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#2111
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On Sun, 23 Sep 2007 12:33:14 +0100, "George Dishman"
wrote: "Dr. Henri Wilson" HW@.... wrote in message .. . On Fri, 21 Sep 2007 01:08:23 +0100, "George Dishman" wrote: "Henri Wilson" HW@.... wrote in message Of course it can Henry, that's the point. Suppose we take an arbitrary figure of 10 light years for the speed equalisation distance in the space surrounding some star. To get 1.5 mag variation you need a critical distance of 13.35 light years. To get 9 mag that needs to be 10.0025 light years, just a 25% increase in the peak orbital acceleration. What the hell are you talking about? Check the numbers, see for yourself. For a given value of peak acceleration, draw a graph of peak variation as a function of distance. What do you think my program does? If you think it can tell you the above results, use it. Tell me what distance as a percentage of (c^2/a) you get a variation peak variation of 8 magnitudes (peak-to-peak will be about 0.75 magnitudes more). Tell me whether you would get multiple images if the distance were 1% greater. If that is at an inclination of 45 degrees, would we see multiple images if it were 1 degree closer to edge-on? It never gets to that point. I have suggested before that the unification rate in any defineable volume of space is dependent on the difference between the actual light speed and the natural equilibrium speed in that region. Your numbers are completely wrong... Then use your program and post your alternatives. You can use it. It's quite user friendly now. www.users.bigpond.com/hewn/variables.exe George Henri Wilson. ASTC,BSc,DSc(T) www.users.bigpond.com/hewn/index.htm |
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On Fri, 21 Sep 2007 15:46:12 +0100, "George Dishman"
wrote: "Henri Wilson" HW@.... wrote in message .. . On Wed, 19 Sep 2007 21:17:09 +0100, "George Dishman" wrote: "Henri Wilson" HW@.... wrote in message ... On Mon, 17 Sep 2007 19:33:27 +0100, "George Dishman" wrote: "Henri Wilson" HW@.... wrote in message om... [I wrote:] Your model consists of two equations: v = u+c and dv/ds =(c/n - v)/R Neither has any oscillatory term. ![]() Now write the equation for the wave in a moving organ pipe..whilst it is producing sound... Why would I do that? It isn't a solution to either of the equations so not part of your theory. You obviously don't understand my photon theory.. You don't have a photon theory, you only talk about them as bursts of classical waves but your equations do not produce photons. See my description of your 'EM' program for an analysis and then think what you could do to your equations to make such a pattern self sustaining during propagation. I don't think it is possible. See my reply to Ghost in the other thread. I haven't seen a new message from you to him since this was posted so you'll need to give me a link or summarise. "Gray atmosphere" I believe is the term in this field, but Kirchoff's Law still applies and since the opacity increases with depth you still cannot see through to deeper layers beyond the photosphere. But you just asked how long it took light from the sun's core to reach the surface. If t reaches the surface at all, surely you can 'see' it. You see the surface from which it was last emitted. Think of an opaque film with light shining on it. The film heats up and emits black-body radiation so a black plastic film with sunlight might glow at 300K even though the spectrum illuminating it is over 5000K. You can still feel the warmth but there will be a slight delay if a shaow passes over it. Try it with a black plastic bag in a frame in your back garden. Not convincing.... Not meant to be, simply an analogy to aid understanding. For proof, you need to calculate the mean free path. While on that subject. I once decided to heat my computer room in winter by hanging a black plastic curtin over the large north facing window ( I live in OZ). This worked well, acting as both a re-radiator and a double insulator...The room warmed very efficiently and was dark enough for me to see the screen. There was only one problem...after several weeks, I started to get a sore throat whenever I sat there for long. I finally woke up to the fact that the plastic was slowly decaying and giving off what was probably a pretty deadly gas...It didn't kill me but I wouldn't recommend it to anyone else. Nasty. I later rigged up a similar curtain using sheet metal and achieved the same result....plenty of warmth with little bright sunlight... Nice. Now imagine a material which is slighly translucent but so thick no light gets through, just the heat. You might be able to see 2mm into it but it is 100cm thick. That's how the surface of the Sun behaves, except that in addition it is more transparent near the surface and gets denser with depth, say 1cm of transparent before you get to the 1mm translucent layer. The far side is hot where the Sun hits it, the near side is cooler because of the insulating effect of the material, and looking into the surface you see a small temperature gradient from about 11 mm into the material. Yes of course... but outward energy flow has to be consistent... I once had a job taking very fine photos of the sun, mainly in the H red. The edges of the ball were quite sharp. However, that doesn't mean a significant thick tansparent layer does not exist....and that layer emits plenty of light. George Henri Wilson. ASTC,BSc,DSc(T) www.users.bigpond.com/hewn/index.htm |
#2113
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On 23 Sep, 22:09, HW@....(Henri Wilson) wrote:
On Sun, 23 Sep 2007 12:33:14 +0100, "George Dishman" wrote: "Henri Wilson" HW@.... wrote in messagenews:kigbf317ahrqpdeknk5lrk0rsv0t7oc9f3@4a x.com... On Fri, 21 Sep 2007 01:08:23 +0100, "George Dishman" wrote: "Henri Wilson" HW@.... wrote in message restoring the subject from which Henry is trying to run away On Wed, 19 Sep 2007 21:36:10 +0100, "George Dishman" wrote: "Henri Wilson" HW@.... wrote in message m... On Mon, 17 Sep 2007 19:23:54 +0100, "George Dishman" wrote: Multiple images start at what I called the critical distance given by d = c^2/a where a is the peak radial acceleration. Variation of 1.5 mags means a ratio of 4:1 in luminosity which means the speed unification distance is about 75% of the critical distance. Other values are Percentage of Mag 1:n critical 1 2.5 60.19% 1.5 4.0 74.88% 2 6.3 84.15% 3 15.8 93.69% 4 39.8 97.49% 5 100.0 99.00% 6 251.2 99.60% 7 631.0 99.84% 8 1584.9 99.94% 9 3981.1 99.97% Isn't it magical how we see variations of up to 9 mags in some stars yet NEVER see multiple images. It is true some stars are reported to vary by 7-9 mags. This cannot be explained solely by c+v effects. Of course it can Henry, that's the point. Suppose we take an arbitrary figure of 10 light years for the speed equalisation distance in the space surrounding some star. To get 1.5 mag variation you need a critical distance of 13.35 light years. To get 9 mag that needs to be 10.0025 light years, just a 25% increase in the peak orbital acceleration. What the hell are you talking about? Check the numbers, see for yourself. For a given value of peak acceleration, draw a graph of peak variation as a function of distance. What do you think my program does? If you think it can tell you the above results, use it. Tell me what distance as a percentage of (c^2/a) you get a variation peak variation of 8 magnitudes (peak-to-peak will be about 0.75 magnitudes more). Tell me whether you would get multiple images if the distance were 1% greater. If that is at an inclination of 45 degrees, would we see multiple images if it were 1 degree closer to edge-on? It never gets to that point. Stop ducking the issue Henry, you claimed my numbers were wrong so prove it, put up or shut up. Your numbers are completely wrong... Then use your program and post your alternatives. You can use it. ... Why, don't you know how? I think you are so hopeless that even this trivial arithmetic is beyond you, but you claimed my numbers were wrong so it is up to you to back that up, I'm not going to do it for you. Oh and if your program gives something other than those values, you will still need to prove it is your code that is right and not my numbers, IMO your code is highly suspect. Bear in mind the numbers are peak, not peak-to-peak which I think is what your program usually produces as the summary. George |
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On Mon, 24 Sep 2007 05:53:18 -0700, George Dishman
wrote: On 23 Sep, 22:09, HW@....(Henri Wilson) wrote: On Sun, 23 Sep 2007 12:33:14 +0100, "George Dishman" wrote: "Henri Wilson" HW@.... wrote in messagenews:kigbf317ahrqpdeknk5lrk0rsv0t7oc9f3@4a x.com... On Fri, 21 Sep 2007 01:08:23 +0100, "George Dishman" wrote: "Henri Wilson" HW@.... wrote in message restoring the subject from which Henry is trying to run away On Wed, 19 Sep 2007 21:36:10 +0100, "George Dishman" wrote: "Henri Wilson" HW@.... wrote in message om... On Mon, 17 Sep 2007 19:23:54 +0100, "George Dishman" wrote: Multiple images start at what I called the critical distance given by d = c^2/a where a is the peak radial acceleration. Variation of 1.5 mags means a ratio of 4:1 in luminosity which means the speed unification distance is about 75% of the critical distance. Other values are Percentage of Mag 1:n critical 1 2.5 60.19% 1.5 4.0 74.88% 2 6.3 84.15% 3 15.8 93.69% 4 39.8 97.49% 5 100.0 99.00% 6 251.2 99.60% 7 631.0 99.84% 8 1584.9 99.94% 9 3981.1 99.97% Isn't it magical how we see variations of up to 9 mags in some stars yet NEVER see multiple images. It is true some stars are reported to vary by 7-9 mags. This cannot be explained solely by c+v effects. Of course it can Henry, that's the point. Suppose we take an arbitrary figure of 10 light years for the speed equalisation distance in the space surrounding some star. To get 1.5 mag variation you need a critical distance of 13.35 light years. To get 9 mag that needs to be 10.0025 light years, just a 25% increase in the peak orbital acceleration. What the hell are you talking about? Check the numbers, see for yourself. For a given value of peak acceleration, draw a graph of peak variation as a function of distance. What do you think my program does? If you think it can tell you the above results, use it. Tell me what distance as a percentage of (c^2/a) you get a variation peak variation of 8 magnitudes (peak-to-peak will be about 0.75 magnitudes more). Tell me whether you would get multiple images if the distance were 1% greater. If that is at an inclination of 45 degrees, would we see multiple images if it were 1 degree closer to edge-on? It never gets to that point. Stop ducking the issue Henry, you claimed my numbers were wrong so prove it, put up or shut up. George, use a computer program ....and stop wasting your time with equations. Your numbers are completely wrong... Then use your program and post your alternatives. You can use it. ... Why, don't you know how? I think you are so hopeless that even this trivial arithmetic is beyond you, but you claimed my numbers were wrong so it is up to you to back that up, I'm not going to do it for you. Oh and if your program gives something other than those values, you will still need to prove it is your code that is right and not my numbers, IMO your code is highly suspect. Bear in mind the numbers are peak, not peak-to-peak which I think is what your program usually produces as the summary. George, I'm way ahead of you on this... You don't even understand the basics... George Henri Wilson. ASTC,BSc,DSc(T) www.users.bigpond.com/hewn/index.htm |
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On 24 Sep, 23:19, HW@....(Dr. Henri Wilson) wrote:
On Mon, 24 Sep 2007 05:53:18 -0700, George Dishman wrote: On 23 Sep, 22:09, HW@....(Henri Wilson) wrote: On Sun, 23 Sep 2007 12:33:14 +0100, "George Dishman" wrote: "Henri Wilson" HW@.... wrote in messagenews:kigbf317ahrqpdeknk5lrk0rsv0t7oc9f3@4a x.com... On Fri, 21 Sep 2007 01:08:23 +0100, "George Dishman" wrote: "Henri Wilson" HW@.... wrote in message restoring the subject from which Henry is trying to run away On Wed, 19 Sep 2007 21:36:10 +0100, "George Dishman" wrote: "Henri Wilson" HW@.... wrote in message om... On Mon, 17 Sep 2007 19:23:54 +0100, "George Dishman" wrote: Multiple images start at what I called the critical distance given by d = c^2/a where a is the peak radial acceleration. Variation of 1.5 mags means a ratio of 4:1 in luminosity which means the speed unification distance is about 75% of the critical distance. Other values are Percentage of Mag 1:n critical 1 2.5 60.19% 1.5 4.0 74.88% 2 6.3 84.15% 3 15.8 93.69% 4 39.8 97.49% 5 100.0 99.00% 6 251.2 99.60% 7 631.0 99.84% 8 1584.9 99.94% 9 3981.1 99.97% Isn't it magical how we see variations of up to 9 mags in some stars yet NEVER see multiple images. It is true some stars are reported to vary by 7-9 mags. This cannot be explained solely by c+v effects. Of course it can Henry, that's the point. Suppose we take an arbitrary figure of 10 light years for the speed equalisation distance in the space surrounding some star. To get 1.5 mag variation you need a critical distance of 13.35 light years. To get 9 mag that needs to be 10.0025 light years, just a 25% increase in the peak orbital acceleration. What the hell are you talking about? Check the numbers, see for yourself. For a given value of peak acceleration, draw a graph of peak variation as a function of distance. What do you think my program does? If you think it can tell you the above results, use it. Tell me what distance as a percentage of (c^2/a) you get a variation peak variation of 8 magnitudes (peak-to-peak will be about 0.75 magnitudes more). Tell me whether you would get multiple images if the distance were 1% greater. If that is at an inclination of 45 degrees, would we see multiple images if it were 1 degree closer to edge-on? It never gets to that point. Stop ducking the issue Henry, you claimed my numbers were wrong so prove it, put up or shut up. George, use a computer program .... Stop ducking Henry, you said my numbers were wrong but the truth is you haven't a clue how to produce them yourself. and stop wasting your time with equations. The equations told me the answers in seconds while you are incapable of working them out at all. You are incompetent at even trivial arithmetic, and the only use for the computer is to have it calculate the equation for you anyway (which is what I did with Excel of course). Your numbers are completely wrong... Then use your program and post your alternatives. You can use it. ... Why, don't you know how? I think you are so hopeless that even this trivial arithmetic is beyond you, but you claimed my numbers were wrong so it is up to you to back that up, I'm not going to do it for you. Oh and if your program gives something other than those values, you will still need to prove it is your code that is right and not my numbers, IMO your code is highly suspect. Bear in mind the numbers are peak, not peak-to-peak which I think is what your program usually produces as the summary. George, I'm way ahead of you on this... No Henry, you can't even do a simple sum, turning astronomical magnitudes into ratios and then taking a simple inverse. I'm surprised you got past primary school on this evidence! George |
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On 23 Sep, 21:15, HW@....(Dr. Henri Wilson) wrote:
On Wed, 19 Sep 2007 22:16:11 +0100, "George Dishman" wrote: "Henri Wilson" HW@.... wrote in message ... Incidentally, ANTU and MELIPAL are only 102m apart if you check the diagram, but the point remains, the inteferometer is still capable of detecting individual photons and intereference results from the _two_ telescopes. You are not making it clear whethr the result is a normal image or an interfrence pattern. All I would expect to get from this greater resolution is a normal image. The system was used to measure L Car. Using just one of the two telescopes, you get an image which is basically a point, the size of the imaged star will be less than the PSF (point spread function) of the scope which is set by the diameter of the dish. If you could make a reflector 100m across, that diffraction limit would be less than the image diameter so you could resolve the star as a disc. the system goes part way there by combining the light from the two telescopes. If the star were static, the interference would modify the detector output like putting a photocell at a fixed point in a Young's Slits experiment, say 50%. However, the earth rotates and as it does so it sweeps across the star so essentially the interference pattern is swept over the detector as the star's image appears to moves across the sky. That allows the contrast ratio between the dark and light fringes to be seen as a variation in the signal from the detector and the contrast ratio depends on the star's diameter. If as you claim, individual photons DO spread themselves out...or disperse.. as they travel, then this fact would give a litttle more information to work on in constructing a photon model. It doesn't really conflict with my traveling wave idea. It simply means the whole crossection becomes larger. You have to think of your diagram as a sort of cross section. The spherical wavefronts you mentioned would look like alternate red and blue umberellas if you did a 3D version of your program. ...but I cannot see how a gamma paticle can end up similarly dispersed.... Photons hit one atom on a detector but never that next to it. They usually behave like bursts of wavefronts in optical systems and zero-size particles in detectors. That is not an acceptible theory. It is not a theory of any kind Henry. A theory consists of a set of eqations that make quanititative predictions of observed measurable values. What I said is a statement of what is observed, any valid theory has to predict that behaviour. explain how you can get interference effects with single photon sources like dim stars. You don't seem to appreciate that many advanced telescopes work in this low photon rate mode these days. Well you can't produce an interference pattern that way. But they do Henry, a lot of astronomy is done that way now. Take your EM program, think of it like a string of umberellas and if one red umberella wavefront passing through one telescope arrives at the same time as another later red umberella wavefront via the other telescope then you get constructive interference. You have drawn the pattern along a 1D 'ray' and the wavefronts are normal to that but imagine what a 3D view would look like. Who's to say how wide it could be? The evidence is they cover the whole sphere at emission. Well I say the conclusions are a complete misinterpretation of the facts. What I have written above are the facts, it is up to you to interpret them. Photons only ever cause a single detection in a sensor (perhaps multiple electrons if avalanche technology is used) and individual photons are subject to all the normalrules of interference and diffraction. Regardless of your lack of understanding of that point, even with classical waves, it should be obvious that only the speed from x to y affects the relative phase at the detector provided the speed from the mirrors to the detector is the same in both cases. George, you are referring to a photon that acts over a distance of at least 120 metres and somehow creates fringes. Where does 'wavelength' come into this? You also said once before that the interference is cause byinteraction between photons emitted from the two sides of the star. No Henry, you said that. I said that was impossible because they are uncorrelated. I think you spend too much time inventing strawmen and forget what I really said. George, if the pattern is NOT caused by photons from both sides of the star, how can it possibly privide information about radius change? I explained that before. Photons(idividually) from one side of the star create a pattern of intensity. Photons from the other also create their own pattern, again behaving individually, but the patterns are displaced by a small amount, essentially the size of the "image" formed by the telescope. Because one is shifted relative to the other, the nulls don't occur in the same place which affects the contrast ratio of the fringe pattern. The actual analysis is much more complex, involving limb darkening and lots of other stuff but those are the basics. snip lots not commented I doubt if single photon that has traveled 1700 LYs will be detectable on both sides of a 600 metre circle. The longest baseline used by the GSI setup is 12400.5 km so photons have to be bigger than that :-) It is possible...but you wont produce any interference involving photons emitted from both sides of a star in this way. No Henry, you get interference when a single photon is received at both ends of the antenna and combined. If the path length difference is a multiple of the wavelength you get constructive interference as usual. That applies to each photon individually. The path length difference for the phtotn includes a term that depends on which side it came from since that slightly changes the angle of the wavefront since it is perpendicular to the line of site. George, no matter how you try to wriggle out, a single photon from a star cannot tell you anything about the star's radius. Of course not, as I told you before, it is the superposition of the displaced interference patterns that carries the information. Do you think I have all day... I don't think your have that much life left, but that's what proper models do, you can find the result all over the web. "How long does it take for light from the Sun's core to reach us?" they say it takes thousands of years.... Right, that's from the core. In Cepheids, most of that time is reaching the unstable region but it still takes some more time to reach the photosphere hence there is a lag. I don't accept that cepheids are really huff puff stars. Tough, the radius is observed to vary and the interferometric, photometric and integrated velocity measurements are all similar. I hope you are impressed George. No, ballistic theory is wrong as shown by Sagnac but I am pleased that you have learnt a little local astrophysics, that's what this game is all about ;-) Sagnac disproves SR. ... Don't waste your time with stupid word games, it would be better spent if you learned some schoolboy calculus. George |
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On 23 Sep, 22:18, HW@....(Dr. Henri Wilson) wrote:
On Fri, 21 Sep 2007 15:46:12 +0100, "George Dishman" wrote: much snipped as not addressed .... .. imagine a material which is slighly translucent but so thick no light gets through, just the heat. You might be able to see 2mm into it but it is 100cm thick. That's how the surface of the Sun behaves, except that in addition it is more transparent near the surface and gets denser with depth, say 1cm of transparent before you get to the 1mm translucent layer. The far side is hot where the Sun hits it, the near side is cooler because of the insulating effect of the material, and looking into the surface you see a small temperature gradient from about 11 mm into the material. Yes of course... but outward energy flow has to be consistent... Of course, typically the flow is analysed along a column. I once had a job taking very fine photos of the sun, mainly in the H red. The edges of the ball were quite sharp. First remember the 400km I quoted is vertically into the Sun at the centre. As you move towards the limb it becomes smaller as the light path is at a shallower angle. At this range even 400km would subtend a very small angle at the camera. However, that doesn't mean a significant thick tansparent layer does not exist.... Of course, the corona for example. and that layer emits plenty of light. Oops, no. You forgot Kirchofff's Law again, if it is really transparent it cannot emit at all. In practice both the outer layer just above the photosphere and the corona show spectral lines. The upper surface is cooler than the photosphere so they appear in absorption while the corona is hotter and the lines show as emission. What we have been discussing re temperature is the background continuum excluding the lines. George |
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On Tue, 25 Sep 2007 05:47:38 -0700, George Dishman
wrote: On 23 Sep, 21:15, HW@....(Dr. Henri Wilson) wrote: On Wed, 19 Sep 2007 22:16:11 +0100, "George Dishman" wrote: "Henri Wilson" HW@.... wrote in message ... ...but I cannot see how a gamma paticle can end up similarly dispersed.... Photons hit one atom on a detector but never that next to it. They usually behave like bursts of wavefronts in optical systems and zero-size particles in detectors. That is not an acceptible theory. It is not a theory of any kind Henry. A theory consists of a set of eqations that make quanititative predictions of observed measurable values. What I said is a statement of what is observed, any valid theory has to predict that behaviour. George, admit it. Nobody including you has much of a clue about the true nature of light. Well you can't produce an interference pattern that way. But they do Henry, a lot of astronomy is done that way now. Take your EM program, think of it like a string of umberellas and if one red umberella wavefront passing through one telescope arrives at the same time as another later red umberella wavefront via the other telescope then you get constructive interference. You have drawn the pattern along a 1D 'ray' and the wavefronts are normal to that but imagine what a 3D view would look like. Who's to say how wide it could be? The evidence is they cover the whole sphere at emission. Well I say the conclusions are a complete misinterpretation of the facts. What I have written above are the facts, it is up to you to interpret them. Photons only ever cause a single detection in a sensor (perhaps multiple electrons if avalanche technology is used) and individual photons are subject to all the normalrules of interference and diffraction. To get interference from two detectors spaced 100 metres apart requires coherence. If a single photon stretches right across then what you said above is wrong. A 100 m wide photon will strike more than one atom. Even YOU should see that. You also said once before that the interference is cause byinteraction between photons emitted from the two sides of the star. No Henry, you said that. I said that was impossible because they are uncorrelated. I think you spend too much time inventing strawmen and forget what I really said. George, if the pattern is NOT caused by photons from both sides of the star, how can it possibly privide information about radius change? I explained that before. Photons(idividually) from one side of the star create a pattern of intensity. Photons from the other also create their own pattern, again behaving individually, but the patterns are displaced by a small amount, essentially the size of the "image" formed by the telescope. Because one is shifted relative to the other, the nulls don't occur in the same place which affects the contrast ratio of the fringe pattern. The actual analysis is much more complex, involving limb darkening and lots of other stuff but those are the basics. It sounds as though all you are seeing is a fuzzy image of the star. No Henry, you get interference when a single photon is received at both ends of the antenna and combined. If the path length difference is a multiple of the wavelength you get constructive interference as usual. That applies to each photon individually. The path length difference for the phtotn includes a term that depends on which side it came from since that slightly changes the angle of the wavefront since it is perpendicular to the line of site. George, no matter how you try to wriggle out, a single photon from a star cannot tell you anything about the star's radius. Of course not, as I told you before, it is the superposition of the displaced interference patterns that carries the information.... I could just as easily carry information about varying light speed. Right, that's from the core. In Cepheids, most of that time is reaching the unstable region but it still takes some more time to reach the photosphere hence there is a lag. I don't accept that cepheids are really huff puff stars. Tough, the radius is observed to vary and the interferometric, photometric and integrated velocity measurements are all similar. ..they are willusions. I hope you are impressed George. No, ballistic theory is wrong as shown by Sagnac but I am pleased that you have learnt a little local astrophysics, that's what this game is all about ;-) Sagnac disproves SR. ... Don't waste your time with stupid word games, it would be better spent if you learned some schoolboy calculus. I know more about calculus than you do. I prefer to avoid it where possible. George Henri Wilson. ASTC,BSc,DSc(T) www.users.bigpond.com/hewn/index.htm |
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On Tue, 25 Sep 2007 05:57:48 -0700, George Dishman
wrote: On 23 Sep, 22:18, HW@....(Dr. Henri Wilson) wrote: On Fri, 21 Sep 2007 15:46:12 +0100, "George Dishman" wrote: much snipped as not addressed ... .. imagine a material which is slighly translucent but so thick no light gets through, just the heat. You might be able to see 2mm into it but it is 100cm thick. That's how the surface of the Sun behaves, except that in addition it is more transparent near the surface and gets denser with depth, say 1cm of transparent before you get to the 1mm translucent layer. The far side is hot where the Sun hits it, the near side is cooler because of the insulating effect of the material, and looking into the surface you see a small temperature gradient from about 11 mm into the material. Yes of course... but outward energy flow has to be consistent... Of course, typically the flow is analysed along a column. I once had a job taking very fine photos of the sun, mainly in the H red. The edges of the ball were quite sharp. First remember the 400km I quoted is vertically into the Sun at the centre. As you move towards the limb it becomes smaller as the light path is at a shallower angle. At this range even 400km would subtend a very small angle at the camera. However, that doesn't mean a significant thick tansparent layer does not exist.... Of course, the corona for example. and that layer emits plenty of light. Oops, no. You forgot Kirchofff's Law again, if it is really transparent it cannot emit at all. George, absorption is exponential. If the layer absorbs only 10% per 100 kms, about 36% will still pass through 1000 kms. The layer will have an emissivity 0 and will still radiate. In practice both the outer layer just above the photosphere and the corona show spectral lines. The upper surface is cooler than the photosphere so they appear in absorption while the corona is hotter and the lines show as emission. What we have been discussing re temperature is the background continuum excluding the lines. ....yes..and I have been pointing out that ADoppler can cause a considerable shift in the planck curve. George Henri Wilson. ASTC,BSc,DSc(T) www.users.bigpond.com/hewn/index.htm |
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On 25 Sep, 22:53, HW@....(Dr. Henri Wilson) wrote:
On Tue, 25 Sep 2007 05:57:48 -0700, George Dishman wrote: On 23 Sep, 22:18, HW@....(Dr. Henri Wilson) wrote: On Fri, 21 Sep 2007 15:46:12 +0100, "George Dishman" wrote: much snipped as not addressed ... .. imagine a material which is slighly translucent but so thick no light gets through, just the heat. You might be able to see 2mm into it but it is 100cm thick. That's how the surface of the Sun behaves, except that in addition it is more transparent near the surface and gets denser with depth, say 1cm of transparent before you get to the 1mm translucent layer. The far side is hot where the Sun hits it, the near side is cooler because of the insulating effect of the material, and looking into the surface you see a small temperature gradient from about 11 mm into the material. Yes of course... but outward energy flow has to be consistent... Of course, typically the flow is analysed along a column. I once had a job taking very fine photos of the sun, mainly in the H red. The edges of the ball were quite sharp. First remember the 400km I quoted is vertically into the Sun at the centre. As you move towards the limb it becomes smaller as the light path is at a shallower angle. At this range even 400km would subtend a very small angle at the camera. However, that doesn't mean a significant thick tansparent layer does not exist.... Of course, the corona for example. and that layer emits plenty of light. Oops, no. You forgot Kirchofff's Law again, if it is really transparent it cannot emit at all. George, absorption is exponential. If the layer absorbs only 10% per 100 kms, about 36% will still pass through 1000 kms. The layer will have an emissivity 0 and will still radiate. See the next paragraph: In practice both the outer layer just above the photosphere and the corona show spectral lines. The upper surface is cooler than the photosphere so they appear in absorption while the corona is hotter and the lines show as emission. What we have been discussing re temperature is the background continuum excluding the lines. There is no continuum emission from the 'transparent' layer but where there is a resonance and the opacity is higher at that specific frequency, we see absorption. ...yes..and I have been pointing out that ADoppler can cause a considerable shift in the planck curve. And I have been pointing that while it _could_, we know it _doesn't_, the actual shift is only 0.01% and such a small shift doesn't affect temperature determination. Note also that if the frequency shift were larger, it would no longer be a black body curve but in practice the shift is so small that is negligible. George |
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