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Knowledge is a curse, but ignorance is worse |
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It seems to me that the low density of those arcs qualifies them mostly as 'excited gas' than 'solid body'. Maybe someone could clarify this question... |
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The Sun's photosphere approximates a black body. The light it
emits approximates blackbody radiation. That is, a continuous spectrum, with intensity at different wavelengths dependant on temperature. The intensity of a blackbody spectrum at any wavelength, over the entire continuum, is given by Plank's radiation law. The peak wavelength of that intensity curve is given by the simpler Wien's displacement law. The Sun's photosphere is hottest at the bottom and cooler at the top. The chromosphere, above the photosphere, is even cooler. Cooler ions in and above the photosphere absorb some of the emitted blackbody radiation at specific wavelengths. The result is dark lines in the otherwise continuous spectrum: http://www.noao.edu/image_gallery/images/d5/suny.jpg Different ions absorb different wavelengths, and each different ion absorbs many specific wavelengths, so there is a very large number of dark lines in the Sun's spectrum. The image above shows just the visible light part of the spectrum. There are similar lines in the infrared, ultraviolet, and X-ray portions of the spectrum. If the ions are hotter, rather than cooler, they can emit more light than they absorb, causing bright lines instead of dark lines. Ions in the Sun's upper atmosphere are often heated by extremely powerful magnetic fields to very high temperature, causing them to emit light in specific bright lines. The higher the temperature, the shorter the wavelength of the specific lines which are bright. Wavelengths which are shorter or longer than those specific wavelengths will have dark lines. Emissions given off by the Sun's photosphere, a lightbulb, a burning candle, your body, and an ice cube all resemble blackbody curves fairly closely. The sun's chromosphere, emission nebulae, fluorescent lights, neon lights, LEDs, lasers, dental X-ray machines, TV screens, and computer monitors all give off light with spectral curves completely unlike blackbody curves, instead conststing mostly of bright line emission at specific wavelengths. That is what you see in the narrow-passband images from the TRACE spacecraft: Mostly light from bright-line emission, plus some light from blackbody emission at the same wavelength. What has confused you is the fact that bright-line emission does not occur at a specific wavelength if the temperature is too high. You are attempting to ascribe a property of blackbody emission to bright-line emission. -- Jeff, in Minneapolis
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http://www.FreeMars.org/jeff/ "The other planets? Well, they just happen to be there, but the point of rockets is to explore them!" -- Kai Yeves |
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![]() IMO, you also just gave the one line answer as to why Lockheed has this labeled backwards, that blue background is 6000K. Let me try this purely from a gas model perpective so you understand my motives here and why I think this is so critically important. The surface of the penumbral filaments has been measured at 6000K. That is the average temp of the "surface" of the photosphere. Somewhere deep in the core of the sun, a magnetic flux occurs and sends a streaming column of superheated plasma that rises through the surface of the photosphere and sometimes far into the corona. Whatever the processes in play that bring that superheated plasma through the penumbral filaments, that superheated column comes from below the photosphere. The reason we know the coronal loop has superheated plasma in it, is because it emits photons that are consistent with very high temperatures. These superheated columns of plasma pump huge amounts of heat into the sun's outer atmospheres, and even pick up some of that heat from the corona, if they rise that far. We can even see the three dimensional rise of this plasma column in the composite image from Yohkoh/Trace. In the lower regions, the base of the coronal loop is relatively cool, and relatively invisible to Yohkoh. As the superheated column reaches the corona, it picks up a lot of heat, and the plasma glows in x-ray that Yohkoh sees quite easily. So why is this so important that I would question Lockheed? It strikes to the very heart of the placement problem Lockheed has with the transition layer IMO. Alexander Kosovichev's work suggests that about 4800km below the surface of the photosphere, there is a distinct layer with a temperature/density change, where sound begins to travel much faster than it does through the first 4800km of the photosphere. We know this from heliosciesmology, and I trust Dr. Kosovichev's work. I'm impressed with it in fact. I trust that this sound transition layer exists at this location. If this superheated column of plasma is the heat source and rising through the photosphere, the Lockheed has this image backwords. The green plasma columns themselves are absolutely a higher temperature the then photosphere they are rising through, and a much higher temperature than the chromosophere as well. It is likely that the heat from these superheated columns of plasma are what pump heat into the corona and help heat the plasma one it reaches the corona. So how does all this apply? That blue area is dark in the original image because it's the outer photosphere. Several columns of superheated plasma are rising from the transition layer, through the photosphere, into the corona, where the columns glow in x-ray. The columns however are at a much, much, much higher temperature than anything else around it until it reaches the corona. Even then it is not clear how much of the heat originate from the coronal loops and simply ends up in the corona to begin with. The implication here is that the coronal loops, these superheated columns of plasma are much hotter the most of the medium they traverse. That Trace/Yohkoh image is increadibly revealing IMO as it shows the layer where x-rays are visible very clearly and shows a cooler plasma region below. Lockheed missed the boat here IMO since the blue areas are not superheated plasma, but are dark to both satellites. They are the visible photosphere and chromosphere. This is critically important IMO because it suggests that the transition layer is not above the photosphere, but underneath it. That transition layer we see at 4800km is where see these superheated columns originate, far below the photosphere. The rise up, through the photosphere and into the outer regions where Yohkoh sees the x-ray energy from these columns. You of course explained why Lockheed is wrong in a single sentence. I actually liked your explanation better, but I wanted to explain the significance of this image from my perspective, and why I believe it is critical. It has very important ramifications for the gas model. If that transition layer is below the photosphere, then the implications for the gas model must also be profound. The work of Dr. Kosivichev strongly suggests the transition layer is beneath the visible photosphere, not above it IMO. Last edited by Michael Mozina; 06-October-2005 at 01:57 PM. Reason: gas model consistency and spelling |
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http://news.bbc.co.uk/1/hi/sci/tech/1641599.stm |
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More than that, Lockeed says that their "image shows Active Region 8939 near the central meridian" which apparently is not conected with any sunspot. And Maksutov has a very good point; if you want to adress other issues please do it in an appropriate thread. |
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If the iron in the dark areas was really a million degrees like the loop, then the backround would also emit a LOT MORE photons than the coronal loops. That is not what we see. We see a cold photosphere and hot coronal loops. Quote:
In the original image, why is the background dark, if it is hotter than the brightest areas of coronal loops, and why is it also invisible to Yohkoh? |
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Just so we're all clear on what I'm doing ... this thread has now moved way, way beyond answering a question (the question was, in fact, answered), and has become a discussion of Michael's idea (or, rather, his interpretation of certain jpg images in the public domain).
So, off to ATM it goes. I will also be locking the main thread discussing Michael's idea there. |
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In addition, your cherry-picking of (rather meager) supporting data and selective avoidance of relevant questions don't belong in either of the two fora. Note: It appears I was composing this reply while Nereid was posting about the not unanticipated move of the thread. One day I'll learn to type faster!
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Please say we're through playing hopscotch with the threads? [grin]
MOZINA: http://edition.cnn.com/2002/TECH/sp....age/index.html I personally believe that iron is in "great" abundance. Hydrogen is also in great abundance and is a byproduct of the stars. I am suggesting that mostly the sun is iron and heavy elements. There is probably a layer of Xenon plasma in there somewhere, and I have no idea as to its density or temperatures on the inside. Overall however, most of a sun looks to be iron. There is a lot of hydrogen as well, but only because that is essentially what stars "exhale". The link is to an article that says there is more iron that we previously thought in the early universe, so maybe the universe is older than we think. It does not say anything in comparison to the amount of hydrogen in the early universe or even now. It says nothing about how much iron was thought to be in those clouds before. If the ratio of iron to hydrogen atoms in the ISM was estimated at 1:10,000 before, and then you triple it, it become 3:10,000. Not exactly iron abundant. This is qualitative data (words), not quaNTitative data (numbers). Words are hard to check for accuracy, thats why we ask for numbers instead. MOZINA: I am first of all puzzled by the your concept of "embedding" a fast moving stream of mostly iron particles into a predominantly hydrogen cloud. It seems to me like there is little or no mathematical evidence to support a relatively thin cloud of hydrogen would capture the iron and survive the shockwaves of a supernova. I do not grasp why you put so much faith in the idea that a mostly hydrogen cloud is going to stop and capture a supernova fragment wizzing by at several thousand miles an hour. It doesn't work the same way as a bullet getting imbedded in a sand bag. It's gravity at work, not friction. Gravity isn't affecting one atom of iron or hydrogen at a time. The entire mass cloud, bigger but less dense than the solar system, acts like a single gravitational body. Even hydrogen has a big gravitational field when it is that size. Particles from supernova will get swept into them because the mass of the incoming particles is far less than the mass of the cloud, since they left a supernova light-years away, they have spread out and become thin and dispersed as per the inverse square law. Also, I answered your question on the solar quakes. I believe it is posted here in this thread. But the main focus of this should be as Tim put it. We must get the biggest problems, the fundamentals, established as right or wrong before trying to nit pick any details. If the fundamental laws say it is impossible, the details are worthless.
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My son is my universe. |
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Last edited by Michael Mozina; 06-October-2005 at 05:12 PM. Reason: fixed mute to moot. Bad habits die hard I guess... |
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In the other composite image, you can see the coronal loops emitting green light from below the plasma layer, and we see it also rising through the plasma layer. If the corona was the hottest part, rather than the heated plasma column, the heat would show up one or more of these frequencies. It's not there. Quote:
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