The sun rises in the east and sets in the west, right? Not reallt. The sun rises in the exact east and sets in the exact west only two days a year.
Serious sunset observers will notice that in the summer the Sun sets in the northwest and in the winter the Sun sets in the southwest.
You will remember that the ecliptic is the path of the sun,moon,and planets across the Celestial Sphere. You will also remember from your science book that the earth’s axis is tilted 23 1/2 degrees . That means the planes of the equator and the ecliptic are inclined to each other by about 23 1/2 degrees. This is why we have seasons. The tilt of the earth’s axis causes the Sun’s path through the Celestial Sphere to be tilted 23.5 degrees to the celestial equator.
December 21 the sun is at its southernmost point in its travels along the ecliptic. The results of this? The south pole has
the Midnight Sun. The North pole has almost twenty-four hours of darkness. This is the winter solstice,the shortest day of the year and the first day of winter. On this day the sun is as far south of the ecliptic as it will ever get. If you can tear yourself away from Christmas cookies long enough to go to see the sun set,you will see that it is setting in the southwest. This is as far south in the sky as the sun gets.
If you continue to watch from December 22 on,you will see that the sun is setting a little farther north every evening. This continues until June 22. On June 22,the north pole enjoys the Midnight Sun and south pole has almost twenty-four hours of darkness. The sun is as far north of the ecliptic as it will ever get. On this evening you will see the sun setting north west,as far north as it will go in the sky. This is the summer solstice and the longest day of the year. From June 22 on the sun will set a little further south every night.
About halfway between the winter and summer solstice,the Sun crosses the celestial equator and enters the northern hemisphere. That happens on March 21 and is called the vernal equinox,the first day of spring. The result? The day is exactly twelve hours and the night is exactly twelve hours.
The autumnal equinox happens halfway between the summer solstice and the winter solstice on September 23. The sun crosses the celestial equator on its way south. Again the day and night are equal in length. This is the first day of autumn.
The more I know about how these things work,the more I am in awe of Jesus Christ,the Creator of these things. This increases my pleasure in them. These facts make sunsets more fun for me. I hope it does for you. too. Most of all,I hope it turns your thoughts to the Creator.
The winter solstice arrives at 12:11 p.m. (EST) on Dec. 21,marking the shortest day of the year. On that day the United States will get just nine hours and 32 minutes of daylight.
“Up until winter solstice,the sun is moving southward from day to day. As it approaches solstice its southward march slows down,” says Benjamin Burress,an astronomer at the Chabot Space & Science Center in Oakland.
At the solstice the sun stops going south and pauses,motionless. “Then after solstice,it is again moving northward in the sky each day,” he says. Solstice means “stationary sun.”
The solstice occurs because the Earth is tipped on its axis 23.5 degrees. In the northern hemisphere in the summer, the axis is pointing its most toward the sun on June 21. On that day the most light reaches us and we experience the longest day of the year and warmer temperatures: the summer solstice.
The reverse is true on Dec. 21. Then the axis is pointing its most away from the sun,bringing less light and colder temperatures. That is the winter solstice,the longest night of the year.
It’s the opposite in the southern hemisphere,where Dec. 21 marks the longest day of the year and June 21 the shortest.
The midpoints,on March 20 and Sept. 22,are known as the equinoxes. On these days the axis is exactly in between and night and day are the same length,12 hours.
All these dates loom large in myth and folklore.
“Culturally,the solstices and equinoxes are typically used to denote either the beginnings of the seasons or the center points of the seasons,” as in England,says Rick Kline,with the Spacecraft Planetary Imaging Facility at Cornell University in Ithaca,N.Y.
Shedding some light on Dec. 21, winter’s darkest day