Igniting a solar flare in the corona with lower-atmosphere kindling

March 28, 2017
Recent images captured by NJIT's 1.6-meter New Solar Telescope at Big Bear Solar Observatory (BBSO) have revealed the emergence of small-scale magnetic fields in the lower reaches of the corona the researchers say may be linked to the onset of a main flare. Credit: NJIT

Scientists from NJIT's Center for Solar-Terrestrial Research are providing some of the first detailed views of the mechanisms that may trigger solar flares, colossal releases of magnetic energy in the Sun's corona that dispatch energized particles capable of penetrating Earth's atmosphere within an hour and disrupting orbiting satellites and electronic communications on the ground.

Recent images captured by the university's 1.6-meter New Solar Telescope at Big Bear Solar Observatory (BBSO) have revealed the emergence of small-scale magnetic fields in the lower reaches of the corona the researchers say may be linked to the onset of a main flare. The study also includes the first scientific contributions from NJIT's newly commissioned Extended Owens Valley Solar Array (EOVSA).

"These smaller magnetic fields appear as precursors to the flare by reconnecting with each other - breaking apart and forming new connections - in an already stressed magnetic environment. This sets the stage for a larger release," notes Haimin Wang, distinguished professor of physics at NJIT and the leading author of a paper published this week in the magazine Nature Astronomy. The study, funded by the National Science Foundation and NASA, was conducted in collaboration with colleagues in Japan and China.

"Through our measurements, we are able to see the emergence of fine magnetic channel structures prior to the flare, which contain mixed positive and negative magnetic polarities," Wang adds. "We then see a strong twist in the magnetic lines that creates instability in the system and may trigger the eruption."

While solar flares are generally believed to be powered by what is known as free energy - energy stored in the corona that is released by twisting magnetic fields - the authors suggest that the build-up of coronal energy in the upper atmosphere alone may not be sufficient to trigger a flare. In their study of a prolonged flare on June 22, 2015, they observed in unprecedented detail the emergence in the lower atmosphere of what they call precursors, or "pre-flare brightenings," in various wavelengths.

There are well-documented periods in which flares occur more frequently than the norm, but it has been difficult thus far to determine exactly when and where a particular flare might be initiated. The BBSO's recent study of a flare's magnetic evolution, enhanced by simultaneous microwave observations from EOVSA, has been able to pin down the time and location of the magnetic reconnection prior to the flare.

"Our study may help us predict flares with more precision," Wang says.

A co-author of the article, Kanya Kusano of Nagoya University, compared BBSO's observations with his numerical simulation of the triggering process of solar flares.

"I found that the observational result is very well consistent with the simulation," he notes. "This clearly indicates that these mixed-polarity magnetic channel structures are typical of the stressed that triggers ."

Explore further: The Sun's coronal tail wags its photospheric dog

More information: Haimin Wang et al, High-resolution observations of flare precursors in the low solar atmosphere, Nature Astronomy (2017). DOI: 10.1038/s41550-017-0085

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cantdrive85
2.3 / 5 (6) Mar 28, 2017
"This clearly indicates that these mixed-polarity magnetic channel structures..."

That's what one might call an electric current, in techno-speak.
Captain Stumpy
3.8 / 5 (6) Mar 28, 2017
That's what one might call an electric current, in techno-speak.
@nazi-sympathizing idiot eu pseudoscience cult peon

then why don't the plasma physicists writing the study call it that?

maybe because there is a difference and plasma physicists are being very, very specific?

you are just an idiot cult poster attempting to gain credibility for a repeatedly debunked pseudoscience by regurgitating false claims on a science site that refuses to moderate per their own rules

Steelwolf
2.3 / 5 (6) Mar 28, 2017
Ya know Stumped, you Kill yourself every time you say Nazi Sympathizing, because EVERYBODY knows, by just that, that you are ONLY trying to make somebody upset by misrepresenting what they say. You are WAY wrong with nearly every facet of your knowledge about dark matter, plasma and the way you toss around the term Pseudo Science is Just like the people that naysayed Galileo and Copernicus, Tombaugh and Even Einstein, until they proved everyone else wrong with undeniable proofs.

Such new proofs have already come out that kill Dark Matter, and the major dark energy is Magnetics.

You should know by now that the first person in an argument to bring up the nazis is the AUTOMATIC loser?
691Boat
5 / 5 (3) Mar 29, 2017
"This clearly indicates that these mixed-polarity magnetic channel structures..."

That's what one might call an electric current, in techno-speak.

From the article:
"These smaller magnetic fields appear as precursors to the flare by reconnecting with each other - breaking apart and forming new connections - in an already stressed magnetic environment. This sets the stage for a larger energy release"
oh no! that dang magnetic reconnection happened again, CantDrive!
But, if it is an electric current like you say, we should be able to see the magnetic fields around these currents change as the electric currents increase or decrease, right?
Captain Stumpy
3 / 5 (2) Mar 29, 2017
you Kill yourself every time you say Nazi Sympathizing, because EVERYBODY knows, by just that, that you are ONLY trying to make somebody upset by misrepresenting what they say
@steel
it is a factual label based upon cd's historical posts and his refusal to accept factual evidence of the holocaust as well as his supporting of nazism as cd or his various socks ( https://phys.org/...her.html )
You are WAY wrong with nearly every facet of your knowledge about dark matter
this coming from someone who can't produce any evidence at all whatsoever refuting the studies, links and references that i've provided in the past?
LMFAO
the first person ...to bring up the nazis is the AUTOMATIC loser?
just like the first person to support a known pseudoscience like the eu is an automatic loser

.

also - proving conspiracist ideation warns others off the nutters like you and cd
http://phys.org/n...ris.html
cantdrive85
1 / 5 (2) Mar 29, 2017
But, if it is an electric current like you say, we should be able to see the magnetic fields around these currents change as the electric currents increase or decrease, right?

The tight spiraling filaments are the electric currents, the plasma trapped in the magnetic fields they create trace out the phenomena.
""In order to understand the phenomena in a certain plasma region, it is necessary to map not only the magnetic but also the electric field and the electric currents." Hannes Alfven
cantdrive85
1 / 5 (2) Mar 30, 2017
But, if it is an electric current like you say, we should be able to see the magnetic fields around these currents change as the electric currents increase or decrease, right?

The most obvious indication the current density of the electric currents increases is they achieve arc mode discharge.

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