The axis of the Earth is tilted with respect to the plane of its orbit around the Sun. This is what gives us the seasons, as the north and south hemispheres point towards then away, then towards again, over and over in an annual traverse of the orbit. When the north pole of the rotational axis points towards the sun, it makes for longer days in the northern hemisphere; when it’s pointing away from the sun, it makes for shorter days. And the complementary opposite is true for the southern hemisphere.

Because of this, there are four cardinal points of the year … The Solstices and the Equinoxes. The Solstices are the times when the day or night is longest … for the north, the Summer Solstice is the longest day and the Winter Solstice the shortest. The opposite is true for the south. The Equinoxes are the days when the rotational axis lies in a plane tangent to the orbit around the Sun … all points on earth obtain an equal length day and night on those two days, Spring (Vernal) and Fall (Autumnal) Equinoxes. 

The other effect of this tilted axis is that the length of the day varies not only based on the position of the Earth in its orbit around the Sun but also on what latitude you are measuring daylight hours at. At the equator, the length of days is always the same. As you move towards either pole, north or south, the length of the day between Equinox and Solstices varies more and more. When you are beyond a certain latitude, there are periods of the year at both poles when the sun never sets and also when the sun never rises. 

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I went on my walk a little earlier than recently today, around 5:20am I was out watching the sunrise through the trees. It was a cloudy, soft morning light, the air heavy with water as the sun began to warm things up through the clouds. And it struck me that we’re now well past the mid-point of Summer and moving quickly towards the Fall Equinox: the sunrise was much later than the last time I walked at this hour. 

I stopped for my coffee and was sitting outside thinking of this evening’s workshop. A little stage fright, a little tremulous at the thought of standing in front of a group of people to teach. One of the baristas at the coffee shop came outside and was setting up the umbrellas for shade, said hello.

“Falling towards the equinox again,” I said, coming half out of my reverie. 

“Huh?”

“You know, Summer is beginning to end, the north pole will soon turn away from the Sun and we’ll get into Fall then Winter …?” 

“What?”

I shook myself fully awake. And proceeded from there with a brief explanation about what causes the seasons, and the solstices, and the equinoxes. Joe shook his head … 

“Wow, I never thought of that before. That’s amazing. Thanks for telling me that! now I have something to think about!” And went on with his affairs. 

I feel good about the workshop now. Still perspiring however. 
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