Classes in celestial navigation and related topics

Micrometer sextant Circumpolar stars and Polaris for latitude Dennis DiCicco Ship and horizon A variation on the Equation of Time A Plath sextant Sights around Local Apparent Noon Sights at Beavertail on Conanicut Island

Modern Celestial TWO: Position Fixes & Star Sights

Fall 2020:

This is not your grandparents' celestial navigation! We focus on celestial for the 21st century, applying traditional sextant sights to modern ocean sailing. In Modern Celestial TWO we continue directly on the modern sight analysis from Modern Celestial ONE using streamlined, modern algorithms, and we learn how to find general position fixes from the Sun and also star sights under all conditions. We cross lines of position to get a fix in latitude and longitude during the day with the Sun, during twilight with stars, and even in the middle of the night under the right conditions. And we learn how to manage errors and assess the reliability of a celestial fix.

If you're dreaming about a trans-oceanic voyage or a circum-navigation, in this workshop you'll learn all the techniques to determine latitude and longitude anywhere on Earth using the Sun and the key navigational stars. We'll also discuss celestial navigation options for upcoming ocean races with celestial opportunities including Newport-Bermuda, the Golden Globe Race, and others.

We learn how to adjust celestial lines of position for vessel motion and synchronize Sun and star sights taken at different times for a running fix. We'll also discuss practical tricks for simplifying the navigation process including sights at sunrise and sunset properly adjusted for refraction and other issues.

And we learn the stars. Many navigators give up on the stars and never learn to identify even the brightest stars like Vega, or Arcturus, or Canopus, let alone Rasalhague or Zubengenubi! By the end of this course, you'll know reliable methods and tricks for identifying more than two dozen of the key stars of celestial navigation, enough to sail the globe safely for decades. Valuable as much in coastal navigation as in mid-ocean, a navigator who knows the stars follows a perfect compass all night long.

Pre-requisite: Modern Celestial ONE is strongly recommended.

$149 per person, per workshop

Note for online sessions: You may attend an Atlantic session starting at 12:00 noon Eastern US time, or a Pacific session starting at 6:00 pm Eastern US time (these start times are equivalent to 1700 UT and 2300 UT respectively). Currently Atlantic sessions run for 4.5 hours each day on Saturday and Sunday. Pacific sessions run for 3 hours each day on Monday, Tuesday, Wednesday.

Anyone registered for an online workshop will be invited to attend hour-long sextant practical sessions in Rhode Island and Connecticut scheduled as weather and social distancing permit. These live, in-person sessions are included in your registration for online classes.

Taught by Frank Reed, a gifted teacher and a recent guest expert in celestial navigation on Neil deGrasse Tyson's StarTalk science talk show on The National Geographic Channel.

  • Nine hours in online sessions.
  • Requirements: Basic addition and subtraction, good familiarity with latitude and longitude. Some familiarity with basic algebra, especially positive and negative numbers.
  • Recommended for ages 18 and up, students as young as age 13 welcome.
  • You'll need to purchase the recommended scientific calculator for the class: the "Casio fx-260 Solar" (original or newer "II" model). These are widely available for less than $10 at Walmart, Staples, and other stores. Android users can try my functionally near-identical app: download sc-beta.apk.

    Casio fx260 solar calculator


Jeffrey Rock wrote: 11/9/2020
Lunar Distance and Age of Sail Classes:
Fascinating classes taught by a fascinating and capable instructor.
Lunars class is challenging and fun. Frank presents several different recipes for accomplishing lunars, one of which seems almost easy (kind of). Highly recommended for anyone interested in celestial navigation or nautical navigation history.

Jeffrey Rock
FAA Designed Pilot Examiner
Greg Rudzinski wrote: 11/2/2020
The online class "Lunars: Finding Longitude by Lunar Distance" was a very interesting introduction to the esoteric history of lunars as practiced at sea in the pre chronometer 18th century tall ship era. Practical instruction was also done demonstrating the physical process of observing a lunar with a sextant followed by a how to lunar sight reduction example using a pocket calculator, formulae, and tables. A very rewarding experience.

Greg Rudzinski
Retired Merchant Mariner
SUNY Maritime class of 80
Doug MacPherson wrote: 5/16/2020
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.
Samuel S Lyness wrote: 4/29/2019
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
Captain Richard D. Buchanan wrote: 11/12/2019
I have taken Frank's Modern Celestial Navigation class twice. I am always inspired and I always come away with a few practical techniques and more than a few insights into the history and beauty of celestial navigation. You owe it to yourself to enjoy this class, whether or not you are a mariner.
John Workman wrote: 11/20/2018
I just took one of Franks classes and it was awesome!!

Frank taught an incredible class on celestial navigation that brought me from novice to some solid understanding of sextants, their history and most importantly their use as a aid to seeing the sea...and knowing where you are on this planet!

Hands on, wealth of knowledge, great resources at Mystic Seaport, he really covered a lot of ground! There was a lot of math but unlike in my youth, I was on the edge of my seat to soak up knowledge!! Frank made it relatable and real. The sextant which is such an iconic tool of the sea, was demystified. By the end of class i felt comfortable with it. I had mastered how it worked, how to read it and how to adjust it to insure its accuracy.

I came away with all of the cheat sheets and understandings of equations and concepts that breathe the life into what you capture through your sextant sightings.

I would highly recommend Frank and believe the Mystic Seaport with its planetarium, an ideal setting for my class with him discovering this timeless tool of the sea.

Frank did a great job keeping the class interesting with visual aids, both on screen and out on the seaport grounds. Frank had also noticed i was interested in the Draken. This is the Viking ship which had made its voyage across the Atlantic and up and down the east coast, resting for winter in Mystic as the troops regroup, gathering resources for another ocean voyage. He took extra time to talk about and show with polarized film the concept of the "Viking Sun Stone" which is a suspected navigational aide the Vikings may have used to traverse the globe as they had.

All in all i would highly recommend this class to any and all folks interested in learning about navigation and sextants. Informative and digestible, but most of all useful to the point where i am comfortable with the instrument and have the formulas needed to continuing to set my sights on the horizon!!

I look forward to more classes to learn more from Frank and strengthen my understandings of celestial navigation!

Thank you!!!
Mark Coady wrote: 6/6/2017
I have now done every course I think that has been offered so far at Mystic Seaport taught by Frank Reed in the last two years. I found the courses to all be extremely rewarding.

Several things stand out. The course material is presented in a balanced way, with a well thought mixture of detailed calculation, broken up by historical, factual, and hands-on aspects. This type of teaching is well suited to most, as it provides periods of more intense reasoning with relaxation and humor. Anyone can walk away with new-found knowledge. I also feel that the approach of understanding historical context and a simple practical approach is unique. It has gone a great way toward clearing up a lot of my preconceived ideas and confusions resulting from the many contradictory or esoteric approaches found in various volumes or on the internet.

Very simply, I learned a lot and it went a long way toward clearing up a mess. I was fascinated the whole time. The courses and NavList provide the tools to keep learning even after the course is over. I left able to measure what I see with a more calibrated eye for real world application, and a greater appreciation of human history. I can strongly recommend these classes for the curious, the fascinated, the historian, the hardcore navigator, or the armchair one. There is something in them for all.

I also found the NavList community to be helpful and encouraging as my journey continues. I hope I can undertake even more material in additional courses in the future.

"There is nothing - absolutely nothing - half so much worth doing as simply messing about in boats" (Kenneth Grahame, from the "Wind in the Willows")

Capt. Mark

Dr. Russell D. Sampson wrote: 6/22/2017
I took Frank's 19th Century Celestial Navigation class in April 2013 and really enjoyed it. Not only was the class interesting but my fellow classmates were too; a retired skipper of a ballistic missile sub, the son of the fellow who invented GPS, a teacher, a captain of a Panamax container ship and a fellow who crossed the Atlantic solo - twice!

The class was also a great resource for my teaching and my own research interests such as the visibility of celestial objects in the daytime (Jupiter and Venus) and the effects of astronomical refraction near the horizon. I hope to take more workshops with Frank.

Dr. Russell D. Sampson
Wickware Planetarium
Eastern Connecticut State University
Philip M. Sadler wrote: 6/22/2017
What a joyful and stimulating experience to enroll in Frank Reed's class, Celestial Navigation: 19th Century Methods. Frank is a skillful and engaging teacher, able to draw students into this fascinating subject, whether they be novice or experienced. His depth of knowledge is tremendous. Participants get a real taste of what it was like to be aboard a sailing ship of the day. I learned much to enliven my own teaching and decode 19th century ship's logs. It is a rare experience, indeed, to have so much thoughtfulness, enthusiasm, and fun packed into two days. This is the way to learn!

Philip M. Sadler, Ed.D.
F.W. Wright Senior Lecturer in Celestial Navigation
Harvard University Astronomy Department
Cambridge, MA

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