Celestial Navigation Course Returns


Back by popular demand, the Northumberland Public Library is offering Celestial Navigation for six consecutive Fridays from 6 p.m. to 8 p.m., starting January 13.

Instructor Jim Schmalz completed the American Sailing Association’s course in Celestial Navigation, ASA107, in 2005, in preparation for a 2006 family sailing trip from Barcelona Spain to Mikonos Island Greece and back.

“Celestial Navigation is making a comeback,” said Schmalz. “After fifteen years out of its syllabus, the US Naval Academy at Annapolis re-instituted instructions in Celestial in September 2015, as fears of possible jamming of GPS signals became more realistic.”

Schmalz will present the Marcq Saint Hilaire, or Intercept, Method, which uses a sextant, an accurate wristwatch, a 2017 Nautical Almanac, a book of solutions called Sight Reduction Tables, the usual plotting implements—dividers and parallel rule. Students will not be required to own a sextant for the class, but those who do buy one will need a little practice to determine a vessel’s position out of sight of land.

High school-age students may want to take this course as it uses astronomy, physics and math. Schmalz will cover techniques for obtaining observations of the sun, the moon, the four naked-eye planets, and the 30 bright stars used for Celestial Navigation in the Northern Hemisphere using one. The class will include field time for demonstration and practice.

In addition to the Intercept Method, the course will include: Obtaining latitude from noon observations of the sun, and from dawn and dusk observations of Polaris, the North Star; maintaining a DR Plot; how to plan a dawn or dusk observation session; how to obtain running fixes from a single body; and the astronomical background required to better understand the discipline.

The course relies on elementary-school math and costs $5, to cover initial supplies and refreshments. Prospective students may pre-register at by calling the library at 580-5051 or email: library@nplva.org. You may also register the day the class starts. Call Jim Schmalz at 804-724-9180 with questions or for additional information.


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