Transcript phase - Kawameeh Middle School

Earth’s Moon
• How does the Moon move around
Earth?
• Why does the Moon’s appearance
change?
Earth’s Moon
• maria
• phase
• waxing phase
• waning phase
Seeing the Moon
• The Moon does not emit any light
• You only see the Moon because light
from the Sun reflects off the Moon and
into your eyes.
The Moon’s Formation
The most widely accepted idea for the
Moon’s formation is the giant impact
hypothesis.
The Moon’s Formation
According to the giant impact hypothesis,
shortly after Earth formed about 4.6 billion
years ago, an object about the size of the
planet Mars collided with Earth.
The Moon’s Formation (cont.)
The impact ejected vaporized rock that
formed a ring around Earth.
The Moon’s Formation (cont.)
Eventually, the material in the ring cooled
and clumped together and formed the
Moon.
The Moon’s Formation (cont.)
• The surface of the Moon was shaped
early in its history. (Click the picture of the moon to
see a video that shows the shaping of the moon’s surface)
• Moon’s craters were formed when
objects from space crashed into the
Moon.
• The large, dark, flat areas on the Moon
are called maria.
• Maria formed when lava flowed up
through the Moon’s crust and solidified.
The Moon’s Motion
• While Earth is revolving around the
Sun, the Moon is revolving around
Earth.
• The Moon rotates as it revolves around
Earth.
• One complete rotation of the Moon
takes 27.3 days, meaning the Moon
makes one rotation in the same
amount of time that it makes one
revolution around Earth.
The Moon’s Motion (cont.)
• Because the Moon takes the same
amount of time to orbit Earth and make
one rotation, the same side of the
Moon is always facing Earth.
• This side of the Moon is called the near
side.
• The side of the Moon that cannot be
seen from Earth is called the far side of
the moon.
The Moon’s Motion (cont.)
Phases of the Moon
The lit part of the Moon or a planet that can
be seen from Earth is called a phase.
The motion of the Moon around Earth
causes the phase of the Moon to change.
Jason Reed/Photodisc/Getty Images
Phases of the Moon (cont.)
• The sequence of phases is the lunar
cycle.
• During the waxing phases, more of
the Moon’s near side is lit each night.
• During the waning phases, less of the
Moon’s near side is lit each night.
Phases of the Moon (cont.)
• New Moon: the near side of the Moon
is completely dark
• Waxing Crescent: The portion of the
Moon you can see is waxing, or
growing into a crescent shape.
• First Quarter: You can see half of the
sunlit side of the Moon.
• Waxing Gibbous: the Moon continues
to wax. The visible shape of the Moon
is called gibbous.
Phases of the Moon (cont.)
• Full Moon: the entire near side of the
Moon is lit.
• Waning Gibbous: the portion of the
Moon you can see wanes, or shrinks.
• Third Quarter: You can see half of the
Moon’s lighted side.
• Waning Crescent: you see a crescent
once again.
Phases of the Moon rap!
Phases of the Moon (cont.)
• According to the giant impact
hypothesis, a large object collided
with Earth about 4.5 billion years ago
to form the Moon.
• The Moon’s phases
change in a regular
pattern during the
Moon’s lunar cycle.
Jason Reed/Photodisc/Getty Images
• Features like maria, craters, and
highlands formed on the Moon’s
surface early in its history.
19. What term is given to the side
of the Moon always facing Earth?
A. far side
B. phase
C. near side
D. maria
20. Which of these is
characterized by more of the
Moon’s near side being lit each
night?
A. waxing phase
B. waning phase
C. lunar cycle
D. full moon
Do you agree or disagree?
21. The Moon was once a planet that
orbited the Sun between Earth and
Mars.
22. Earth’s shadow causes the
changing appearance of the Moon.