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Can the gas model theory explain recent satellite observations?

  1. Apr 25, 2006 #1
    I am curious what specific gas model theories would be useful in explaining the consistent "patterns" we see in solar "running difference" and doppler images such as these:

    Trace running difference image:
    http://trace.lmsal.com/POD/movies/T171_000828.avi
    http://trace.lmsal.com/POD/TRACEpodarchive4.html

    This video spans more than an hour yet the "patterns" remain relatively fixed compared to the plasma activity at the surface of the photosphere where structures come and go every 8 minutes or so. Why aren't these structures showing any signs of differential rotation, or the boiling patterns that are typically seen in the plasma of the photosphere?

    Here is some background information and the supporting SOHO Doppler image that was put together by Alexander Kosovichev from Stanford:

    http://www.findarticles.com/p/articles/mi_m1571/is_n25_v14/ai_20884033
    http://thesurfaceofthesun.com/images/vquake1.avi
    [​IMG]

    I'm specifically curious about the angular structure we see under the wave to the left of the center of the wave. Why is that structure more "rigid" than the plasma that carries the wave? How is that structure holding it's angular shape as the wave passes over it?
     
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  3. Apr 25, 2006 #2

    SpaceTiger

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    The video you linked is two seconds long.
     
  4. Apr 25, 2006 #3
    That is actually quite true, but it also represents solar activity over more than an hour and a half. :smile:

    Compared to the granular patterns of the photosphere that sort of "boil" themselves out of existence every 8 minutes or so, that's nearly an eternity.

    There are also SOHO running difference images that show the same consistency of pattern over the span of many days.
     
    Last edited: Apr 25, 2006
  5. Apr 25, 2006 #4
    This image shows the movement that is typical in the granular cells of the photosphere over even relatively short timelines. There is a great deal more movement going on in the plasma of the photosphere than we see in the RD images using the iron ion filters of 171A, 195A, and 284A on the Trace and SOHO satellites.
     
  6. Apr 25, 2006 #5

    SpaceTiger

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    I'm afraid that's not particularly helpful. Could you be a bit more quantitative? For example, could you give the rotation rate of these features as a function of latitude and compare it to the expected differential rotation rate?
     
  7. Apr 26, 2006 #6

    Chronos

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    Looks like more of the same old [and thoroughly refuted] 'iron sun' proposition to me.
     
  8. Apr 26, 2006 #7
  9. Apr 26, 2006 #8

    SpaceTiger

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    That's right, and he's not permitted to discuss his theory on these fora (only in IR), but we are allowed to address questions about the mainstream model. If it's true that structures are rotating contrary to differential rotation, it will be interesting to explore how the mainstream model deals with it. I honestly find it hard to tell one way or the other from those PR videos.
     
    Last edited: Apr 26, 2006
  10. Apr 26, 2006 #9
    I can try to be a "bit" more quantitative, but Lockheed has not given me many details related to this image. I do believe the image in question covers more than an hour and a half, and potentially longer, depending on which specific images were used to subtract from. Unfortunately I didn't create this image personally, and Lockheed has not provided much in the way of specific details about this image to date.

    I'm also not sure a single rotational "number" tells us the "whole" picture, certainly not of both images. For instance, even though the "average" rotation in the photosphere might only be a few pixels over an hour and half timeline, the "boiling" affect is rather noticeable on a smaller scale. The plasma tends to move on a "per pixel" basis, with the "average" pixel drifting "x" amount over a give time at a given distance from the equator. At a smaller scale however, the "boiling" granular nature of the photosphere is reshaped regularly, and smaller "structures" tend to come and go in 8 minute intervals.

    The patterns in these RD and Doppler images are a bit more complex. While the lighting on the patterns in the RD image changes during the timeline in question, the patterns themselves remain in a pretty "fixed" relationship to one another. In other words the "lines" on the central structure remain pretty much in the same distance from one another at the start of the sequences as the are at the end of the sequence, even though the sequence includes a flare scenario that should cause quite a "blow out" in plasma. Even still, the patterns remain much more "rigid" in relationship to one another than we see in granular views of the photosophere.

    There are some mathematical specifics I can tell you about these images. The RD image spans from 11.87°S to 30.52°S. According to Lockheed's website, this image covers a timeline that is in excess of an hour. Based on the changes I see in the Lockheed image and comparing these changes to changes I see in the original FITS files, I would say this sequence is at least an hour and a half long. Depending on which images were used to subtract from, the whole sequence could span over two hours.

    The Doppler image is somewhat harder to quantify using simply differential rotation principles since there is a giant wave passing over the photosphere which has no affect on the angular structures seen below the photosphere.
     
  11. Apr 26, 2006 #10
    I will not attempt to explain these images using a Birkeland solar model or any other solar model. I am simply curious how the gas model would attempt to explain these images. Anyone interested in discussing these or any other solar images using a Birkeland solar model is welcome to join an ongoing discussion of these issues at Uplink at space.com.
     
  12. Apr 26, 2006 #11

    SpaceTiger

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    I don't see anything unusual in the images and, lacking information about how it was processed, it's kinda silly to consider it a challenge to the standard solar model. As such, there's nothing left to discuss here. If you wish to do a more detailed analysis of the images (for example, correlation functions, timing power spectra), feel free to submit your work to IR, but even that is probably a bad idea if you don't know how it was processed.
     
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