Common solar alignments
Everyone knows that the sun rises in the east and sets in the west…more or less. But the sun only rises due east and sets due west on the day of the autumn and spring equinox, the midway points between the summer and winter solstices. So what happens at other times?
On the summer solstice (longest day) in northern latitudes sun rises in the north east, peaks at its annual high point and sets in the north west. From that day on it rises and sets slightly more southerly and peaks slightly lower until the winter solstice. At the winter solstice (shortest day) it rises in the south east, peaks at it’s lowest high point and sets in the south west. After the winter solstice it begins to rise and set further north each day until it is the summer solstice once again.
This change in position is most noticeable around the equinoxes when the days change rapidly. It is barely noticeable at the solstices. The word solstice is derived from standstill, which is exactly what the sun’s rise and set positions appear to do at these times.
As well as solstice and equinox alignments, it is possible to find cross quarter day alignments. Cross quarter days occur exactly half way in time between the solstice and equinox (although their bearings are not half way between).
So there are 5 sunrise (and sunset) alignments that occur at 8 points throughout the year as follows;