You would think by now I'd got it.
The sun is highest in the sky at the summer solstice!
Well yes but how, why?
I'm trying to find the words to explain before I commit to html. Here's my attempt so far.
The sun is so obvious, so bright, it drowns out the stars and gives the impression that a rotation of the earth should be measured in relation to the sun.
Each time the earth makes a single rotation the axial tilt causes the angle between the celestial equator and the ecliptic to sweep from -23.4 degrees to + 23.4 degrees and back to -23.4. One rotation of the earth takes 23 hours and 56 minutes, but one rotation in relation to the sun takes 24 hours.
That difference of four minutes causes a cycle of changing declination to be repeated over the year and shows up as the change in solar declination and, in the constellations 'behind' the sun - the four minutes difference between solar and star time means that the sun appears to move through all the constellations along the ecliptic - from Aquarius to Capricorn - in the course of one year.
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