aim: what makes the moon appear to change shape?
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Aim: What makes the moon appear to change shape?. Do Now: What are the four seasons and why do we have them? Homework: Handout 17-5 & 17-6. What are the 2 motions of the moon?. Rotation & Revolution. How long does it take the moon to rotate once?. - PowerPoint PPT PresentationTRANSCRIPT
Aim: What makes the moon appear to change shape?
Do Now: What are the four seasons and why do we have them?
Homework: Handout 17-5 & 17-6
What are the 2 motions of the moon?
Rotation & Revolution
How long does it take the moon to rotate once?
It takes the moon 27 1/3 days to rotate once on its axis
Why do we always see the same side of the moon?
The moon’s period of rotation & revolution are both 27 1/3 days
Therefore:
The same side of the moon is always facing the earth
How do we describe the moon’s position relative to the earth?
Apogee- When the moon is farthest (away) from the earth
Perigee- When the moon is closest to the earth
Which photoshows apogee?
When does the moon rise and set each day?
50 minutes later each day
It takes this much time for the moon to catch up to the revolution of the earth.
Why does the moon appear to change shape?
a) The change in shape is because of the way the moon reflects light from the sun &
b) How we see it from the earth as it revolves in its orbit around the earth
c) The changing shapes of the moon are called phases.
What is the difference between a waxing & waning moon?
a) Waxing Phases – part of the moon that is visible increases
b) Waning Phases – part of the moon that is visible decreases
What are the phases of the moon?
1. New Moon – there appears to be no moon at all (Sun, Moon, Earth)
2. Waxing crescent phase – less than half the moon is visible from the earth
3. First Quarter – there appears to be half a moon
4. Waxing gibbous phase – more than half the moon is visible
5. Full Moon – whole face of the moon is visible (Sun, Earth, Moon)
6. Waning gibbous phase - more than half the moon is visible
7. 3rd Quarter - there appears to be half a moon
8. Waning crescent phase – less than half the moon is visible from the earth
What is today’s phase of the moon?
Aim: Lab: What makes the moon appear to change shape?
Do Now: Prepare for quiz
Homework: Study for quiz
The Moon's Phase
SUMMARY…• Compare apogee and perigee.
• Why do we always see the same side of the moon?
• How long does it take the moon to complete one revolution around the earth? Rotation?
• Why does the moon appear to change shape?
Motions of the Earth & Moon: Quiz #1
1. The movement of the earth around the sun iscalled _______________.
2. Day & night are caused by the earth’s _______.
3. The North Pole of the earth points toward___________.
4. The earth rotates on its axis from _______ to ________.
5. During the _________, the earth receives slanted rays from the sun.
6. What is the date of the earth at point A?
A
B
C
D
E
7. What season is the Southern Hemisphere having at point C?
8. Is point E considered to be aphelion or perihelion?
A
B
C
D
E
9. When the part of the moon that is visible increases the moon is said to be in its (waxing/waning) phase.
10. When there appears to be no moon at all &the Sun, Moon & Earth are all aligned the phase of the moon is the ________ moon.
Aim: How does an eclipse occur?
Do Now: List the phases of the moon.
Homework: Handout 17-7 & 17-
8
How does an eclipse of the moon occur?
A lunar eclipse occurs when the moon passes through the earths shadowCan only occur during a full moon
Observe a lunar eclipse.
(Sun Earth Moon)
What are the two parts of a shadow?
1. The umbra – the very dark center
2. The penumbra- the outer lighter part of the shadow
What is the difference between a total lunar eclipse and a partial lunar eclipse?
Total Lunar Eclipse – The moon moves entirely into the earths umbra
Partial Lunar Eclipse – When only part of the moon moves into the earths umbra
Sunlight can still reach the moon
How does an eclipse of the sun occur?
Observe solar eclipses.http://riker.ps.missouri.edu/RICKSPAGE/Moon/SolarEclipse.html
A Solar Eclipse occurs when the moon passes between the earth and the sun.
The moon cast a shadow on the earth.
Sun Moon Earth
Solar Eclipse
What is the difference between a total solar eclipse and a partial
solar eclipse?Total Solar Eclipse –1. The entire face
of the sun is blocked by the moon
2. Caused by the umbra
3. Visible from only a small part of the earth
Partial Solar Eclipse-1. Only part of the
suns face is blocked
2. Caused by the penumbra
3. Seen over a larger area of earth
Let’s Review…•What causes a lunar eclipse?•Explain the difference between umbra and penumbra.
•Where do you have to live on earth to see a total solar eclipse?
Aim: How does the moon affect the
tides?Do Now: Draw a lunar eclipse (include umbra & penumbra)Homework:Handout (17-
9 & 17-10)
Phases of Moon & Eclipses: Quiz #11. When the part of the moon that is visible
increases it is said to be (waxing/waning).2. When the Sun, Moon & Earth are all aligned
the phase of the moon is the (Full/New) moon.3. The darkest part of a shadow is called the
(umbra/penumbra).4. An eclipse that occurs during the Full Moon
phase is (solar/lunar).5. When the moon’s penumbra touches the
earth, people within the penumbra see a (total/partial) solar eclipse.
What are tides?
What causes the tides?
The changes in ocean water levels
Low water level = Low Tide
High water level = High Tide
The moons gravitational force pulls the water in the ocean toward the moon.
Tidal Bulge
High Tide
TidesLow Tide
How do the tides change?
2 high tides & 2 low tides occur each day
Flood tide = incoming tide Ebb tide = outgoing tide
What are Spring Tides?
When the tides are higher and lower than normal tides.
This is due to the earth, sun & moon lining up in a straight line (↑ gravity)
Spring Tide
When are the 2 times in a month when the earth, sun &
moon line up in a straight line?
Spring Tide
What are Neap Tides?
Tides that are not as high or as low as usual
Occurs during the moon’s first and last quarter
The sun and the moon are at right angles to the earth
Neap Tide
SUMMARY•How many tides do we have a
day?•What causes the tides?•What is the difference between
a spring tide and a neap tide?•How does the earth, sun and
moon line up during a neap tide?
Tides
Tides: Quiz #1
1. An incoming or rising tide is known as a _____tide.
2. A daily change in the level of the earth’s oceans is called __________.
3. Tides that are not as high or as low as normal are called ________ tides.
4. During what phases of the moon do Spring tides occur?
5. What causes tides to occur?