The first day of summer in the Northern Hemisphere was June 21st which was the longest day of the year. This also marks the first day of winter in the Southern Hemisphere. In order for that to occur, June 21 -22 was the shortest night of the year. The relationship that our planet has with the sun is complex.

There are two solstice periods that occur. June 20 – 21 is one of them and it involves the rays from the sun being on one of the tropical latitude lines. The second period occurs around December 21st and the two solstice periods will be reversed for those hemispheres.

As the Earth is moving around on its axis, there is a line that could be placed right through the middle of it – the North and South Poles. When the axis tilts we are able to enjoy the various seasons that occur throughout the year. The direction of the tilting determines if we will have summer or winter like temperatures during that period of time. It also determines when we have spring and fall.

This tilting explains why areas including the Tropic of Cancer and the Tropic of Capricorn have no seasons. The temperatures remain warm and humid all year long. There are some season changes that occur at the upper latitudes of these tropic areas but they aren’t as profound as what is experienced elsewhere.

During the solstice periods there are some interesting things going on around the world. For example on June 21st there will be a period of 24 hours where it remains light just North of the Arctic Circle. At the same time there will be a period of 24 hours of complete darkness around the Antarctic Circle.

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