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Plotting the Position of the Sun
Print the city scape or worksheet one, then plot the positon
of the sun at noon on the equinoxes and solstices.
When the students are finished, they will use worksheet two to plot
the position of the sunset and sunrise on the solstices and equinoxes.
Background:
"When the sun comes back" teaches us that slaves knew how to use the sun
as a calendar. During winter and spring the sun's altitude is higher and
higher each day at noon. In fall and summer it is lower. This is because
Earth has seasons. Seasons occur because Earth is traveling around the
sun, and because Earth is tilted 23 and 1/2 degrees on its axis. When
the North Pole is tilted towards the sun, the Northern Hemisphere receives
more hours of sunlight per 24-hour period than the Southern Hemisphere.
During this period, December 21 to June 21, the sun is higher and higher
in the sky each day at noon. Its maximum height occurs on June 21, the
summer solstice. After this date, the sun seems slightly lower each day,
and the Southern Hemisphere is beginning to receive more light. By September
21, the fall equinox, sunlight falls equally north and south of the equator.
By December 21, the winter solstice, the South Pole is tilted toward the
sun, and the Southern Hemisphere has its longest day, and the Northern
Hemisphere its shortest. Then the pattern reverses, and by March 21, the
spring equinox, sunlight falls equally north and south of the equator.
On December 21, those of us living in the Northern Hemisphere see the
sun rise in the southeast and set in the southwest. On succeeding days,
sunrise and sunset are a little further and further north. On March 21,
sunrise and sunset are straight east and west. On June 21, they are in
the northeast and northwest. Then the pattern reverses, and by September
21, sunrise and sunset again are due east and west.
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