Navigation by the Sun

The sun can be used to navigate – get a rough feeling of North. It’s approximate but potentially life saving.

Assumptions which affect accuracy.

  • Sunrise is West, at 6am, Sunset is East at 6pm – a 12 hour movement. Far away from the equator (close to the arctic circle), this 12 hour figure can become significantly incorrect.
  • In spring, many nations shift their clocks forwards an hour.
  • Midday is assumed to be the solar maximum its highest point – North

With this true, a watch can be used to navigate. 6am to 6 pm is a complete rotation of your watch (360degs), but for the sun, it travels from West to East – half a rotation (180degs). We need to halve things.

Here’s how it works. Point the hour hand to sun, South is halfway between the hour hand and midday on your watch. Simple. Examples:

  • Imagine it’s 9am and you want to know which way is North. Rotate your watch so that your hour hand points to the sun. South is half-way between your hour hand and the 12 position.
  • Imagine its sunrise and 6am. At sunset (as below), the sun is West. No watch required – but the technique still works…

NavBySun1

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