ASTRONOMY

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ASTRONOMY
SECTION 2 PHASES, ECLIPSES TIDES
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Phases, eclipses tides are caused by the
positions of the moon, Earth, sun.
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The moon makes one revolution around the Earth
every 27. 3 days. The moon rotates once on its
axis every 27.3 days as well. Because of this,
the same side of the moon always faces the Earth.
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The phases of the moon that we see depend on how
much of the sunlit side of the moon faces the
Earth.
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COMPLETE MOON PHASE CHART NOW. USE PAGE J26 TO
HELP.
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• Any time an object in space comes between the sun
  a third object, an eclipse occurs.
• There are 2 kinds of eclipses
• Solar
• Lunar

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A solar eclipse happens when the moon passes
between the Earth and the sun. During this, the
moon casts its shadow on Earths surface.
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This is what a total solar eclipse would look
like from Earth.
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• The moons shadow has 2 parts
• The umbra - the darkest part
• 2. The penumbra - larger than the umbra and less
  dark.

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This is a photo of the 1999 solar eclipse taken
from the Mir space station. Notice the dark
umbra and the grayish penumbra around it.
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A lunar eclipse happens at a full moon when Earth
is between the moon and the sun. During this,
the Earth casts a shadow on the moon.
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As the moon orbits Earth, its gravity pulls the
water in the oceans towards it. This pulling /
moving of the oceans waters is called the tidal
cycle. The tidal cycle causes high tides and low
tides about every 12 hours.
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2 times each month, the moon, Earth, sun line
up and cause an extra high tide called a spring
tide.
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2 other times each month, the moon, Earth, sun
are at right angles to each other. We still have
a high low tide, but the high tide is lower
than normal. This is called a neap tide.
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End of Section Two