reality. By doing so he sabotaged his own beliefs and inadvertently (and ignorantly) lent credibility to fairy tales. This is a shame, but it does not erase his earlier accomplishments.

Oct 14, 2017
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Oct 14, 2017
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Oct 14, 2017
So, what this article is telling us: Astronomers do, in fact, know that plasma exists, do study plasmas, and model plasmas.

Yep, it is telling us they are still using the same old tired MHD models "we know from laboratory experiments to be wrong".
They are even aware of the mythical "Alfven" that the EU cranks are always going on about.

Just mentioning the Alfvenic waves does not mean they are aware of the history of Alfven's claims or his arguments, the scientists still using MHD models flies in the face of this remark. Not to mention the other pseudoscientific claims that the magnetic fields were "stuck" or could "move more freely". BTW, if there is a single reference to an Alfven paper I will gladly eat crow.
Can we finally say that this plugs the holes in the EU "arguments" about how astronomy operates?

Nope, nothing has changed at all. Same old failed MHD models in use, same old pseudoscientific claims....

Oct 14, 2017
Though I still don't understand the claim that craters are caused by lightning strikes? Thundering in a vacuum? I've heard of people hearing voices in their head but thunderclaps from outer space?

This is the type of tripe you get when you "learn" about the science of the EU from dolts and morons such as Cap'n Stoopid and da schnied. The claim is specifically regarding electric discharges in plasmas, lightning being one in which we are familiar with on Earth. It's an analog, a similar breakdown process with the end result of equalizing charges of two or more bodies or regions. It's an expectation in plasmas yet ignored by the plasma ignoramuses.

As far as "lightning" from outer space? It's more real than your ignorance will allow you to accept.
http://ieeexplore...oad=true
http://www.nature...ack=true

Oct 14, 2017
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Oct 14, 2017
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Oct 14, 2017
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Oct 14, 2017
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Oct 14, 2017
"Most people when they paint themselves into a corner will admit their mistake and splash their way out. Mainstream cosmologists turn round and dismantle the corner brick by brick until the building comes down on top of them.

Faced with observations of the motion of galaxies that can't be explained by gravity alone, it would seem reasonable to consider the possibility that electromagnetism might be responsible. After all, since science began physicists have been able to find only four different types of force: gravity, electromagnetism, and the strong and weak nuclear forces, the last two of which act only at very small sub-atomic distances. Unfortunately however, there is less kudos in working with the classical physics of electromagnetism than in an exposition of some unexpected consequence of general relativity, and general relativity only deals with gravity."

- Harry Nielsen, Crisis in Cosmology

Wasn't he the guy who wrote the "Lime in de Coconut" song...?

Oct 14, 2017
"We do not err because truth is difficult to see. It is visible at a glance. We err because the lie is more comfortable."
- Alexander Solzhenitsyn

No. We err because were are conditioned to not accept a "truth" at first glance. It's simply a result of the mechanic of the rationalization/observation process...
Our immediate reaction to something is to compare it to something else.
And Solzhenitsyn was a novelist, not a scientist...

yep
Oct 15, 2017

And Solzhenitsyn was a novelist, not a scientist...

And you are always on hand to defend those liars, that is an art in itself isn't it, but you are correct my immediate reaction is to compare your points to tripe.

Oct 15, 2017

And Solzhenitsyn was a novelist, not a scientist...

And you are always on hand to defend those liars, that is an art in itself isn't it, but you are correct my immediate reaction is to compare your points to tripe.

And my immediate reaction is curiousity about your anger. It only indicates fear.
I only defend common sense causal rationalizations. Point out the lies (with some valid proof) and you'll have my ear...

Oct 15, 2017
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Oct 15, 2017
"We do not err because truth is difficult to see. It is visible at a glance. We err because the lie is more comfortable."

- Alexander Solzhenitsyn

A point of curiousity, Chris...
You included this as a "reference" of sorts. Meaning you are "comfortable" with it...
There's a certain irony to that...:-)


Oct 15, 2017
I always get a good laugh when people try to apply a filter by occupation for wisdom. Wisdom transcends specialization. If you do not get this, then the problem is you.

"Wisdom" is subjective. Ergo, the perception of which can oftentimes change...
If you do not get this, then the problem is you.

Oct 16, 2017
@chris/hannes the pseudoscience eu cult idiot spamming troll

wow... yall just couldn't help yourself, could you?
predicted it!
LMFAO
and ya think ya got wisdom?
lets see about that...
I always get a good laugh when people try to apply a filter by occupation for wisdom
erm... per merriam-webster
1 a accumulated philosophical or scientific learning :knowledge
so, right off the bat you're an epic failure in that you didn't know the primary definition of wisdom actually includes said occupational filter

but ignoring that, as Whyde states: wisdom is subjective
one thing that it does require is: knowledge

here's some knowledge:
the one key element that is left out of every eu poster on the site: actual evidence refuting the science

you make claims, retorts, flood with irrelevant distraction...lots of posts
absolutely no evidence
ever
not one refute of the science
not one prediction, fact or theory

that's fanaticism, not wisdom

yep
Oct 18, 2017
@captainstupid
Wow you just continually miss the point and,
think you have something of worth to share

Erm... Per the whole point being over your head
Philosophical or scientific knowledge

Your epic failure of comprehension
It does not matter Soltzhenitsym was a novelist not a scientist dumb ass that's the point!

As a consensus stooge facts go over your head.
Evidence based on a false priori is not evidence.

You make lots of irrelevant posts without a shred of science.

That's fanaticism, not wisdom.

Oct 18, 2017
I always get a good laugh when people try to apply a filter by occupation for wisdom. Wisdom transcends specialization. If you do not get this, then the problem is you.


And if you don't get that literally EVERYONE here wishes you would stop posting masses of BS to multiple articles the problem is you.

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