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    Re: A halo-like rainbow round the Sun: some sextant measurements.
    From: Tony Oz
    Date: 2017 May 17, 07:13 -0700

    Frank,

    Yes, it was just like the pictured, but only the left bright spot was visible then. I saw them before - several times, - some of them were symmetrical. But I did not have any angle-measuring tool with me and did not notice the colors order.

    Vaguely remembering the "42°" number of the usual rainbow - I expected this halo would be the same. So when I got just 20° - I re-checked the angle several times, it was definitely NOT equal to 22° (or 42° either) - unless I was mising the Sun's center through the denser mist there. Then I got an idea to measure the angular span of the rainbow sector itself - equaling to 0°20'' from red to violet.

    Regards,

    Tony

       
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