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                                                      CELESTIAL NAVIGATION CLASS    2021

                                                                      "We are drowning in information but starved for knowledge."
                                                                                                                                        John Naisbitt

                                                                                               April 1, 8, 15, 22,  2021
                                                                                                       7:00 - 9:00 PM


There is not a more affordable, more information-packed course on Celestial Navigation anywhere, east or west coast included. This is a great opportunity to learn an important navigational skill ancient mariners have refined over the centuries, and is still viable today.


Our well-qualified instructor, Douglas Hendricks, is a USCG-licensed 100-ton Master who has been sailing for more than thirty years, crossing the Atlantic, Pacific and Indian Oceans as well as many different long ocean passages, using sextant-only navigation.  He has been teaching Celestial Navigation for Bonneville Sailing since 2008.


The class is open to anyone, anywhere in the world who has an internet connection. Different options are available to fit the needs of all students, whether they be totally new to the subject, or sailors who have already know something about celestial navigation but who need to fill in some gaps in their knowledge.


Unique Format of the Bonneville Sailing Celestial Navigation Classes          


With our “Live-Class Option” you’ll join with other students in a live, Zoom-based, instructor-led class. There are four, two-hour class sessions, during which you can ask questions and get immediate feedback, just the same as if we are all sitting together in the same room, even though we might be on opposite sides of the world. After completing the first two class sessions, students will be able to take sextant sightings of stars, planets, sun, and moon and then enter those measurements into a smartphone app in order to determine their latitude and longitude. The agenda for the last two class sessions is to set the smartphone aside and learn how to convert the sextant readings into a lat/lon position ourselves, a process called “sight reduction”. There are two ways we can do these sight reductions: one way is to use books of tables (H.O. 229 or H.O 249), and the other way is to use a simple, non-programmable calculator. The preferences of the students in the class (based on a pre-class survey) will determine which of those two ways we’ll learn. There’s not enough time in just four short class sessions to learn both sight reduction methods, so if a person wants to learn both methods then after the fourth class session is over they can take advantage of the “Consulting Option”, described below, to learn whichever of the two sight reduction methods the majority of the people in the class voted to skip.

With our “Recorded-Class Option”, you can watch video recordings of class sessions that were held previously. The fee for this class includes some one-on-one consulting time with the instructor (via phone or email) for people who might have questions after watching the recordings.

Our “Consulting Option” is for people who’ve studied enough on their own to where they don’t feel the need for taking the full class, but instead just need a little Q and A time with an experienced celestial navigator. It also is here for people who want to learn both of the sight reduction methods described above.

Topics Covered During The Class:
• Review of earth-based navigation methods including: reading nautical charts, doing ded reckoning, correcting for magnetic variation, etc.
• How to identify the navigational stars (and planets) in the night sky
• How to plan your star shots in order to get the highest accuracy in your final results
• How to use a sextant to measure star altitudes (or the sun, moon, or planets)
• How to enter the sextant measurements into a smartphone app to determine your lat/lon position without needing to use any reference books at all... no nautical almanac and no sight reduction tables.
• How to use a nautical almanac to calculate and apply correction factors that need to be made to your sextant readings (refraction, dip, parallax, etc) without using the smartphone.
• How to use a nautical almanac to know the geographic position of the navigational stars (and the sun, moon, and planets) at any given time without using the smartphone.
• How to determine your lat/lon position by doing a noon-time sun shot, using the nautical almanac as an aide.
• How to determine your lat/lon position by doing a noon-time sun shot, using only an analema chart as an aide (without needing the nautical almanac).

• How to determine your latitude by doing a measurement of Polaris and applying necessary correction factors (since Polaris is not exactly aligned with the Earth’s axis).
• Emergency Navigation - How to measure star altitudes with reasonable accuracy even if you lose or break your sextant.
• St. Hilaire’s Method of getting a position fix. How it is that, after using one of the two sight reduction methods described below, you can then plot lines of position on a nautical chart or an open-ocean plotting sheet and then calculate your lat/lon position.

• Sumner’s Method of getting a position fix. An alternate method of calculating our position that is useful in certain circumstances.

 And one of the following two sight reduction methods, depending on the preference of the students as determined in a pre-class survey:
(1) How to enter the sextant measurements into a simple, non-programmable calculator to determine your lat/lon position, using a nautical almanac to know the geographic position of the star (or sun or moon or planet) but not using any sight reduction tables.
. . . or . . .

(2) How to use a book of sight reduction tables (either H.O. 229 or H.O.249) to determine your lat/lon position, without the need for any electronic aides at all, not even a simple calculator.
If a student wants to learn both sight reduction methods then the second one can be done via the “Consulting option”.

Fee for the “Live Class Option”: $250

Fee for the “Recorded Class Option”: $200
Both course fees above include a workbook including detailed handouts, star charts and solved example problems.Course fee does not include the textbook, which is "Celestial Navigation in the GPS Age" by John Karl, and which may be obtained from or

Fee for the “Consulting Option”: $75 per hour of instructor time

Contact Louise at 801.636.5204 to register.


Comments From Previous Students:

"I have taught navigation for many years and have taken other celestial navigation courses. This is by far the best and most thorough course I have ever taken." Emery

"The course was well done. Instructor was very knowledgeable and well prepared. This course was challenging, but instructor made it manageable and fun!" Dave

"This was a great class with a very knowledgeable instructor. I thoroughly enjoyed it." John

"Excellent teacher, challenging and informative. Left me wanting to learn more." Marylou


Contact Us
    •   (801) 636.5204
    •  Utah Lake State Park
       4440 West Center St.
       Provo, Utah 84601
        •  M-Sat: 8am - 9pm