How are the motions and positions of
Earth and the Sun connected to what
happens on Earth?
• Earth’s rotation on its axis determines the
length of the day.
• Earth’s orbit around the Sun determines the
length of the year.
• The tilt of Earth’s rotational axis with respect
to the plane of Earth’s orbit causes the
seasons.
The changing phases of the Moon originally
inspired the concept of the month
Moon Phase Names
•
•
•
•
•
•
•
•
New Moon
Waxing Crescent
First Quarter
Waxing Gibbous
Full Moon
Waning Gibbous
Third Quarter
Waning Crescent
Watch Movie at:
http://antwrp.gsfc.nasa.gov/apod/image/9911/lunation_ajc.gif
The Causes of Moon Phases
• Think to yourself about the answer to this question:
What causes the phases of the Moon?
Take out a piece of paper and quickly write out a
brief answer.
How long does it take to complete
the full cycle of Moon Phases?
A. About a day
B. About a week
C. About a month
D. About a year
E. None of the above
Check your answer with your partner!!
Although the
Moon is always
½ lit by the
Sun, we see
different
amounts of the
lit portion from
Earth
depending on
where the
Moon is
located in its
orbit.
Let’s Watch some Moon Phase
Animations!
Pay attention to where the Moon, Sun and Earth are
located and how the Moon appears from Earth at each of
these positions.
Look at how much of the Moon is illuminated when at
each position.
Look at which side of the Moon is illuminated when at
each position.
http://astro.unl.edu/naap/lps/animations/lps.swf
Although the
Moon is always
½ lit by the
Sun, we see
different
amounts of the
lit portion from
Earth
depending on
where the
Moon is
located in its
month-long
orbit.
How many phases shown in the
picture at the right will the Moon go
through in one day?
How long does it take the Earth to
complete one rotation? How far will
the Moon have moved?
How long does it take the Moon to
complete one orbit? How many of
the phases will the Moon have gone
through in this time?
How much of the Moons total surface
is illuminated when it is in the New
Phase? Full Phase?
How much of the illuminated surface
of the Moon is visible from Earth
when it is in the First Quarter Phase,
Full Phase?
What time is it when the Waxing
Gibbous Phase is highest in the sky,
Rising? Setting? What phase will it
be in one week later….
What time is it
when the
waxing
crescent moon
is highest in the
sky? When
does it first
rises? When
does it set?
What time is it
when the
waxing
crescent moon
is highest in the
sky? When
does it first
rises? When
does it set?
What time is it
when the
waxing
crescent moon
is highest in the
sky? When
does it first
rises? When
does it set?
What moon
phase would be
rising in the
East at 3pm?
What Moon
phase would be
setting in the
West at 3pm?
The Moon Phase is highest in the
sky at 9pm today. What phase
will the Moon be in three weeks
after today?
Which Moon position (A-E), shown in the diagram at
right, best corresponds with the moon phase shown
below?
C
Earth
Sun
B
A
D
E
Orbit of the Moon
If the Moon were in the phase shown above, what phase
would it be in two weeks later?
Which of the situations shown above occurs at a time
closest to sunset?
If the moon is in the Full phase today, how many of the
moon phases shown above would the moon go through
during the next 11 days.
A. only one
B. two
C. three
D. more than three
E. none
Which of the following groups of moon phases can be seen
(above the horizon) at 3:00 am?
A. Third Quarter, Waning Crescent, and Waxing Crescent
B. New Moon, First Quarter, and Waxing Gibbous
C. Third Quarter, Full Moon, Waning Gibbous
D. Waxing Crescent, First Quarter, Waxing Gibbous
E. None of the above is correct