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View Full Version : Hinode Discovers the Sun's Hidden Sparkle



Fraser
2007-Dec-22, 01:00 AM
Blinking spots of intense light are being observed all over the lower atmosphere of the Sun. Not just in the active regions, but in polar regions, quiet regions, sunspots, coronal holes and loops. These small explosions fire elegant jets of hot solar matter into space, generating X-rays as they go. Although X-ray jets are known [...]

More... (http://feeds.feedburner.com/~r/universetoday/pYdq/~3/204349138/)

GOURDHEAD
2007-Dec-24, 03:38 PM
From the linked article:

The Sun is different. Through interactions near the surface of the Sun between plasma and magnetic flux (a field known as "magnetohydrodynamics" – magneto = magnetic, hydro = fluid, dynamics = motion: "magnetic-fluid-motion" in plain English, or "MHD" for short), MHD waves are able to propagate and heat up the plasma. The MHD waves under scrutiny are known as “Alfvén waves” (named after Hannes Alfvén, 1908-1995, the plasma physics supremo) which, theoretically, carry enough energy from the Sun to heat the solar corona hotter than the solar surface. The one thing that has dogged the solar community for the last half a century is: how are Alfvén waves produced? Solar flares have always been a candidate as a source, but observation suggested that there wasn't enough flares to generate enough waves. But now, with advanced optics used by Hinode, many small-scale events appear to be common… bringing us back to our X-ray jets…The method of observing the second law of thermodynamics seems to exclude ordinary em radiation, convection and conduction---even the law itself. So the transfer of the required energy must somehow be almost purely magnetic with little help from the electric field (although this can not be ruled out) where the intense ionization at and below the sun's surface imparts energy to the magnetic fields via time variation of intensity which releases this energy to the ionization present in the atmosphere of the sun via some "receiver resonance" property of the sun's atmosphere. This may suggest that in some hyper-extrapolated way the sun's magnetic field may possess excitation state rate changes to which the Earth's magnetic field and atmosphere respond resonantly on occasional intervals in which energy is transferred to the Earth's atmosphere significantly changing its temperature.

Has anyone analyzed the components of the particles ejected from the sun sufficiently to quantify the solar wind constituents? What, besides hydrogen, do we get?

iantresman
2007-Dec-25, 04:09 PM
So the transfer of the required energy must somehow be almost purely magnetic with little help from the electric field (although this can not be ruled out) where the intense ionization at and below the sun's surface imparts energy to the magnetic fields via time variation of intensity which releases this energy to the ionization present in the atmosphere of the sun via some "receiver resonance" property of the sun's atmosphere. [..]

Has anyone analyzed the components of the particles ejected from the sun sufficiently to quantify the solar wind constituents? What, besides hydrogen, do we get?

I thought magnetic fields could only store energy, not transfer it?

The Solar Wind consists of mainly free electrons and protons, which are as distinct from hydrogen, as water is distinct from a mixture of hydrogen and oxygen gases.

antoniseb
2007-Dec-25, 04:44 PM
I thought magnetic fields could only store energy, not transfer it?
Hmmm. How can they be considered to be storing energy if they can't transfer it somehow? Is that like write-only-memory, a kind of energy black hole? I wonder how mag-lev trains work if the magnetic field can't transfer energy. Gee, now that I think about it the dynamos that provide my electric power use magnetic fields to transfer energy. In fact every way that we can ever detect a magnetic field involves the transfer of energy. What the heck were you thinking?

iantresman
2007-Dec-25, 09:58 PM
Hmmm. How can they be considered to be storing energy if they can't transfer it somehow? Is that like write-only-memory, a kind of energy black hole? I wonder how mag-lev trains work if the magnetic field can't transfer energy. Gee, now that I think about it the dynamos that provide my electric power use magnetic fields to transfer energy. In fact every way that we can ever detect a magnetic field involves the transfer of energy. What the heck were you thinking?

Well, in a maglev, contiguous coils are powered-up, and then powered down, the magnetic field that is generated is not doing any transferring of energy. Isn't it the associated electric currents that transfer the energy? And magnetic energy can be converted to kinetic energy, and again it is the latter that does the transferring.

dgavin
2007-Dec-26, 03:43 PM
Well, in a maglev, contiguous coils are powered-up, and then powered down, the magnetic field that is generated is not doing any transferring of energy. Isn't it the associated electric currents that transfer the energy? And magnetic energy can be converted to kinetic energy, and again it is the latter that does the transferring.

Take two permanent magnets, turn them so the same charge is facing each other, then push one of them to the other and watch the other is pushed away.

That is a transfer of energy via magnetic fields.