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A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Summer Solstice PV Sun Obs.
From: Greg Rudzinski
Date: 2014 Jun 21, 12:21 -0700
From: Greg Rudzinski
Date: 2014 Jun 21, 12:21 -0700
Here is a summer solstice morning prime vertical observation of the Sun using an artificial horizon. The sextant was preset to 90° 10' using 2x arc sin{sin d / sin L . There is about an 8 minute window where the azimuth remains close to 90°. The actual observation showed the Sun images slightly seperated and diverging from the preset which indicated that the Sun had just passed prime vertical. No need to figure azimuth for this type of observation :)
The index card shows a Doniol longhand reduction checked by slide rule and phone app.
Greg Rudzinski
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