A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
From: David Pike
Date: 2020 May 5, 03:52 -0700
Lars Bergman you wrote: Now a new try on the formula that David C asked about. How to find azimuth when knowing latitude, altitude and hour angle?
That’s a very clever formula, which I’m struggling to make sense of at the moment, but I’m sure it’s correct. Could you possibly provide a labelled diagram or explain a bit more about X. Also, there’s still one point that’s troubling me. Ignoring the maths, if you take a fixed length piece of string to represent zenith distance and a globe. If you place one end of the string on the observers meridian at the appropriate latitude and swing it around the earth’s surface, the other end will cut the Sun/body’s meridian at two places, so the body will have two possible azimuths, unless the touch just happens to be tangential, when the angle opposite co-lat will be 90°. One point might be highly unlikely, or impossible to observe, but there will be two points. DaveP