What is a Lunar Eclipse

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"What is a Lunar Eclipse"
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The definition of a lunar eclipse is when the moon moves into the shadow of the Earth created by the sun, therefore, distorting its image and color. There are three basic types of lunar eclipses: the penumbral eclipse, a total eclipse, and a partial eclipse. When an eclipse occurs there will always be a full moon

The penumbra is the large outside part of the Earth's shadow that still receives solar radiation, but not much. A partial penumbral eclipse is when part of the moon is in the penumbra of the Earth's shadow. A partial penumbral eclipse doesn't show any noticeable darkening of the moon's surface, but my turn it slightly yellow. A total penumbral eclipse is very rare. This type of eclipse occurs when the moon is completely in the penumbra of the Earth's shadow, but not in the umbra. The color of the moon still remains slightly yellow, but the side of the moon closest to the umbra is darker.

A normal partial lunar eclipse is when the moon is partial in the umbra and the penumbral part of the Earth's shadow. The umbra is the tiniest sliver directly behind the earth that receives the minimum solar radiation. During a partial eclipse the moon turns a deep red or rust color. The color is deepest on the side of the moon that entered the umbra.

A total lunar eclipse is when the moon is completely inside the umbra of the Earth's shadow. This can occur only when the Sun, Earth, and Moon are aligned exactly, or very closely so, with the Earth in the middle. The color of the moon usually turns a deep orange. The average speed of the moon traveling through the umbra is about 1 kilometer per second depending on how far away the moon is from the Earth at that time. It can take the moon about 107 minutes to travel through the umbra, but takes over 3 hours to pass through the entire shadow.

The reason the moon changes colors during the eclipses is because of the tiny amount of light they receive from the sun has been bent around the earth. When light hits objects it bends, therefore, distorting its color. When the Moon is in the darkest part of Earth's shadow it can have some beautiful colors.

There are usually 2-3 different types of lunar eclipses throughout each year, but never more than three. The next partial eclipse of the Moon will occur on December 31, 2009. The next total eclipse of the Moon will occur on December 21, 2009. The next penumbral eclipse will occur on July 7, 2009. A lunar eclipse is visible over the entire night side of a hemisphere.

More about this author: Kimberly Humphrey

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