Category Archives: gps

In Defence of Mer Pas

The noon sight for latitude is a method of calculating latitude from the altitude of the sun at the instant it crosses your meridian and for this reason, the method is also known as ‘Meridian Passage’ or ‘Mer. Pas’.  I … Continue reading

Posted in astro navigation, astronomy, celestial navigation, gps, navigation | Tagged , , ,

Why Astro?

In a recent article the discussion centred on our over-reliance on GPS for navigation at sea and the need for back-up systems.  The conclusion drawn was that we already have a back-up system, one that has been tried and tested … Continue reading

Posted in astro navigation, celestial navigation, electronic navigation systems, global positioning system, gps, Marine Navigation, navigation | Tagged , , ,

What’s The Point of Astro Navigation When We Have The GPS?

Imagine that you are driving through Birmingham when, suddenly, your ‘Sat Nav’ starts to tell you that you are in Manchester.  In such a situation, you would quickly realise that the GPS had gone haywire; however, if you were in … Continue reading

Posted in astro navigation, Astro Navigation Topics, astronomy, celestial navigation, coronal mass ejections, electronic navigation systems, gps | Tagged , , , ,