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    Re: Sun altitude limits for natural horizon?
    From: Ron Jones
    Date: 2016 Feb 20, 15:43 -0800

    As the year was not given it would be difficult to determine if the moon was up; however Bowditch warns not us use a moon lit horizon as a "false horizons may appear below the Moon because the Moon illuminates the water below it." See extract from Bowditch below

    Ron

    2002 Edition of Bowditch, page 263, Paragraph 1605. Sextant Moon Sights
    "When observing the Moon, follow the same procedure as for the Sun. Because of the phases of the Moon, the upper limb of the Moon is observed more often than that of the Sun. When the terminator (the line between light and dark areas) is nearly vertical, be careful in selecting the limb to shoot. Sights of the Moon are best made during either daylight hours or that part of twilight in which the Moon is least luminous. At night, false horizons may appear below the Moon because the Moon illuminates the water below it."

       
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