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Subject: Re: Winter Sextant Sight Accuracy?
From: Jared Sherman (jared.sherman@XXX.XXX)
Date: Thu Jan 10 2002 - 22:27:57 EST
<A change of 14 degrees Celsius in the temperature of the air
changes the refraction by only 0.2 minutes of arc. [George Huxtable]>
And those 14°C amount to 2/10 mile of difference in position from a sight reduction here, from the sample numbers I just ran at Ho 11°30' and 0°C /vs/ 14°C but a difference of 4/10th mile when Ho is down to 5°30'.
So the temperature difference alone can be .2-.4 mile if not factored correctly under winter conditions at 43N on a late afternoon.
But not to digress...the basic question was and still is, what kind of position accuracy is anyone else getting with winter sextant sights at lattitudes above 40° ?
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