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Alan

Nominally correct on the 15d/hour movement.  The direction of the body
from you--azimuth--is dependent on the body's altitude (declination and
latitude).

Thikn of it this way. Around LAN the Sun's movement is almost
horizontal.  At sunset it is almost vertical. Therefore the azimuth
changes very quickly around LAN, and slowly around sunset.

Hope that helps.

Bill B



On 7/17/2012 11:36 PM, Alan S wrote:
> As I understand, the sun moves around the earth at the rate of 15
> degrees per hour, actually it's the earth that moves around the sun, but
> the rate of movement, 15 D/hr is the same. Therefore, regarding sextant
> shots separated by 5 hrs 26 min 17 sec, the angles between LOP's should
> be close to 82.5 Degrees.
>
> I shot the sun twice today, both shots from positions within a few feet
> of each other. First shot at 10:04:56. Second shot at 15:31:13, time
> between shots being 5 Hrs 26 Min 17 Sec. The difference in times should
> have given a spread of approximately 82.5 Degrees between LOP's.
>
> I reduced the sights and plotted them, getting a difference between KP
> (GPS coordinates) and calculated fix of less than 2 NM. Measuring, with
> a protractor, the angle between LOP's, I got 55 or 56 Degrees, instead
> of something closer to 82.5 Dergrees, which I think I should have gotten.
>
> Does some dumb error, or grevious misunderstanding my part jump out at
> anyone, or is the angle I measured about what it should be, letting the
> bit about 15 Degrees/hr slide? Any clarification would be appreciated,
> Thanks.
>
> Alan
>

   

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