Join our mailing list

Help me choose!

Celestial navigation course

Celestial Navigation Course

It is magical to be able to navigate a yacht using just the sun, moon, planets, and stars.  chart a path with the aid of a sextant is an essential navigating skill. In this intensive two day course, an expert instructor will help you get to grips with celestial navigation. There is no complex mathematics, and anyone with a basic understanding of coastal navigation can attend. By the end of the course you’ll have learnt how to plot a position from observing the sun and will be perfectly places to develop this knowledge into using the planets, moon or stars.

Celestial Navigation


No prior knowledge required

Course overview

This is a theory course that focuses on the sight reduction: traditionally the hardest part of celestial navigation and the area that everyone struggles with. We will give detailed, plain English instruction from first principles – an approach that clearly produces the best results. You will also be taught how to tune and use a sextant and to plot your position on a chart. When you finish the two day course, you should be able to find your position at sea.

Who is this course for?

Anyone can join this course. No prior knowledge of celestial navigation is required. We do suggest you have done some chart work before so you understand Latitude and Longitude and can plot your position on a chart. So whether you are a complete beginner in celestial navigation or already have your Yachtmaster Ocean but need to understand the theory much better, this course is for you.

You do not need to bring any equipment or own a sextant

RYA Yachtmaster Ocean

If you wish to achieve your Yachtmaster Ocean qualification, you will need to have taken three sun sights, complete a qualifying ocean passage and pass an exam. You do NOT need to have taken a 5 day Yachtmaster Ocean theory course to take the exam. Indeed, we believe you are far better to take this two day course, then join one of our ocean passages as a watch leader, where you will receive another day of training in passage planning and two weeks top class practical tuition on a yacht at sea. Whatever anyone tells you, you cannot learn to cross an ocean while sitting at a desk. Trust us! Having completed your ocean passage with us, so long as you have met the required standard you will be more than ready to sit your Ocean exam.


0900 until approximately 1700.

What’s Included:

All course materials, morning and afternoon tea.

Teaching locations:

Rubicon 3 training centre
Unit 2, Haslar Marina
PO12 1NU
United Kingdom
(Free parking available. Nearest train station Portsmouth harbour)

Dorset Wharf Community Hall
158 Rainville Road, Hammersmith, London
W6 9HN
United Kingdom

What’s Included:

All course materials, morning and afternoon tea.

Match this course with:

We also run courses in marine diesel, passage making navigation, and boat electrical.


Essential mathematics (not hard!)

Celestial navigation explained in 15 minutes

Hour Angle explained

Greenwich Hour Angle (GHA)

Local Hour Angle (LHA)

Circle of Equal Altitude

Nautical Almanac

Sight Reduction Tables

Using a sextant


Measuring altitude


Planets, stars, other celestial bodies