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    Re: Sundog
    From: Brad Morris
    Date: 2013 Feb 16, 19:34 -0500

    parhélie

    http://en.glosbe.com/en/fr/sundog

    On Feb 16, 2013 6:45 PM, "Frank Reed" <FrankReed@historicalatlas.com> wrote:

    Bill B, you wrote:
    "Of importance Frank did not specify this is the sundog he saw, but rather the sundog YOU are facing."

    Yes. That was the idea. It was a little puzzle inspired by the photo. This is something that can, in fact, happen. You're out for a walk in the woods near sunset. You see a sundog but can't see the Sun. If you know enough about the Sun's position in the sky, then you can get a pretty decent azimuth, within a degree or so. Another similar case involves determining the Sun's altitude and azimuth when you can see a rainbow, but the Sun itself is not visible for some reason. It's the same idea. A rainbow has a fixed angular relationship with the Sun in the sky. This isn't navigation quality material. It's more about having a quick sense of orientation from some basic knowledge of sky phenomena.

    "To me this means MY sundog could be at any longitude I specify near
    sunset."

    Right. It makes little difference as long as we're talking about observers in the continental US (which I should have specified). The Sun's declination only changes by a few minutes of arc between sunset on the east coast and sunset on the west. Given the single degree precision of the inputs that I specified, and given the rather approximate ability to decide where a sundog begins or ends, that change in declination makes no difference. Even in other longitudes, it would barely matter.

    For Antoine, is there a common name in French for a "sundog"?

    -FER
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