Students find a similar mirror pattern as they did with temperature in this activity, “Days and Nights Around the World (Activity Six).” They graph and analyze Sun position data (sunrise and sunset times and positions, as well as how high the Sun gets at noon) from cities around the world.

Where is the Sun in the sky at a particular time and day? A Sun angle calculator is used by architects designing solar heated buildings and by others who need to be able to predict the Sun’s position. On a Sun angle calculator you set the latitude of your position, and the day and time. The calculator will tell you the elevation of the Sun, and its angle from north, or azimuth. (Web link requires an Internet connection)	The Starry Night program allows you to see the position of the Sun (or Moon and stars) at any time, for any particular location on Earth. It even allows you to go back or forward in time.

This movie shows the position of the Sun from sunrise to sunset at a 20 minutes intervals at the Arctic Circle. The location chosen was 66 degrees 33 minutes north latitude, 0 degrees west longitude. This is a point in the Norwegian Sea about halfway between Norway and Iceland. The time advance is 20 minutes per frame, starting at March 21, 2000 4:00A.M, the first day of spring. This movie was made from a series of 50 pictures.     View the Earth rotation below you. The start time March 21, 2000 at 6:26 P.M. Viewpoint elevation is 15,814 km. The time step is one frame per 30 minutes.     This movie shows how light falls on the area north of the Arctic Circle on the longest day of the year. The Sun is visible 24 hours per day. Start time is June 21. 2000 at 12:00 A.M. The time step is one frame per 30 minutes. The movie shows 24 hours of elapsed time.

The position of the Sun at Cape Cod, Massachusetts. Location is 42 N Latitude, 70 degrees W Longitude. The frames are every six days, 10 minutes after Sunrise for a full year, starting on January 1, 2000. Notice that the Sun only rarely rises due east, How far north of east does it set?     The position of the Sun at noon each day of the year looking south from Berkeley, California. The Sun’s altitude in the southern sky changes due to the tilt of the Earth’s axis of rotation. Notice that the Sun is sometimes east and sometimes west of due south at noon as well. The Sun’s changing position east or west of due south at noon is due to the ellipticity (non-circularity) of the Earth’s orbit around the Sun. The Earth moves faster around the Sun when it is closer to the Sun and slower when it is further away. One rotation of the Earth in a day (24 hours) does not bring the Sun to the same position in the sky (due south) at different times of the year. The Sun’s changing position throughout the year can be described by an analemma or figure–8–shaped curve found on some globes. The movie was made from a set of 12 jpegs, over every 3rd day for a year, starting at 12 noon January 1, 2000.

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