Sun's core rotates four times faster than its surface

August 1, 2017 by Stuart Wolpert, University of California, Los Angeles
The sun is emitting plumes of hydrogen plasma. The white areas are where the sun’s magnetic field is especially strong. Credit: SoHO, a joint project of the European Space Agency and NASA

The sun's core rotates nearly four times faster than the sun's surface, according to new findings by an international team of astronomers. Scientists had assumed the core was rotating like a merry-go-round at about the same speed as the surfa

"The most likely explanation is that this core rotation is left over from the period when the sun formed, some 4.6 billion years ago," said Roger Ulrich, a UCLA professor emeritus of astronomy, who has studied the sun's interior for more than 40 years and co-author of the study that was published today in the journal Astronomy and Astrophysics. "It's a surprise, and exciting to think we might have uncovered a relic of what the sun was like when it first formed."

The rotation of the solar core may give a clue to how the sun formed. After the sun formed, the likely slowed the rotation of the outer part of the sun, he said. The rotation might also impact sunspots, which also rotate, Ulrich said. Sunspots can be enormous; a single sunspot can even be larger than the Earth.

The researchers studied acoustic waves in the sun's atmosphere, some of which penetrate to the sun's core, where they interact with that have a sloshing motion similar to how water would move in a half-filled tanker truck driving on a curvy mountain road. From those observations, they detected the sloshing motions of the solar core. By carefully measuring the acoustic waves, the researchers precisely determined the time it takes an acoustic wave to travel from the surface to the center of the sun and back again. That travel time turns out to be influenced a slight amount by the sloshing motion of the gravity waves, Ulrich said.

The sun, whose hot, dense core produces nuclear fusion and rotates nearly four times faster than its surface. Credit: University of California, Los Angeles

The researchers identified the sloshing motion and made the calculations using 16 years of observations from an instrument called GOLF (Global Oscillations at Low Frequency) on a spacecraft called SoHO (the Solar and Heliospheric Observatory)—a joint project of the European Space Agency and NASA. The method was developed by the researchers, led by astronomer Eric Fossat of the Observatoire de la Côte d'Azur in Nice, France. Patrick Boumier with France's Institut d'Astrophysique Spatiale is GOLF's principal investigator and a co-author of the study.

The idea that the solar core could be rotating more rapidly than the surface has been considered for more than 20 years, but has never before been measured.

The core of the sun differs from its surface in another way as well. The core has a temperature of approximately 29 million degrees Fahrenheit, which is 15.7 million Kelvin. The sun's surface is "only" about 10,000 degrees Fahrenheit, or 5,800 Kelvin.

A type of wave detected on the Sun by ESA and NASA's Solar and Heliospheric Observatory, or SOHO, reveals that the solar core is rotating about four times faster than the surface. Credit: ESA/NASA

Ulrich worked with the GOLF science team, analyzing and interpreting the data for 15 years. Ulrich received funding from NASA for his research. The GOLF instrument was funded primarily by the European Space Agency.

SoHO was launched on Dec. 2, 1995 to study the sun from its to the outer corona and the solar wind; the spacecraft continues to operate.

Explore further: Has SOHO ended a 30-year quest for solar ripples?

More information: E. Fossat et al. Asymptotic g modes: Evidence for a rapid rotation of the solar core, Astronomy & Astrophysics (2017). DOI: 10.1051/0004-6361/201730460 , www.aanda.org/articles/aa/abs/ … 0-17/aa30460-17.html

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Old_C_Code
4.3 / 5 (3) Aug 01, 2017
"The core has a temperature of approximately 29 million degrees Fahrenheit, which is 15.7 million Kelvin. The sun's surface is "only" about 10,000 degrees Fahrenheit, or 5,800 Kelvin."

And the Sun's corona above the 'cool' surface is 2 million kelvin. Go figure.
wduckss
1 / 5 (6) Aug 01, 2017
"The solar wind likely slowed the rotation" from article
The scientist must know that stars generate solar wind and that the minor value of solar wind opposite the friction material within the Sun.

"The sun, whose hot, dense core produces nuclear fusion" from article
Sunspots are proof that within the star there is dislocation of matter between the layers. Observing nuclear fusion without the existence of radioactive radiation is not a science.

For a discussion faster rotation center of body , see:
http://www.svemir...#cykloni (2013.y.)
Old_C_Code
2.7 / 5 (7) Aug 01, 2017
"Observing nuclear fusion without the existence of radioactive radiation is not a science." -- wduckss

There is a lot of fusion at the Sun, it's just TWO THIRDS LESS (emitted neutrinos) than to be expected with that size H-He conversion.
IMP-9
4.7 / 5 (15) Aug 01, 2017
There is a lot of fusion at the Sun, it's just TWO THIRDS LESS (emitted neutrinos) than to be expected with that size H-He conversion.


No, the number of emitted neutrinos matches expectations, it's the number of electron neutrinos that was lower than expected before neutrino oscillations were established and experimentally confirmed.
billpress11
1 / 5 (1) Aug 01, 2017
Quote from article: "The most likely explanation is that this core rotation is left over from the period when the sun formed, some 4.6 billion years ago,"

How would this explain the difference? Could a much more possibly dense core explain the difference? If so how would we explain the solid core? Oliver, where are you?
Gigel
5 / 5 (1) Aug 01, 2017
How would this explain the difference? Could a much more possibly dense core explain the difference? If so how would we explain the solid core? Oliver, where are you?

Well, the Sun's core is far denser than its outer layers. The core is compressed to enormous pressures.
cantdrive85
2.2 / 5 (10) Aug 01, 2017
How would this explain the difference? Could a much more possibly dense core explain the difference? If so how would we explain the solid core? Oliver, where are you?

Well, the Sun's core is far denser than its outer layers. The core is compressed to enormous pressures.

Wild conjecture stated as a fact due to belief in unfounded maths.
Captain Stumpy
5 / 5 (3) Aug 02, 2017
Understood better than you ever will
@bs
then by all means, please present your evidence that the MS models are false

and before you mention the whole "current solar model cannot explain" argument again, remember this: just because they don't know it now doesn't mean that
1- it will never be known (Newton)
2- it can't be known (again, Newton)
3- that the current model is wrong (again, Newton)

i used Newton for it's obvious relevance: not only was his model expansion bringing knowledge to what was not known, but he gave up and said it couldn't be known and it is still used because, though it's not 100% accurate, it's still a functional model that works and isn't falsified (excepting relativistic speed)

it just didn't explain everything, yet it lead to that which explained far more - which is very relevant to the above
Captain Stumpy
5 / 5 (3) Aug 02, 2017
@bs cont'd
now, i downrated your comment because of this
Stable particle physics or IOW plasma physics are applicable...not mathematical fairytales
you make the claim, but you don't demonstrate it's fairy tale status

the mathematics of solar physics are based upon known plasma physics and stable particle physics with application of known data that is measured, modeled and then observed

so if you want to poo-poo helioseismology and it's physics, you should be very specific, otherwise you're no better than the eu nutters

as for this
I have made a simple observation that you don't like
you've made what you feel is a valid observation without having knowledge of the requisite data, maths or evidence

otherwise you would have presented the falsification of the study and physics

the rest is your venting at the org that refuses to allow pseudoscience or your beliefs over the current evidence

see Newton above
Dingbone
Aug 03, 2017
This comment has been removed by a moderator.
Dingbone
Aug 03, 2017
This comment has been removed by a moderator.
nikola_milovic_378
Aug 04, 2017
This comment has been removed by a moderator.
nikola_milovic_378
Aug 04, 2017
This comment has been removed by a moderator.
Dingbone
Aug 04, 2017
This comment has been removed by a moderator.
nikola_milovic_378
Aug 04, 2017
This comment has been removed by a moderator.
antialias_physorg
4.3 / 5 (6) Aug 04, 2017
What possible purpose can you have to come here and shout off about how wrong everybody (i.e. all the thousands of scientists actually employed to do the job over many decades) has been

Where else would he do it? There's no way he'd do it where actual physicists are around. Shouting about how all is oh-so-terrible is cool as long as one can hide in safe anonymity. But actually going out and publishing something (or even presenting it at a conference)? No way. That'd take actual work

...which isn't the point. His point is merely to make it look like he's worth something to anyone. And on the internet he can just go the full hog and make believe that he's worth something to *everyone* by claiming to be super-genius.

Yeah...that it ain't working hasn't really sunk in. But then again - if someone is stupid enough to think this kind of scam would work, they're never gonna get wise that all they're doing is shouting "I'm an idiot" at the top of their lungs to the world.
Dingbone
Aug 04, 2017
This comment has been removed by a moderator.
Ojorf
4.3 / 5 (4) Aug 04, 2017
To be honest, you cannot expect or publish at the conference some critique of scientific community - such a thing wouldn't even pass the internal filter of editors, not to say peer-review.


Well unless you have a theory/idea that you can prove with rigorous math, backed up by real data that does not conflict with other thoroughly and exhaustively well tested theories.
Captain Stumpy
4 / 5 (4) Aug 04, 2017
To be honest, you cannot expect or publish at the conference some critique of scientific community - such a thing wouldn't even pass the internal filter of editors, not to say peer-review.
@dingbat zeph
1- as Ojorf points out, you're full of sh*t because you don't know squat about the scientific community except what you dreamed up in your delusional D-K brain

2- to prove you're a whinging idiot with no evidence and Ojorf is correct, go here: https://www.ncbi....=5.55556

The reason usually is, the commenters are stupid so they don't even realize, that their remarks have no relation to subject - or they're using it intentionally as an evasion for pushing their own agenda (also irrelevant to subject in a given moment).
holy sh*t! pot-kettle!

were you attempting to go for irony or just describing your own tactics for confirmation?
LOL

pseudoscience falsified aether =/= science!
Dingbone
Aug 04, 2017
This comment has been removed by a moderator.
Captain Stumpy
4 / 5 (4) Aug 04, 2017
@dingbat zeph cont'd
You cannot beat the problems of scientific community just by acting in the same way. The verbosity of well minded critics of scientific community brings no competition for well minded verbosity of scientific community
and again, your epic failure to comprehend the scientific method is where you fall flat on your face in ignorance (argument from ignorance means you'll never be correct)

it isn't about verbosity, nor is it about verbose critiquing or reply

*!it's all about the evidence!*

this is why you can't break into the community: you don't have evidence that isn't already falsified by better (copious amounts of) evidence

that you don't understand the evidence means nothing to the community, nor does railing against scientists because you don't understand

there is only one solution: https://en.wikipe...c_method

failure to use it = pseudoscience
not accuracy
not reality

your beliefs are religion, not science
Captain Stumpy
4 / 5 (4) Aug 04, 2017
This is all BS which has nothing to do with article subject and which I've no reason to comment right here.
@dingbat zeph
LOL
so you got caught lying and OT ranting about scientist, and now you want to point the finger at others for outing you?

if it's not relevant then why did you comment about it right here?

I mean, this is all in direct reply to your own false claims about the scientific community

it is also backed by evidence of a level that you, yourself, have never presented in refute of the science (and scientists) you denigrate

it may well not be relevant to the article, but it is directly relevant to your own pseudoscience BS lying posts

and downrating it only shows i am correct about you! LMFAO
it doesn't make you more correct (or correct at all)
LMFAO
antialias_physorg
4.3 / 5 (6) Aug 04, 2017
To be honest, you cannot expect or publish at the conference some critique of scientific community - such a thing wouldn't even pass the internal filter of editors, not to say peer-review

Total bull. I've seen it happen at the last conference I was at. In a session on brain connectivity studies the last talk was from someone who critiqued the use of brain atlases as the various atlases can lead to studies that show significance whereas the use of a different atlas might have lead a study to not be able to show significance.

Guess what: That talk got the most applause.

You're just a loser who lives in a fantasy you're concocting inside your tiny brain. The real world works nothing like you imagine. Nothing.

If you actually have something to publish the do so. Don't hide in fear from your own failure. People out there are doing good work. You're just a loser-troll. Guess who is worth something? You certainly aren't. Your life is/was a waste.
Captain Stumpy
4 / 5 (4) Aug 04, 2017
Three times Stump
@BS
1- argument from ignorance

2- since you obviously know far more than the myriad world plasma physicists in labs, feel free to write up your observations and publish in a peer reviewed journal with an impact in astrophysics
want us to accept that you have a definitive understanding of the parts you can't
sigh
important point- please, for all laymen out there: why should anyone accept "your (or any) argument or suppositions with no evidence etc" over the "still working and adapting to new data current MS theory" that is backed by validated evidence?

the only way to make incremental steps based on fact is to utilise the scientific method

this means: https://en.wikipe...c_method

asking questions is fine

stating something is "mathematical fairytales" when you have neither the education nor the evidence means you're talking religion, not science

it's also delusional and D-K
RealityCheck
2.3 / 5 (3) Aug 04, 2017
TIMELY REMINDER TO WHOM IT MAY CONCERN

This is a news site with comments/discussion section open to all interested in commenting/discussing fairly, with the understanding that the logical/scientific validity or otherwise of any OPINIONS and/or CLAIMS in posts made here are the responsibility of the READER to check out further FOR THEMSELVES via further research/cogitation having regard to ALL available facts and possibilities of revision and correction which THE SCIENTIFIC METHOD dictates MUST be done/applied on a case-by-case basis and as the evolving observational/re-examinational situation demands of ANYONE purporting to be 'doing science discourse', whatever the venue or milieu, here on PO or elsewhere....and WITHOUT FEAR, FAVOR, RANCOR or BIAS of ANY KIND.

NOTE: If one is merely looking to get the current textbook orthodoxy, they should consult same in forums catering for same; as distinct from forums such as these which discuss new/developing science/issues. Cheers.

f_darwin
not rated yet Aug 05, 2017
The signal is from one of the layers, not what they refer to as core. MG1
RealityCheck
1 / 5 (2) Aug 05, 2017
@Forum.
Dingbone said: To be honest, you cannot expect or publish at the conference some critique of scientific community - such a thing wouldn't even pass the internal filter of editors, not to say peer-review
antialias said: Total bull.
Taking off any 'rose-colored glasses', we see the reality: Recent professional science discussions/articles/studies etc, re serious flaws in both peer review/publishing and 'organized' venues/forums/grants etc situations, should have burst everyone's 'innocence' bubble by now. The 'reception/acceptance' of any particular industry/field-criticizing paper/talk, depends on who organized/reviewed/approved the talk/paper, and whether it is controversial to the point of threatening the reputations/livelihoods of those who have been highly invested in the 'status quo' or not; and how many of those make up the 'target audience' in any one 'event'. That is why DECADES can pass before flawed 'science' self-corrects. Buyer Beware! :)
TimLong2001
not rated yet Aug 07, 2017
I assumed that everyone was aware of the variation of solar internal rotation rates as the dynamo generating the sunspot cycle -- similar to the Earth's magnetic field reversal cycle.

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