The Northumberland Public Library will repeat Celestial Navigation from 6 to 8 p.m. for six consecutive Fridays, 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 Mykonos Island Greece and back.
“Celestial navigation is making a comeback,” said Schmalz. “After 15 years out of its syllabus, the U.S. 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 580-5051, or firstname.lastname@example.org, or register at the first class.