Objective
Students will understand that the appearance of the moon changes in a predictable cycle as
it orbits Earth and as Earth rotates on its axis.
Phases of the Moon Fact Sheet
Gibbous – Between half and full.
Orbit - The path that a planet (or a moon) travels as it goes
around the Sun (or a moon its planet).
Phases of the Moon - The changes in the appearance of the Moon’s shape during a
month, such as New Moon, Waxing Crescent, First Quarter, Gibbous Waxing, Full
Moon, Gibbous Waning, Last (Third Quarter), Waning Crescent.
1
Objective
Students will understand that the appearance of the moon changes in a predictable cycle as
it orbits Earth and as Earth rotates on its axis.
(Diagram not to scale)
Sunlight Reflecting Off Moon
Sunlight
Reflection - The bouncing of light off an object. The Moon appears to shine
because it reflects the Sun’s light.
Revolution - The circling of one object around another object in space. A planet
revolves around the Sun. A moon revolves around a planet. Earth revolves around
the Sun counterclockwise. The Earth takes 365 ¼ days to revolve once around the
Sun. The Moon takes about 27.5 days to revolve once around the Earth.
2
Objective
Students will understand that the appearance of the moon changes in a predictable cycle as
it orbits Earth and as Earth rotates on its axis.
Axis
Axis
Rotation - When a planet or moon turns all the way around or
spins on its axis one time. Earth & Moon rotate
counterclockwise. Earth rotates once every 24 hours. The
Moon rotates once every 27.5 days.
Waning – Getting
smaller; the left side
of the Moon is in
sunlight; the right
side of the Moon is
becoming dark.
Waxing – Getting larger; the
right side of the Moon is in
sunlight; the right side of the
Moon is becoming bright.
3
Objective
Students will understand that the appearance of the moon changes in a predictable cycle as
it orbits Earth and as Earth rotates on its axis.
Eight Key phases of the Moon
New Moon
Waxing Crescent
First Quarter
Gibbous Waxing
Full Moon
Gibbous Waning
Last Quarter
Waning Crescent
We see phases of the Moon because the
Moon revolves around the Earth. The
position of the Earth, Moon, and Sun is
responsible for each phase of the Moon.
4
Objective
Students will understand that the appearance of the moon changes in a predictable cycle as
it orbits Earth and as Earth rotates on its axis.
The diagram shows the position of the Moon, Sun, and Earth at each phase. The
amount reflecting off the Moon is responsible for us seeing phases of the Moon.
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