Everybody in the solar system carries a shadow along with it as it moves around the Sun. A shadow is formed when an object blocks a light source. When one body enters the shadow of another, an eclipse occurs. The moon phase activities mentioned above will stimulate students in understanding the simulation of both lunar and solar eclipses.
OBJECTIVES
Students will be able to:
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distinguish between lunar and solar eclipse
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model how lunar and solar eclipses occur
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predict when an eclipse is most likely to occur
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As the moon revolves around the earth, it usually passes above or below the earth's shadow. Sometimes the moon passes directly through the earth's shadow. As a result sunlight is blocked from reaching the moon. When sunlight is blocked from the moon, a lunar eclipse occurs. That is the earth's shadow falls on the moon and will darken significantly, but not disappear. The dark part of a shadow is called the umbra and the lighter part of the shadow is called the penumbra. Sometimes the moon moves entirely into the earth's umbra. When this happens, all of the sun's light is blocked. The entire face of the moon darkens. This is called a total lunar eclipse. At other times only part of the moon moves into the earth's umbra. However, sunlight can still reach the moon. As a result, only part of the moon darkens. This is called a partial lunar eclipse.
Solar eclipses occur when the moon passes between the sun and the earth, temporarily blocking sunlight over a small portion of our planet's surface. The shadow of the moon usually moves from West to East across the earth . People in the path of the shadow may see one of three kinds of solar eclipse. Namely, (a) total
eclipse , (b) annular eclipse or (c) partial eclipse. A total eclipse occurs if the moon completely blots out the Sun. If the moon is at its farthest point from the earth when a total eclipse occurs, the eclipse may be only an annular eclipse . In such an eclipse, the moon darkens only the middle of the Sun, leaving a bright ring around the edges. A partial eclipse occurs if the moon covers only part of the Sun.
A solar eclipse should never be viewed directly. One must be careful to avert his or her eyes when a sliver of the photosphere becomes visible.