NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
From: Frank Reed
Date: 2013 Feb 16, 15:39 -0800
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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