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Celestial Navigation

Celestial Navigation - the book

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Mark Breach

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Astrogeodetic Levelling - PhD Thesis

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Celestial Navigation

     The resource site for “Celestial Navigation when your GPS fails! by Mark Breach     


 The Book  


"Celestial Navigation when your GPS fails!" contains everything you need apart from the sextant and a watch. A calculator is handy but not essential. There is complete instruction on how to use a sextant, instruction on making astronomical observations and how to do the calculations with or without the forms. All tables and the forms needed to make the calculations are available. You do not need any further almanacs or tables for the next ten years!

The text describes the celestial framework in which we must operate, with particular reference to the way that the Sun, Moon stars and planets appear and the principles of astronomical navigation.

The sextant is described along with its errors and the necessary corrections that need to be applied. Reductions of observations for dip, refraction, semi-diameter of bodies and parallax are covered. With the theory well established, the practicalities of position finding are described in detail.

There is a chapter on the origins of some of the formulae used for those who want a deeper understanding of the mathematics involved but this may be omitted by those who prefer to focus more on the practice of position finding. The main text concludes with a detailed worked example and blank forms for your own observations of celestial bodies and the calculation of position.

All the tables that you will need are included. All the other tables that you might need depending on when and where you are going are on this website.

Click here to see 25 sample pages in .pdf format, including the contents and index pages, the whole of Chapter 1, the first page of all the other chapters and some tables. This is a 2.5MB file so, depending upon your connection, may take some time to load.

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