MESSENGER and STEREO measurements open new window into high-energy processes on the Sun

Jul 09, 2014 by Karen C. Fox
A solar flare erupted on the far side of the sun on June 4, 2011, and sent solar neutrons out into space. Solar neutrons don't make it to all the way to Earth, but NASA's MESSENGER, orbiting Mercury, found strong evidence for the neutrons, offering a new technique to study these giant explosions. Credit: NASA/STEREO/Helioviewer

Understanding the sun from afar isn't easy. How do you figure out what powers solar flares – the intense bursts of radiation coming from the release of magnetic energy associated with sunspots – when you must rely on observing only the light and particles that make their way to near-Earth's orbit?

One answer: you get closer. NASA's MESSENGER spacecraft—which orbits Mercury, and so is as close as 28 million miles from the sun versus Earth's 93 million miles—is near enough to the sun to detect solar that are created in . The average lifetime for one of these neutrons is only 15 minutes. How far they travel into space depends on their speed, and slower neutrons don't travel far enough to be seen by particle detectors in orbit around Earth. Results showing that MESSENGER has likely observed solar neutrons appeared in the Journal of Geophysical Research: Space Physics on July 9, 2014.

"To understand all the processes on the sun we look at as many different particles coming from the sun as we can – photons, electrons, protons, neutrons, gamma rays –to gather different kinds of information," said David Lawrence, first author of the paper at The Johns Hopkins Applied Physics Lab in Laurel, Maryland. "Closer to Earth we can observe charged particles from the sun, but analyzing them can be a challenge as their journey is affected by magnetic fields."

Such charged particles twirl and gyrate around the created by the vast magnetic systems that surround the sun and Earth. Neutrons, however, as they are not electrically charged, travel in straight lines from the flaring region. They can carry information about flare processes unperturbed by the environment through which they move. This information can be used by scientists to decipher one aspect of the complicated acceleration processes that are responsible for the creation of highly energetic and fast solar particles.

Lawrence and his team looked at MESSENGER data from June 4 and 5, 2011, corresponding to solar flares that were accompanied by fast-moving, energetic charged particles. The flare occurred on the far side of the so Earth-based views of the flare region could not be obtained. However, a solar telescope on NASA's Solar Terrestrial Relations Observatory, or STEREO, spacecraft did have a clear view of the far-side flare region. STEREO provided useful observations of the flare. This combined use of NASA mission data makes each individual mission more effective in addressing unsolved science questions.

The MESSENGER data showed an increase in the number of – not electrically charged—neutrons at Mercury's orbit hours before the large number of reached the spacecraft. This indicated that the neutrons were most likely produced by accelerated flare particles striking the lower solar atmosphere, releasing neutrons as a result of high-energy collisions. So, together, the MESSENGER and STEREO data can provide new information about how particles are accelerated in solar flares.

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cantdrive85
2.3 / 5 (6) Jul 09, 2014
The neutrons are created by the z-pinched plasma in the exploding filaments of field aligned currents flowing through the sun. The z-pinch is a common occurrence even here on Earth, here is an excellent explanation of the z-pinch and it's effects.

https://str.llnl....013/tang

Note his guy explicitly says;
[Schmidt, who leads the simulation effort, explains, "We had to use the more computationally intensive particle approach instead of a fluid approach because the plasma distribution functions are not Maxwellian. The ions form beams when they accelerate, and high electric fields are created partially through kinetic electron instabilities that are not modeled in a fluid code. Until recently, though, we just didn't have the computing power or the tools to model a plasma particle by particle."]

Sounds like what Alfven said some 40 years ago. Nice to see someone is listening.


Captain Stumpy
3 / 5 (4) Jul 10, 2014
Sounds like what Alfven said some 40 years ago
@cant read
no it doesn't
specify what you are saying, because what I read
Until recently, though, we just didn't have the computing power or the tools to model a plasma particle by particle
is NOT what you've claimed fallaciously in the past regarding the modelling of plasma's in astrophysics.

your article actually reinforces what I have been telling you all along, especially about plasma physics.
You seem to think that only you EU acolytes are exposed to plasma physics, or is that EE's? It doesn't matter, though, because the SAME information THEY learn and deal with is taught to astrophysicists. but I digress- this guy essentially said that computationally, they had the ability and resources to look closer into the issue.

there is nothing in the article that suggests that only EU acolytes or EE's know anything about plasma physics, per your previous ad nauseum claims
cantdrive85
2.6 / 5 (5) Jul 10, 2014
You too can read his Nobel lecture, skip to the 3rd section if there are too many words;

http://www.nobelp...ture.pdf

"The plasma exhibited striations (beams) and double layers (electric fields), the electron distributions was non-Maxwellian, there were all sorts of oscillations and instabilities"

Then there is this paper;

http://www.diva-p...XT01.pdf

"As neither a double layer or circuit can be derived from magnetofluid models of a plasma, such models are useless for treating energy transfer by means of DL's."

It doesn't matter, though, because the SAME information THEY learn and deal with is taught to astrophysicists.


That's what you believe, however as usual the facts contradict this claim. If you choose to read the second linked paper you can see he discusses the omission of DL's and other important plasma phenomena in astrophysical texts.

Being that nearly every astrophysical model still uses fluid MHD models it would seem Alfven's claims are still valid to this day. And to claim that they didn't have the "computational capabilities" is a strawman, Alfven was capable of creating his models decades ago without such ability.
Captain Stumpy
3.7 / 5 (3) Jul 12, 2014
That's what you believe, however as usual the facts contradict this claim
@cd
what "facts"?
so far, every time you've made this claim its been proven to you that you were wrong!
If you choose to read the second linked paper you can see he discusses the omission of DL's and other important plasma phenomena in astrophysical texts
in 1986
what is todays date?
and I have proven to you that this is wrong, even including comments from the author of one study that you claim used only MHD and didn't know anything about plasma: remember Julie Hlavacek-Larrondo? you called her a him? AND she gave you a link that supported her comment
Being that nearly every astrophysical model still uses fluid MHD models it would seem Alfven's claims are still valid to this day
and at least 4 astrophysicists (including J.H) have told you this is untrue and that MHD also includes plasma physics, and that even if you see MHD models used, PP was also included.
Captain Stumpy
3.7 / 5 (3) Jul 12, 2014
And to claim that they didn't have the "computational capabilities" is a strawman
@cd
i didnt make the claim, I quoted the article. THEY made the claim
argue it with them
Being that nearly every astrophysical model still uses fluid MHD models it would seem Alfven's claims are still valid to this day
and since this has been proven, with courses and links to plasma physics pages, time and again, that you are WRONG, the ONLY WAY that you will ever learn is to take the courses yourself
http://ocw.mit.edu/index.htm
start at that link. when you get the education, or when you can find a college that teaches ONLY MHD and NO Plasma Physics in their astrophysics course, then please link it here as empirical proof of statement

until then, it is simply an oft repeated lie. YOU'VE had proof posted as nauseum showing that your above statement is incorrect... check out MIT
but you've offered ZERO proof that it IS correct, only decades old sound bytes.
where is your PROOF
enter socks!
cantdrive85
2 / 5 (4) Jul 12, 2014
what "facts"?
so far, every time you've made this claim its been proven to you that you were wrong!

The fact listed in the paper you did not read again, willful ignorance is no argument.

I have provided a peer reviewed paper with references. You on the other hand respond with; nuh uh, so and so said this or that...

when you can find a college that teaches ONLY MHD and NO Plasma Physics in their astrophysics course

Reading your post further indicates you still don't even understand the argument.

i didnt make the claim, I quoted the article. THEY made the claim
argue it with them

Peratt has been using supercomputers since the early 80's, achieving similar results as the LLNL physicist quoted above.

That being said, where in the above article do they discuss electric currents, electric fields, or instabilities he mentions that are found in plasmas?
Captain Stumpy
3.4 / 5 (5) Jul 12, 2014
I have provided a peer reviewed paper with references
@cd
yup. the 1986 and 1970 speech.
saw that.
and this is proof that nowadays modern astrophysicists don't know anything about plasma physics, then? really? did you check out my link?
Reading your post further indicates you still don't even understand the argument
WHICH ONE? the one where yo are claiming that the world stopped in 1986 and no one (but the EU) ever learned anything new? or the one claiming that you are correct?
YOU CONTINUALLY ARGUE THAT NO MODERN ASTROPHYSICISTS COMPREHENDS PLASMA PHYSICS AND THUS CANNOT COMPREHEND MODERN ASTROPHYSICS.

YOU"VE OFFERED ZERO PROOF TO ESTABLISH THIS AS FACT.
THIS IS THE ARGUMENT THAT I AM ARGUING. ANYTHING ELSE IS YOUR ATTEMPT AT DIVERSION
Peratt has been using supercomputers since the early 80's
Guess you really can't read! i told you, argue with the authors. I was only passing on their claims.

PROVIDE PROOF that modern schools don't teach plasma physics, please
cantdrive85
1 / 5 (3) Jul 13, 2014
PROVIDE PROOF that modern schools don't teach plasma physics, please

That was never the claim, and after all this time you are just too dumb to understand. Alfven described the two schools of thought when it comes to modeling plasmas, the LLNL physicist quoted above basically said the exact same thing Alfven said decades ago. If astrophysicists used the same modern plasma theory that Alfven helped develop you'd be reading a lot more about field aligned electric currents, DL's, CIV, electric fields, Bennett pinch effects, Marklund convection, and other plasma processes which they seem to ignore for the most part, this is a fact with no conjecture. These phenomena are ubiquitous in all plasmas in the lab and that have been measured via in situ research. I will agree there are some making strides in this direction, but for a large part it is more like turning a sinking Titanic in a bath tub than a kayak in a calm lake.
Captain Stumpy
5 / 5 (2) Jul 13, 2014
That was never the claim
@CD
perhaps that was not your INTENT above, but given your propensity for posting that very claim (that astro's don't study/know plasma physics) then It is natural to assume that I would take that into consideration and refute it with said posts above, to which you STILL have never been able to refute or provide empirical data supporting your assertions
you are just too dumb to understand
personal conjecture without evidence; attempt at redirection
If astrophysicists used the same modern plasma theory that Alfven helped develop blah blah blah this is a fact with no conjecture
No, it is NOT, and if you were to take (or HAD taken) ANY school curriculum for astrophysics, You would already know that it is NOT true, so given that you cannot provide PROOF of this claim (astro's don't learn alfie's plasma phys.) then, AGAIN, it is conjecture without evidence and only conclusively supports my argument
Captain Stumpy
5 / 5 (2) Jul 13, 2014
These phenomena are ubiquitous in all plasmas in the lab and that have been measured via in situ research
@CD
PLASMA physics labs like http://www.pppl.gov/ have sections like Science Education where people like Zwicker educate about plasma physics.
These are the things that end up in astrophysics books when learning about cosmology.
Your claims
If astrophysicists used the same modern plasma theory that Alfven helped develop...which they seem to ignore for the most part, this is a fact with no conjecture
are only, and I MEAN ONLY supported by your insistence and your pseudoscience web-site.

IF you had a leg to stand on... AND you can prove that modern astrophysicists DON'T learn about plasma physics, you would have posted a zillion links to school curriculum proving your point, much like you post links to your known pseudoscience site hoping someone will actually believe it.

EXTRAORDINARY CLAIMS REQUIRE EXTRAORDINARY PROOF
you've made the claim, BUT YOU CANNOT PROVE IT
Captain Stumpy
5 / 5 (2) Jul 13, 2014
I will agree there are some making strides in this direction, but for a large part it is more like turning a sinking Titanic in a bath tub than a kayak in a calm lake
@cd
this is sad, really. You continually infer that modern astrophysicists are pretty much still stuck in the 1970-80's because your idol said so, and because physics PROVED your EU pseudoscience.
HERE IS EMPIRICAL PROOF THAT MODERN ASTROPHYSICISTS LEARN PLASMA PHYSICS
http://www.pppl.g...ophysics

YOU HAVE YET TO PROVIDE EVEN ONE SCHOOL THAT DOES NOT TEACH MODERN PLASMA PHYSICS TO ITS ASTROPHYSICS PROGRAM

with ONE link, I have COMPLETELY undermined your argument and proven that you are completely wrong.
I also gave you the MIT link
perhaps you should TAKE SOME COURSES so that you know what you are talking about?
but I know that IF you DID... you would no longer support EU

feel free to show empirical proof of claims from legitimate reputable science sites, like I did
cantdrive85
1 / 5 (3) Jul 13, 2014
You continually infer that modern astrophysicists are pretty much still stuck in the 1970-80's because your idol said so, and because physics PROVED your EU pseudoscience.

They infer it themselves by the papers they write and dated theories they continue to uphold. And actually, they infer they're working with theoretical models developed starting in the 20's with Chapman and rudimentary gravity driven MHD plasma modeling from the 50's. The reason there is one surprise after another along with mystery after mystery is due to those dated gas light era theories. Listen to the LLNL plasma physicist, he's trying to send a message to all those working with plasmas.
Captain Stumpy
5 / 5 (3) Jul 13, 2014
@cd
They infer it
based upon empirical data and experiments
the papers they write
are based upon the laws of physics and empirical data
theories they continue to uphold
also based upon empirical data and laws of physics
rudimentary gravity driven MHD plasma modeling from the 50's
which I've already shown you has been updated over the last 40 years, which you ignored. see above links/read modern MHD in astrophysics classes IF YOU CAN
Listen to the LLNL plasma physicist, he's trying to send a message
and the modern era is still trying to get a hold of YOU

you STILL have not proven that modern astro's don't learn plasma physics or that MHD hasn't changed since your 50's
personal conjecture is NOT the same as EMPIRICAL EVIDENCE

you've been given EMPIRICAL EVIDENCE that you are wrong
YOU IGNORE EMPIRICAL EVIDENCE because it does not jibe with your faith in EU
you have ZERO evidence in return