As you watch over the course of a month, you will see that the Moon changes shape

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Chapter 3

• As you watch over the course of a month, you will
  see that the Moon changes shape
• You may notice that it rises about 45 minutes
  earlier each night as it moves eastward
• The changes in shape are called the phases of the
  Moon
• The phases are actually due to the geometry of
  the Sun, the Moon, and the Earth

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• How much of the Moon is illuminated at any one
  time?
• KNOW THE PHASES OF THE MOON
• From the Earth we see only one side of the Moon
  ever
• This is because the rotation of the Moon is equal
  to the revolution of the Moon
• Another thing that the Moon is involved with are
  eclipses

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• The 2 basic types of eclipses are the lunar
  eclipse and the solar eclipse
• The name tells you what is being eclipsed
• A lunar eclipse is where the Sun, Moon and Earth
  line up perfectly so that the Moon goes into the
  Earths shadow

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• A lunar eclipse may last for up to 1 hour and 40
  minutes
• This is because the shadow is about 3 times
  bigger than the Moon

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• There are 2 parts to the shadow called the umbra
  and the penumbra
• The umbra is the darkest part of the shadow
• This is where you will see the Moon disappear
• When the Moon is in the penumbra, it will dim
  slightly and it wont be all that spectacular

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• A solar eclipse is when the Moon goes in between
  the Earth and the Sun
• The maximum length of a solar eclipse is about 7
  minutes
• For this to happen the Sun and Moon are both
  about the same size in the sky
• They are both about .5 in size
• Just like a lunar eclipse, you have an umbra and
  a penumbra
• There are 2 kinds of solar eclipse a total and
  an annular

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A total eclipse
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Eclipse in Paradise -- Aruba
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Partial Solar Eclipse
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• The other kind of solar eclipse is called an
  annular eclipse
• This is where the Moon is a little farther away
  from the Earth and it appears smaller than the
  Sun
• This is where you would get a ring of Sun

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• During an eclipse you may see several things
• The most obvious is the white crown around the
  Sun called the corona
• You may also see a red ring around the Sun and
  this is the chromosphere
• Normally you dont see either one of these
  because the Sun is too bright
• You dont have eclipses each month because the
  orbit of the Moon is tipped at about 5

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• This means that the eclipses only occur when the
  Sun, Moon, and Earth line up perfectly
• This means that there are eclipse seasons, times
  where eclipses are more likely to occur

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Solar Eclipse From Space
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• It has been determined that the pattern of
  eclipses repeats itself
• It is called the Saros Cycle
• The repetition occurs every 18 years and 11.33
  days
• Thales of Miletus predicted a solar eclipse on
  May 28, 585 BC
• The Lydians and the Medes were about to battle
  and when it occurred they were so frightened that
  they signed a truce