From Columbia University
Astronomers find clues to decades-long coronal heating mystery
Drs. Michael Hahn and Daniel Wolf Savin, research scientists at Columbia University’s Astrophysics Laboratory in New York, NY, found evidence that magnetic waves in a polar coronal hole contain enough energy to heat the corona and moreover that they also deposit most of their energy at sufficiently low heights for the heat to spread throughout the corona. The observations help to answer a 70-year-old solar physics conundrum about the unexplained extreme temperature of the Sun’s corona – known as the coronal heating problem.
Hahn and Savin analyzed data from the Extreme Ultraviolet Imaging Spectrometer onboard the Japanese satellite Hinode. They used observations of a polar coronal hole, a region of the Sun where the magnetic fields lines stretch from the solar surface far into interplanetary space. The findings were published on September 30th in the October 20th edition of The Astrophysical Journal.
To understand the coronal heating problem, imagine a flame coming out of an ice cube.
A similar effect occurs on the surface of the Sun. Nuclear fusion in the center of the Sun heats the solar core to 15 million degrees. Moving away from this furnace, by the time one arrives at the surface of the Sun the gas has cooled to a relatively refreshing 6000 degrees. But the temperature of the gas in the corona, above the solar surface, soars back up to over one million degrees. What causes this unexpected temperature increase has puzzled scientists since 1939.
Two dominant theories exist to explain this mystery. One attributes the heating to the loops of magnetic field which stretch across the solar surface and can snap and release energy. Another ascribes the heating to waves emanating from below the solar surface, which carry magnetic energy and deposit it in the corona. Observations show both of these processes continually occur on the Sun. But until now scientists have been unable to determine if either one of these mechanisms releases sufficient energy to heat the corona to such high temperatures.
Hahn and Savin’s recent observations show that magnetic waves are the answer. The advance opens up a realm of further questions; chief among them is what causes the waves to damp. Hahn and Savin are planning new observations to try to address this issue.
This research has been supported by the National Science Foundation Division of Atmospheric and Geospace Sciences through the Solar, Heliospheric and Interplanetary Environment program.
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“Two dominant theories exist to explain this mystery”
No, no, no they’re doing this all wrong. When there are more than 2 theories to explain a phenomenon than you take a vote to see which is most popular. That idea wins and then all alternative ideas must be shouted down.
Climate “science” is the only science that is settled and was settled by concensus and relies on models. All the other sciences are open to question, experiment, revision, and validation. So which is the real science and why are we spending so much money on something that is NOT scientifically backed. Don’t ask the believers. They get cranky and resort to names and you all know what that name is. Its a pleasure to real actual science.
The temperatures rise from thousands of degrees K to millions within a single Transition Region at 2000 km above the photosphere.
http://folk.uio.no/gardini/transgraph.gif
Oh, good…when I teach about the sun in a few weeks I can casually interject this info as if I knew it all along!
mkelly says: October 16, 2013 at 8:06 am
Does the “over one million degrees” corona (sun’s atmosphere) heat the surface of the 6000 degree surface?
Despite the million degree temperature, there isn’t much heat in the corona. There really isn’t much of anything in the corona.
The sun’s visible surface density is about a thousandth of our sea level air density, and the corona is eleven orders of magnitude less dense than the sun’s surface. That’s far less than the vacuum inside a tokamak fusion reactor.
Object can and do, in isolation, emit a magnetic field.
Objects in isolation can not, as far as I am aware not emit an electrostatic field, but be one part of a pair of ‘conductors’ that can have a difference in electrical charge between them.
IE a capacitor has a measurable electrostatic field when charged up.
Charging of a capacitor is the temporary removal of electrons combined with the insertion of the same parcel of electrons into the opposite plate.
Move one plate to another continent, there would be no measurable electrostatic effect or capacitance.
If the sun or other astronomical body has a net positive or negative charge, this can only be, if there is a counter balancing charge in an adjacent body.
john robertson says: “Interesting, do the fluctuations in magnetic field strength, cause similar effects on earth?”
Maybe. http://image.yaymicro.com/rz_1210x1210/0/9cc/as-above-so-below-9ccd8f.jpg
Bob Mount says:
October 16, 2013 at 9:47 am
“What a pity that Climate “Science” isn’t as open and above board as real science, such as Astro-physics!”
Is that the study of the properties of the Jetson’s dog?
Lester Via says: “The earth’s exosphere also gets very hot (around 1500 K). I always assumed this will happen wherever a planet’s upper atmosphere gets so thin that molecular collisions are very rare, allowing individual, gravitationally bound, gas molecules to acquire considerable energy from being struck by a large number of solar UV photons between collisions. The temperature equilibrium achieved would be determined by photon flux, gravity, and the escape velocity of the gas molecule species. If my assumptions are incorrect, what is the current explanation of the temperature of our exosphere and why isn’t the same mechanism responsible for heating the sun’s corona?”
The thermosphere may be much more interesting. I often speculate that it functions like a grid in a vacuum tube, producing effects much greater than its low density would predict. It is true, however, that the odds are against any one photon passing directly through the thermosphere without striking something. It’s very tenuous, but it’s also very thick, and its thickness varies significantly with solar UV influx. Does that apply to the exosphere, as well?
David Thomson says:
October 16, 2013 at 8:54 am
They are finally on to the true nature of fusion reactions. The reason for the high temperature is the generation of new protons via a process similar to the Casimir effect
and
October 16, 2013 at 8:59 am
Interesting observation. Could the existence of observed LENRs be evidence that most of known physics is wrong?
Eh? This is new to me. Please cite some references.
How exactly can a Nuclear Reaction create magnetism ?
Surely not by the uniform movement or flow of electrons?
“Shirley not …”
.
meemoe_uk says:
The sun’s corona was explained by Langmuir in the middle of the 20th century. The plasma around the sun has a pinched galactic current running thru it, which makes it hot. But then just as now the dogma amongst astronomers was that electricity doesn’t exist in space so Langmuir’s explanation was ignored. etc
Well said.
Dr. Peter Hagelstein of MIT earlier this year in a series titled “Cold Fusion 101” covering a wide range of subjects/topics back to Pons and Fleischmann up to present day?
.
Moving charges create magnetic fields. Magnetic fields make charges move. That is how electromagnetism works. If you have a number of moving charges (plasma) and they are heating up, you can bet there is a magnetic field that is causing it.
thks Robertvd
and what I was saying shows in the comments here aswell!
plp here in the comments looking for explanations for the corona will consider Low Energy Nuclear reactions and exotic versions of the Casimir effect but they won’t consider such elementary 19th century physics such as heating by electric current.
Very interesting, I’ve been studying up on Ultraviolet radiation lately too, My current thinking is when UV reaches the earth or collides with a planet it slows down and releases its energy as heat. Solar Magnetic –> UV –> Heat –> IR. Thats global warming and cooling solved. It also works for ozone too, Solar Magnetic –> UV –> Ozone –> Heat –> IR.
Physics Prof. Yeong E. Kim, of Purdue University
If a magnetic field extends to interstellar space, then it must be powered by electric currents coming from interstellar space. The corona is so hot because the sun is powered by interstellar electric currents.
http://electric-cosmos.org/sun.htm
Two words, glow discharge.
thank you meemoe_uk! at least one WUWT follower shows to have some understanding of the sun’s structure that takes electricity into account and disagrees with the centenial self-contradictory nuclear furnace obsession.
It seems as though the internal fusion theory is about to join the flat earth theory…
I have a theory thats even more far out then the afore mentioned ones…
Aether Battery Iron Sun Theory
http://www.thunderbolts.info/forum/phpBB3/viewtopic.php?f=10&t=4592
A number of different solar theories that we discuss.
http://qdl.scs-inc.us/?top=4741-4760-5079-9484-9840-8919-6961-9927
Brant
6000 Degrees – Pah that’s Nothing !
As everybody knows the EARTH’s CORE is MILLIONS of DEGREES
“The observations help to answer a 70-year-old solar physics conundrum about the unexplained extreme temperature of the Sun’s corona – known as the coronal heating problem.”
Clearly its the sun people and their SUVs.
Why all this fuss about the sun? It’s got nothing to do with us, has it?