New research brings light to star mystery

Feb 04, 2013
Magnetic loop structures in the corona of the Sun. The loops highlight the Sun’s magnetic field and are visible because they support the dense, million degree gas typical of the corona. The image is courtesy of the Science Team for NASA’s Solar Dynamic Observatory.

(Phys.org)—Scientists at Northumbria University have begun to unlock the mystery of why the outer edge of the Sun is much hotter than its surface for the first time.

A team led by Northumbria's Dr Richard Morton, and including researchers from the University of Sheffield and Queen's University Belfast, have used cutting-edge solar-imaging technology to observe the Sun's chromosphere – a region of the Sun's atmosphere sandwiched between its surface (photosphere) and outer layer (corona) – to an unprecedented level of detail.

For years astronomers have looked for the elusive mechanism that causes some to have a corona that is almost 200 times hotter than their , despite being further away from the at the star's core. It is believed that the cause of the increased temperature is due to magnetohydrodynamic (MHD) waves that distribute the energy generated below the star's surface to the outer layers of the Sun's atmosphere

Now, for the first time, the team has examined the MHD waves using a UK-designed dedicated solar-imaging telescope known as Rapid Oscillations in the , or ROSA, to observe the chromosphere with a high degree of clarity. The powerful tool enabled some of the highest resolution images of the chromosphere to be obtained, allowing the scientists to study the speed and power of the waves and then estimate the amount of energy that they transport.

Their calculations confirm that the MHD waves could be responsible for transporting energy from below the , out through the chromosphere, into the corona and leading to heating of the outer layers in excess of a million degrees.

Dr Morton said: "The Sun is our closest star and provides a unique opportunity to study the properties of stars in detail. Stars generate heat through in their core and the temperature decreases towards the star's surface. However, a significant number of stars have higher temperatures at the outer edges of their atmospheres than they do on their surface.

"Our observations have permitted us to estimate the amount of energy transported by the magnetic waves, and these estimates reveal that the ' energy meets the energy requirement for the unexplained temperature increase in the corona."

Northumbria University has launched a new Physics with Astrophysics degree, which will begin in September 2013. The course will teach aspects of modern astrophysics, including modules on the Sun and its properties.

The team's findings have been published in Nature Communications, an online journal.

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User comments : 10

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gwrede
4.2 / 5 (5) Feb 04, 2013
Yes, but Electrical Universe. No, but Dense Aether Waves. Or is it God who shows us his power through the Magnetics on the Sun's surface? But science, anyone? Naww, science is so Old School. And much of it uses, gasp, math!
ValeriaT
1 / 5 (5) Feb 04, 2013
The mystery of hot solar corona gets "solved" regularly each year. Many coronal heating theories have been proposed, but three theories have remained as the most likely candidates, Alphen waves, magnetic reconnection and nanoflares. Through most of the past 50 years, neither theory has been able to account for the extreme coronal temperatures, though. IMO it's the result of heating solar plasma with neutrinos escaping from Sun.
yep
1.5 / 5 (8) Feb 05, 2013
Those scientists might want to read " The Photosphere: Is It the Top or bottom of the Phenomenon we call the Sun" Ralph E Juergens Kronos Vol. IV No. 4 summer 1979
"The photosphere as a whole seems to add up to yet another strong indication that the Sun draws its energy not from within itself but from its cosmic environment, and that the delivery mechanism is an electric discharge embracing the entire solar system".
yep
1.5 / 5 (8) Feb 05, 2013
Math is binding us to Eddington's standard model of the sun proposed in 1920 like math bound us to the Earth centered Ptolemaic model of the heavens. Hopefully this ends before we hit a hundred years of misguided thinking instead of the thousand years that beautiful math stuck us with before. Why make it so difficult? Eliminate the priori take a new look. The electrical model works.
Torbjorn_Larsson_OM
5 / 5 (6) Feb 05, 2013
The article is a bit misleading. New observations are good, but plenty of mechanisms have already been proposed, several of which are able to predict the heating. The problem is not prediction, but to test with these observations.

qwrede, of course EU/aether/creationism, see the thread. Never mind that the article states clearly that EM is the energy transport mechanism and fusion is the generating mechanism.
Torbjorn_Larsson_OM
4.2 / 5 (6) Feb 05, 2013
@yep: Provide peer review references on the failure of the standard solar models ("misguided") and on the success of "the electrical model".

I predict that you can't, since everyone knows astronomers use the former is used and not the latter.

And since you can't, please take your anti-science to your own crackpot sites. I come here for the science, not your nonsense.
rubberman
2.3 / 5 (6) Feb 05, 2013
"The electrical model works." - Yep

No, it doesn't. Although it has it's positives (no pun intended). At the end of the day it fails because of the quote in your first post regarding external power. Tor asked you for a peer reviewed reference which he knows you won't find because there is no mechanism for the sun to draw the power from interstellar space to power the magnetic fields at the levels present on/in/around the sun.

Simply put, we would detect this if it were the case. At any given time there are many "eyes" trained on the sun and what it is doing. Check out the article on "flux ropes".
yep
1.9 / 5 (9) Feb 06, 2013
The flux ropes are field aligned birkeland currents, same thing different name.
" The failures of standard solar theory", lately slow convection speed is the biggie since the mainstream gas model is dependent on those particles mixing together at "jet like speeds".
Nasa's Ibex has mapped the boundary between the heliosphere and interstellar space. The principle investigator David McComas says" Our previous ideas about the outer heliosphere are going to have to be revised." " I'm blown away completely." Space physicist Neil Murphy added " it's amazing it's opened up a new kind of astronomy" So the sun's helio-sheath is dominated not by the sun but the galaxy's magnetic field. The ribbon they found is evidence of the Z pinch or Bennett pinch. Stars are positive anodes in galactic discharge.
I'm not anti-science I just want you old dinosaurs to wake up and realize your beautiful birds now!
rubberman
1 / 5 (1) Feb 06, 2013
Yep - Do you realize the energy density required to actually create a Z-pinch. That ribbon doesn't even occur in the visual spectrum. As far as the Heliosphere, the most important info to what is happening out there has come from voyager which is currently traversing a region they have named the "magnetic highway", where it experienced an order of magnitude increase in the velocity of the particles which constitute the helio sheath. Magnetic fields couple or repel, the structure of the fields has indeed been mapped by IBEX, they are identical in the vicinity of earth and at the inner boundary of the heliosheath, the only difference is the size of the structures and intensity of the field boundaries.
Stars, like all bodies have dual polarity (flips every 11 years or so). Magnetic fields can induce a mild shift towards positive or negative, but it is impossible for anything to only exist as either or.
How does the EU explain gravity, the "magnetic universe" has no trouble.
Sepp
1 / 5 (2) Feb 16, 2013
Magnetics as a result of rotation - leads to extreme heat at a preferred distance interval. Sun's surface temp is what ... just under 6000 K? My question is: how does the standard model explain the putative intense internal heat from fusion to be almost completely lost at sun's surface, yet be re-created in photosphere and corona? It seems an illogical set of facts that isn't addressed anywhere I can see.