Category Archives: Uncategorized

Meridian Passage Methods.  Short Method.  In the case of stationary or very slow moving vessels, it is acceptable to use the Meridian Passage Short Method which involves calculating the time of meridian passage at the current DR position. Long Method.  … Continue reading →

See the latest article: Venus Evening Star or Morning Star? Although this website aims to promote the Astro Navigation Demystified series of books, it is hoped that it will also provide a useful resource for navigators, scholars and students of the subject. … Continue reading →

Unit 5 – Demonstration of a 3 point fix. Aim.  We saw in unit 4 how a position line is obtained from a single intercept; the aim of this demonstration is to establish a 3 point fix based on the … Continue reading →

Point Z represents the zenith of the observer’s position.  Point X represents the position of the celestial body and this point, if projected onto the Earth’s surface, would correspond to the Geographical position of the body. P and P1 are … Continue reading →

First Point of Aries.  In astronomy, we need a celestial coordinate system for fixing the positions of all celestial bodies in the celestial sphere.  To this end, we express a celestial body’s position in the celestial sphere in relation to … Continue reading →

This post continues the series Finding Stars and Constellations. Lyra, Cygnus and Aquila – The Summer Triangle. The diagram below shows the constellations Lyra, Cygnus and Aquila. If we follow the reference line ‘the Pointers’ from Ursa Major to Polaris, … Continue reading →