Because of the ro
tation of the Earth, the Sun appears to move across the sky from east to west. In the morning when the Sun rises above the eastern horizon, it is at a low altitude (angular height above the horizon), shadows are long.
Sunrise is when the Sun rises above the eastern horizon.
At sunrise, the Sun is at its lowest altitude (angular height above the horizon).
The Sun continues to rise in the sky until it reaches its highest altitude, which by Sun time is noon.
After noon, the Sun moves toward the western horizon. This means its altitude decreases.
Sunset is when the Sun sinks below the western horizon.
 Shadows form when an object blocks a light source. Sun shadows are longest at sunrise and at sunset. Sun shadows are shortest at noon. Sun shadows point west at sunrise.Sun shadows point east at sunset At Earth’s equator, there is no shadow at noon. North of the equator (the Northern Hemisphere) shadows at noon point North. South of the equator (the Southern Hemisphere) shadows at noon point South.
Discover for Yourself You can demonstrate shadow length and direction at the equator: 1. Draw two perpendicular lines across the center of a sheet of paper. 2. Print the compass directions, N, E, S, W on the ends of the lines as shown. 3. Use clay to stand a pencil where the lines cross. 4. In a darkened room, hold the flashlight on the east side and about 6 inches (15 cm) away from the pencil. The light should be pointed toward the side of the pencil. Observe the length of the shadow. 5. Slowly move the flashlight in a semicircle over the pencil. Observe the length and direction of the pencil’s shadow during this movement. Determine the position of the flashlight that would result in shadows in the Northern Hemisphere and in the Southern Hemisphere. For more information about Sun Shadows, see Janice VanCleave’s Earth Science for Every Kid.
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