Longtime sailor releases book on celestial navigation

Most sailors depend on radar for navigating the ocean. 

But David Berson, who has operated vessels on the East End for more than 25 years, uses what he calls “old school navigation” — or celestial navigation, the art of using a sextant to measure the angular height of a celestial object above the horizon — to travel the open seas. 

Mr. Berson, a contributing editor to Ocean Navigator magazine and a former instructor at the New York Hayden Planetarium in Manhattan, spent the past two and a half years writing his new book about navigating by the stars. “Celestial Navigation: A Practical Guide to Knowing Where You Are” will drop Nov. 20 through Seahorse Publishing.

We sat down with Mr. Berson to understand what celestial navigation is and how he first learned about the centuries-old technique.

Q: Can you start by giving me some background on your book and what celestial navigation is? 

A: When I started sailing in the early 1970s, going off-shore, crossing the Atlantic Ocean — there was no GPS. Sailors traditionally found their way by using the sun, the stars and the moon, a system that had been evolved since the mid-1700s, when Sir Isaac Newton developed the concept of the sextant … When I started coming up as a younger man, sailing on a large ship … we would take boats like the Harvey Gamage and take passengers from Greenport or parts of Connecticut down to Bermuda, and then down to St. Thomas. I was told that if I learned celestial navigation, I would probably always be able to have a paid job on a boat. I loved being out at sea. I loved the camaraderie, I loved the fear, the thrill — I just loved it all. I learned the subject through teaching. So, the more I taught, the more I understood. The more I understood, the clearer I was able to make the subject, because it’s shrouded in confusion by math, and numbers. People who made it wanted to make it more difficult than it seems to weed out the people who aren’t devoted. In actuality, celestial navigation is fairly simple, but it’s been shrouded in this fog of mystery. So, I became adept at it. I’m not perfect, I still make math mistakes, I still count on my fingers. But I’m persistent, and I know how to explain it very well. 

Q: Why did you choose to learn about this subject? 

A: It was good for me to learn it. It put me in touch with things that I hadn’t really thought about before — the way the universe works, the mechanisms of everything. Everything in the world is connected to looking up at the sky at night, or during the day. That’s the natural world we live in. People for thousands of years — it started with the Babylonians — were always trying to figure out the connection between the orderliness of the stars and the sun, with the planting cycles and the rise and fall of the Nile River. So, navigation by the stars is as old as mankind. People have always wandered away from their homeland to go hunting and gathering food, and the stars led them back home.

Q: When did you first learn about celestial navigation? Who was teaching you? 

A: When I was 24, I got a job going trans-Atlantic on a big sailing ship and it was very exciting for me. We had a navigator aboard and everything was done via celestial navigation. I was absolutely fascinated by the process, but every time I asked the navigator a question, he was either purposefully obfuscating or he didn’t know how to communicate the information … When I got back from traveling, I immediately signed up for a program at New York Hayden Planetarium for navigation that was given by a great teacher, Fred Hess. I’ve taken a couple classes with him, I practiced, I learned at sea, from the books and, later in my life, when Hess retired, I took his position at the Hayden Planetarium. I’ve never did it as well as him, but it completed a circle in my life.

Q: You’re definitely a pro — but did you have to conduct any further research on celestial navigation before publishing your book?

A: I wrote at least five drafts of this book. … The last three drafts I did, I completed as much transparency as I could so I addressed the readers in a way that did not make me smarter than them. I simplified it for them. I admitted all of that. As a matter of fact, I have a friend who’s a friend of The Amistad, who came into Greenport Village this summer. She has younger sailors aboard, and she told me she was reading my book to them and they understood it completely. Which, to me, is a major accomplishment. In terms of your initial question — I must have 150 books on navigation on my bookshelf because I’m a voracious reader and I’m always willing to see how others explain things. I acknowledge in the book that there are other books you can go to that call for a more detailed analysis of what I’m saying about celestial navigation. Many of these books are designed for the professionals, which mine is not. My book is designed for the curious person who wants to understand a methodology. I wanted to make it accessible.

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Photo caption: Navigator David Berson discusses celestial navigation with a sextant in hand last Saturday at Floyd Memorial Library. His book will be released Nov. 20. (Poppy Johnson photo)