NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Theoretical Question - Height of Eye from Shore
From: Peter Fogg
Date: 2007 Nov 18, 21:40 +1100
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From: Peter Fogg
Date: 2007 Nov 18, 21:40 +1100
Michael Daly wrote:
Or:
Square root of height of eye x 0.97 (in feet)
Square root of height of eye x 1.76 (in metres)
You can see how close Frank's approximation of square root of height of eye (in feet) is - as close as 0.97 is to 1.00. If you are using whole minutes of arc only, then its the same correction (3 minutes of arc) between 6 and 13 feet of elevation.
A simple version (based on a spherical Earth - reasonable for the
distances you're likely to worry about) is at:
http://en.kayakwiki.org/index.php/Horizon_distance
Or:
Square root of height of eye x 0.97 (in feet)
Square root of height of eye x 1.76 (in metres)
You can see how close Frank's approximation of square root of height of eye (in feet) is - as close as 0.97 is to 1.00. If you are using whole minutes of arc only, then its the same correction (3 minutes of arc) between 6 and 13 feet of elevation.
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To post to this group, send email to NavList@fer3.com
To , send email to NavList-@fer3.com
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