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Last Post 3/3/2005 2:54 PM by  Terry Kucera
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3/3/2005 11:44 AM

    Sandra S

    Hi, We were looking at the NASA/Soho site. Why are some pictures of the Sun funny looking in color? There's also one that was blue, with a bunch of sparkle's in it, and a bright one on the right side?


    Terry Kucera



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    3/3/2005 2:54 PM
    Hi Sandra

    I work for SOHO, so I guess I should answer this one!
    The pictures you see of the Sun in funny colors are probably the ones from our ultraviolet telescope, EIT. People can't actually see ultraviolet light, so the colors are all false. However, to keep things straight we show different colors (wavelengths) of ultraviolet light in different colors of visible light (orange, blue, green, and yellow-ish).

    I think the blue one you are describing is probably one of the LASCO coronagraph images. The the instrument producing these images shows the Sun's outer atmosphere, the corona, by covering up the Sun's bright disk - essentially creating an artificial solar eclipse.
    These images _are_ of visible light, but the colors are still false. We color them 1) because it looks nice :-) and 2) because, again, it helps us tell apart images from our different coronagraphs (we have red images too, that show an area closer into the Sun).
    Anyway, the bright spot to the right with the horizontal streak through it is actually the planet Venus. We can see the planets when they pass close to the Sun.
    You can also see the stars in the coronagraph images. If you look at the movies you sometimes see small flashes of light. these are particles hitting the detector on the telescope. I think those might be the "sparkles" you mention.

    In case anyone else reads this, the web page I am looking at is
    http://sohowww.nascom.nas...realtime-images.html
    which shows SOHO's latest images of the Sun

    Terry


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