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A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Celestial Navigation Noon Sight Example - Video
From: Bill B
Date: 2016 Jul 26, 17:51 -0400
From: Bill B
Date: 2016 Jul 26, 17:51 -0400
On 7/26/2016 3:43 PM, Graham England wrote: > Last year I studied how to do a Noon Sight and created a 45 Min video. > If you have the time I would like someone who knows the subject to > review the video. (I started this before Frank's review and had to take a break.) I started to view and download the video so as to digest it a bit at a time. Roughly 00:2:20 in there is misinformation (perhaps corrected later?). That being the Sun will be in the same place at the same universal time day after day, and it will reach it's highest point in Greenwich at 12:00:00. None of the above is true except in special cases. 1. Due to changes in declination the sun will be higher or lower from day to day 2. Due to the equation of time (EQ) the moment the Sun reaches it maximum elevation can vary by approximately plus/minus 15 minutes over a period of months. The best way for a student to visual see the affects of position (elevation and EQ time) is the analemma, the figure 8 diagram often seen on globes and sun dials. If the rest of the video follows suit [I do trust Frank's judgement], I would echo Frank's suggestion and remove the video. Without flaming, you need to study the motion of celestial bodies in general and celestial navigation specifically. If you do not understand what you are presenting, please do not attempt to instruct others.