NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
From: Wendel Brunner
Date: 2025 Apr 21, 16:06 -0700
Attached below is an update of a simple method to calculate the GHA and declination of the Sun using two parameters specific to the year. We have included values of the parameters for the years 2025 through 2040. These calculations are quite practical using an inexpensive scientific calculator- less than $10 on Amazon - and are more than accurate enough for small boat navigation. Such a calculator also makes quick work of the formulas for solving the Navigational Triangle, so this approach can replace annual Nautical Almanacs and volumes of tables for working up Sun lines.
I calculated these parameters to update this method to the 21st Century. In addition to using a scientific calculator, this algorithm is easy to enter into a programmable calculator. In 1992 I programmed a small Radio Shack calculator with limited memory with this and several other useful navigational algorithms, and used it to navigate a sailboat to Hawaii without cracking a book or marking a plotting sheet.
Wendel Brunner
