**Celestial Navigation. The Ultimate Course**

### Although the prime aim of this book is to teach the practical skills of celestial navigation, it is emphasised that without knowledge, skill is nothing; at the same time, it is recognised that students quickly lose interest if they are expected to plough through reams of theory before they can get down to the business of learning the skills. With this in mind, this book has been uniquely designed to teach the important skills from the outset while ‘tying-in’ the relevant theory as progress is made. There are numerous examples and self-test exercises which enhance the learning process and help to embed the knowledge and skills needed to practise the art of celestial navigation.

The traditional method of celestial navigation involving the use of spherical trigonometry to calculate a vessel’s position is comprehensively taught in this book. At first sight, the term ‘spherical trigonometry’ might seem quite daunting but with the knowledge of just two formulas and with a little practice of the methods explained in this book, it will be found to be quick and easy to apply as well as very accurate. With this method, we make accurate calculations using data taken directly from a vessel’s DR position and so avoid the inaccuracies of sight reduction methods that involve interpolation from tables using data based on an ‘assumed position’.

Although it is a large book (containing 366, letter size pages) it is thoroughly cross-referenced and its layout enables the reader to move from one section to another without having to read it from beginning to end. With regard to the mathematical aspects of the subject, the author has adopted a language style which allows the text to flow smoothly and makes for enjoyable reading which is a departure from the stilted, academic language of many text books.

Note. The terms celestial navigation and astro navigation are generally regarded as synonymous.