The natural Navigation: The Right Course, Naturally

In this photo, one of the Outward Bound Oman instructors, who I visited recently, is being taught how to use a traditional and beautifully simple navigational instrument called a ‘kamal’.

This instrument is as simple as they get: it works by forming a triangle. If you know the base of a triangle (the fixed length of twine from eye to instrument) and you know the height of the triangle (the number of fingers counted up from the horizon), then you have a fixed angle to the horizon. This is the ancestor of nearly all navigational instruments prior to electronics. (In fact the triangulation used has a lot in common with the way GPS works, but that is another story.)

How does it work in practice?

Here’s the simplest example: the Pole Star (Polaris, North Star) will be the same angle above your horizon as your latitude. At the North Pole…

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Happy Equinox All!

At nine minutes past three this morning, GMT, the sun was overhead the equator.  To celebrate, here are a few things that you may or may not know about the equinox. Only one of them is not true.

The sun will rise due east and set due west for everyone today.

The direction (bearing) of sunrise and sunset changes by more each day at this time of year than at any other time.

On the December side of the equinoxes the sun is always overhead the southern hemisphere, on the June side it is always overhead the northern hemisphere.

Everyone on the planet shares an equal length day and night on the equinoxes.

Satellites that appear stationary and stay over the same spot on the Earth’s surface are called geostationary or geosynchronous and they remain in orbit over the equator. As the sun passes over the equator…

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Another very enjoyable Beginner’s Guide to Natural Navigation course at the Royal Geographical Society yesterday. The diversity of interests and experiences never fails to amaze me; from desert wanderers to cruise ship sailors and even a sailor from a tall ship in the Pacific. Wonderful!

It was a beautiful full moon last night and I got to experiment with a new lens that I have bought. Still a long way to go until I take a photo of the moon that I am happy with, but always learning which is satisfying.

The phase of the moon appears the same all over the world, but the orientation changes depending on your latitude. In other words, a full moon will be full all over the world, but its features may appear upside down from the opposite hemisphere. When high in the sky, crescent moons will appear closer to ‘vertical’ at higher…

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