Trans-Atlantic voyage teaches celestial skills

The Ocean Navigator School of Seamanship once again will offer its celestial navigation course on a trans-Atlantic voyage aboard the sailing ship Royal Clipper. The crossing, which departs Barbados April 16 and arrives in Malaga, Spain, on or about May 2, will be taught by veteran instructor John Carlisle. (Students also can stay aboard for the next leg to the port of Rome.)

“I’m looking forward to the next crossing aboard RC,” Carlisle said. “Last time when I asked my students why they wanted the course, they all said in so many words that once and for all they want to crack the code of celestial navigation, really understand what is happening and how it works. Not just using the form but understanding the theory. So, that’s what I do. I show them the geometry of why we can use arc degrees in the sky and on earth and great circles to render a position on earth based on altitude of a body. This is what curious people want to know.”

Carlisle said he teaches theory in whatever way gets the point across in the clearest way: “I have created several unique teaching tools for these lessons. For example, I had a glass blower make a 6-inch orb for me that I use as the celestial sphere; with magic markers we can draw coordinates on the glass. This helps students see how celestial coordinates work with terrestrial coordinates to form the navigational triangle and other coordinate systems. Illustrating the horizon system requires another orb that can actually be opened and a local horizon placed inside the orb; this allows the student to solve the mystery of why stars appear where they do.”

The School of Seamanship also offers a shore-based celestial class (May 13-14 in Marion, Mass.), taught by Ocean Navigator Editor Tim Queeney.

Visit for more information on both the seminar and voyage.

By Ocean Navigator