Equations for Sundial

Astronomical Computing

Written by Toshimi Taki
March 8, 2008

Equations necessary to make planar sundials are derived. You can choose any orientation for the plane of a sundial.

Download Document Click here to download "Equations for Planar Sundials" (326KB) in pdf file.

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Example of Calculation -- Vertical Sundial for Latitude = 35-degree

Example of Calculation -- Horizontal Sundial for Latitude = 35-degree

Example of Calculation -- Vertical Sundial of Trinita dei Monti (Latitude: 41.9-degree)