A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
From: Ed Popko
Date: 2018 Nov 15, 03:03 -0800
Why did navigators abandon sexagesimal angle notation and adopt degree-minute-tenths of minute? For example: 30° 45' 30" vs. 30°30.5'
Was this a convenience for doing arithmatic? It is definately easier to add and subtract angles expressed in degree-minute-tenths of minutes. Perhaps less error prone too.
Was the change brought about by some major event like World War II. There must have been a time when almanacs, reduction tables, or math reference tables (trigonometry, logarithms ...) switched over.
Older sextant verniers often use sexagesimal too but all newer ones use minutes and tenths of minutes.