I recently took online versions of Frank Reed's "Celestial Navigation in the Age of Sail", and "Lunars - Finding Longitude by Lunar Distances". I couldn't have been more happy with them. Having originally learned post WWII celestial methods as an officer in the United States Navy, and taken it up as a hobby, I was quite familiar with that era's procedures. However, I was intrigued by how they managed prior to then. Frank's two classes filled that void. His vast knowledge of the subject, both the technical aspects of the work as well as the historical significance were perfectly balanced. These are classes that can be thoroughly enjoyed by both the novice as well as the well versed practitioner. Recipe's for doing the work, the science behind those recipes, and actual voyages by the sailors that practiced the art were all presented with wonderful clarity. If "time sights", "cleared lunar distances" or "apparent time" have ever roused an interest, you owe it to yourself to take one of Frank's classes.
Doug MacPherson
Lieutenant, USN sep.
Lunars and Longitude
Winter / Spring 2026:
Learn the art of Lunars, the famous celestial navigation method of finding longitude by observing the Moon in this intermediate-level workshop. Taught by Frank Reed, the world's leading expert on the history, science, math and practice of lunars. We cover practical application of the method as well as its extraordinary history, including primary-source evidence in the logbooks of the museum's collections. We will follow an extraordinary voyage in the 19th century, a Boston trading ship on a quest for coffee, sailing to India and home, all thanks to Lunars. And we'll follow William Bligh and the "Bounty" to Tahiti and the famous mutiny that followed, relying on the Moon for their successful navigation.
Lunars were widely used at sea in the early 19th century in the era before chronometers became common. Lunars made global navigation possible. Observing with a fine sextant, navigators used the Moon as a great natural clock in the sky. From James Cook and Nathaniel Bowditch to Joshua Slocum, lunars were a challenge that proved a navigator's skill.
Participants in this workshop will learn the fine details of adjusting a sextant properly for shooting lunars, tricks for taking accurate sights today, and easy methods for working with these infamously difficult observations both by modern and historical means. We'll also talk about some of the interesting mathematics and astronomical discoveries that made lunars possible. For a modern celestial navigator or navigation enthusiast, there is no better test of your sextant and observing skills. Weather permitting, we will have opportunities to take actual lunar observations.
All workshops: $ 149 per person, per workshopCreated and taught by Frank Reed, celestial navigation and astronomy consultant on the team that found Shackleton's "Endurance" in 2022. Also a recent guest expert in celestial navigation on Neil deGrasse Tyson's StarTalk on The National Geographic Channel.
- Nine hours of class sessions.
- Requirements: an introductory course or equivalent in the the use of a sextant and other basic concepts of celestial navigation.
- Previous attendance in our Celestial Navigation in the Age of Sail is recommended but not required.
- Good math skills and some familiarity with trigonometry are recommended.
If you're registered for an online workshop, you're invited to attend hour-long sextant practical sessions in Rhode Island and Connecticut scheduled as weather and other factors permit. These live, in-person sessions are included in your registration for online classes.
Comments:
Doug MacPherson wrote: 23👍
Samuel S Lyness wrote: 8👍
Frank, a wonderful course in Lunars. I learned a lot. I admire your teaching skills and your astounding fund of knowledge. I would wish to emulate your style of instruction. Best regards, hope to sign up for your course in Cel. Nav. in Age of Sailing.
Sam Lyness
Sam Lyness
Lucinda Fleeson wrote: 26👍
"Celestial Navigation in the Age of Sail" was exactly what I was looking for to familiarize myself with historical marine navigation. Frank is an engaging instructor who weaved the story of a 19th century whaling voyage into hands-on practical calculations. He started by unveiling an incomprehensible historical document filled with numbers and promised that by the end of the course we could decode the figures. He's developed a step-by-step teaching method that is a marvel to watch and experience.
I must admit I dreaded two, back-to-back, 5-hour days, but the time sailed by. (Sorry can't resist.) Thank you.
He also included some 17th century data that I needed. I'm neither a mathematician nor a sailer, but a journalist and author.
I must admit I dreaded two, back-to-back, 5-hour days, but the time sailed by. (Sorry can't resist.) Thank you.
He also included some 17th century data that I needed. I'm neither a mathematician nor a sailer, but a journalist and author.
