HangDial

A very easy to use universal sundial/sextant -equivalent type thing to get the angular height of the sun above the horizontal.

Purpose: To determine the elevation i.e. altitude of the sun (full range, i.e. 0 to 90 degrees), when on land and when it's not too windy. Comes with a chart and tables that help you work out your latitude and also the current time, pretty much nearly anywhere/anytime in the world you are. For similar but for stars/Moon at night (or, if you want vertical angles to landscape features) use the StarSquare or StarRings instead.

Caveat: This thing and the associated PDFs are not intended for life-critical or indeed any applications other than educational only! Use for navigation etc. at your own risk!

Accuracy: Perhaps around 0.25 degrees or so: not as accurate as a sextant and an artificial horizon, but unlike that setup it will give you an elevation even when the sun is high in the sky. The half-size version is perhaps around 0.5 degrees.


Usefulness:

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