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Scotland Noon Measure
May 4, 2005

Just recently I was browsing and came upon this site The information got me interested and so I did my own investigation. Using an Astronomical program (skychart 111) to give me the precise Azimuth altitude location for the sun relative to my precise coordinates here in Forres. The map reference coordinates are 57° 35' 46" N and 3° 37' 30" W. I took a reading from the astronomical software at 12:31 pm today May 4th 2005, and the results were as follows. The Suns Azimuth was situated at 165.8316 and its altitude was given as +47.8226.

I have a map reading compass which has a lid over it, the compass base is rectangular; so when you open the lid, and place the compass in the sunlight. You can use the edge of the lid shadow to line up with the edge of the rectangular base. This gives you a precise direction for the sun, you then rotate the compass dial to align with the north to north facing needle. Using this technique I obtained a reading at 12.32 pm, this gave an azimuth of approximately 172°. From this I could see that the position of the Sun was about 6.5 to 7 degrees advanced. In other words it was out of position for this time of year/day.

To obtain the Solar altitude I created a shadow on a white piece of paper with an object of a known size/height; I then marked the end of the shadow, and measured the distance. Knowing the height of the instrument and the length of the shadow. I could then place these figures into Turbocad, and get the angle in + degrees for the Solar altitude. The figure that came back was +49.2829°, now remember that the astronomically calculated Solar altitude was supposed to be +47.8226°. The measured +49.2829° places the Sun about 1.5° higher in the sky than it is supposed to be for this time of day. What is also interesting is this, the highest the sun is supposed to reach in the sky for this location and time of year is about +48.5°, Solar zenith would be about 13:13 pm So at 12:32 pm the Sun was about a whole degree higher than it should be at zenith. It will take approx 3 more days for the zenith sun to reach +49.32°, which is only fractions of a degree higher than my 12:32 pm measurement of today.
Forres, Scotland