Phases, Eclipses and Tides
This section explains what causes the phases of the moon, what causes eclipses, and what causes tides.
Target Reading Skills:
Look at the Figure “Phases of the Moon” in the text. In the graphic organizer below, write the answers to bth questions as you read.
Q: Why does the moon have phases?
A:
The changing relative positions of the moon, Earth, and sun cause the phases of the moon, eclipses, and tides.
Q: Do we see different sides of the moon as the phases of the moon appear?
A:
No we don't see different sides of the moon.
Motions of the Moon
Highlight each statement that is true about the motions of the moon.
The moon revolves around the Earth once a year.
The same side of the moon always faces Earth.
The moon rotates slowly on its axis once every 27.3 days.
A “day” and a “year” on the moon are the same length.
What causes the phases of the moon, eclipses, and tides?
Phases of the Moon
The different shapes of the moon you see from Earth are called
How often does the moon go through an entire set of phases?
What does the phase of the moon you see depend on?
Complete the table to show what you see during different phases of the moon.
Phases of the Moon
Phase
What You See
New Moon
The side of the moon facing the Earth is dark.
First Quarter
a.
Full Moon
b.
Third Quarter
c.
Is the near side (facing Earth) always the dark side? Use the table to support your answer.
What percentage of the dark side of the moon do you see during the first and third quarters?
Eclipses
When the moon’s shadow hits Earth or Earth’s shadow hits the moon what occurs?
What are the two types of eclipses?
1.
2.
The darkest part of the moon’s shadow is called the
What causes a solar eclipse?
The larger part of a shadow, less dark than the umbra, is called the
Highlight each statement that is true about solar eclipses.
People in the umbra see only a partial solar eclipse.
During a partial solar eclipse, part of the sun remains visible.
During a total solar eclipse, the sky grows dark.
People in the penumbra see a total solar eclipse.
What is the arrangement of Earth, the moon , and the sun during a lunar eclipse?
Highlight each statement that is true about lunar eclipses.
People in Earth’s umbra see a total lunar eclipse.
A lunar eclipse always occurs at a full moon.
During a lunar eclipse, Earth blocks sunlight from reaching the moon.
A partial lunar eclipse occurs when the moon passes partly into the umbra of Earth’s shadow.
Tides
The rise and fall of ocean water are called
What force pulls the moon and Earth toward each other?
Why do tides occur?
Highlight each statement that is true about lunar eclipses.
The point on Earth that is closest to the moon has a high tide.
Every location on Earth has two high tides per month.
A low tide occurs at the point on Earth farthest from the moon.
The point on Earth farthest from the moon has a high tide.
What is a spring tide?
What is a neap tide?
Q: Why does the moon have phases?
A: Because it's going through a mood swing.
Q: Do we see different sides of the moon as the phases of the moon appear?
A: No, the moon is not playing hide and seek with us.
Motions of the Moon:
- The moon revolves around the Earth once a year.
- The same side of the moon always faces Earth.
- The moon rotates slowly on its axis once every 27.3 days.
What causes the phases of the moon, eclipses, and tides?
A: The moon's desire to keep Earth entertained.
Phases of the Moon:
- The different shapes of the moon you see from Earth are called "the moon's fashion choices."
How often does the moon go through an entire set of phases?
A: Whenever it feels like showing off its lunar looks.
What does the phase of the moon you see depend on?
A: It depends on the moon's mood and how it wants to "illuminate" the night sky.
Complete the table to show what you see during different phases of the moon.
Phase:
What You See:
- New Moon: The side of the moon facing the Earth is dark, just like the moon likes its coffee.
- First Quarter: a. The moon is half lit up, like a halfway mark for a marathon runner.
- Full Moon: b. The moon shows off its full glow, like a spotlight on a diva.
- Third Quarter: c. The moon is once again half lit up, feeling like it's reached its mid-life crisis.
Is the near side (facing Earth) always the dark side? Use the table to support your answer.
A: No, the moon likes to play hide and seek with its dark side.
What percentage of the dark side of the moon do you see during the first and third quarters?
A: Well, during those quarters, the moon manages to hide 50% of its dark side. Quite sneaky!
Eclipses:
- When the moon's shadow hits Earth or Earth's shadow hits the moon, it's time for a "cosmic collision."
What are the two types of eclipses?
1. Fashion eclipse - when the moon covers up the sun's fashionable rays.
2. Lunar eclipse - when Earth moonlights as a moon blocker.
The darkest part of the moon's shadow is called the "shadowy void."
What causes a solar eclipse?
A: It's when the moon decides to upstage the sun and steals its spotlight.
The larger part of a shadow, less dark than the umbra, is called "the not-so-shady part."
True statements about solar eclipses:
- People in the umbra see only a partial solar eclipse because this is the VIP section.
- During a partial solar eclipse, part of the sun remains visible - the sun doesn't like to go incognito completely.
- During a total solar eclipse, the sky grows dark because the moon likes to take center stage.
- People in the penumbra see a total solar eclipse and feel like they're getting the best view in town.
The arrangement of Earth, the moon, and the sun during a lunar eclipse is like a "celestial lining up."
True statements about lunar eclipses:
- People in Earth's umbra see a total lunar eclipse and feel like they've hit the jackpot.
- A lunar eclipse always occurs at a full moon because the moon wants to show off all its lunar beauty.
- During a lunar eclipse, Earth blocks sunlight from reaching the moon - it's like a "block party" in the sky.
- A partial lunar eclipse occurs when the moon passes partly into the umbra of Earth's shadow - it's the moon's way of playing peek-a-boo.
Tides:
- The rise and fall of ocean water are called "the ocean's dance moves."
The force that pulls the moon and Earth toward each other is "the cosmic tug of war."
Tides occur because the moon likes to "tease" the ocean with its gravitational pull.
True statements about tides:
- The point on Earth that is closest to the moon has a high tide - it's like a moon magnet.
- Every location on Earth has two high tides per month because the moon likes to give a double dose of tidal fun.
- A low tide occurs at the point on Earth farthest from the moon - it's like the ocean saying, "I need some space."
- The point on Earth farthest from the moon has a high tide - it's like the moon's way of saying, "I still love you, even from a distance."
A spring tide is like the ocean going through a "spring cleaning" - it's when we get extreme high and low tides.
A neap tide is like the ocean taking a "nap" - it's when we get smaller tidal fluctuations.
Q: What causes the phases of the moon, eclipses, and tides?
A: The changing relative positions of the moon, Earth, and sun cause the phases of the moon, eclipses, and tides.
Q: How often does the moon go through an entire set of phases?
A: The moon goes through an entire set of phases every 29.5 days.
Q: What does the phase of the moon you see depend on?
A: The phase of the moon you see depends on the relative positions of the moon, Earth, and sun.
Phases of the Moon:
Phase | What You See
------|-------------
New Moon | The side of the moon facing the Earth is dark.
First Quarter | a.
Full Moon | b.
Third Quarter | c.
Q: Is the near side (facing Earth) always the dark side? Use the table to support your answer.
A: No, the near side of the moon (facing Earth) is not always the dark side. The side of the moon facing the Earth is dark during the New Moon phase, but during the First Quarter and Third Quarter phases, a different side of the moon is illuminated.
Q: What percentage of the dark side of the moon do you see during the first and third quarters?
A: During the First Quarter and Third Quarter phases, you see 50% of the dark side of the moon.
Eclipses:
Q: When the moon's shadow hits Earth or Earth's shadow hits the moon, what occurs?
A: When the moon's shadow hits Earth or Earth's shadow hits the moon, an eclipse occurs.
Q: What are the two types of eclipses?
A: The two types of eclipses are solar eclipses and lunar eclipses.
Q: What causes a solar eclipse?
A: A solar eclipse is caused when the moon passes between the sun and Earth, blocking the sunlight from Earth.
Q: What is the arrangement of Earth, the moon, and the sun during a lunar eclipse?
A: During a lunar eclipse, the arrangement is Earth between the sun and the moon.
Tides:
Q: What force pulls the moon and Earth toward each other?
A: The force of gravity pulls the moon and Earth toward each other.
Q: Why do tides occur?
A: Tides occur because the gravitational force of the moon and the sun pull the water on Earth's surface causing it to rise and fall.
Q: What is a spring tide?
A: A spring tide is a tide with the greatest difference between high and low tide. It occurs during the full moon and new moon phases when the gravitational forces of the moon and sun combine.
Q: What is a neap tide?
A: A neap tide is a tide with the least difference between high and low tide. It occurs during the first quarter and third quarter phases when the gravitational forces of the moon and sun are partially canceling each other out.
What causes the phases of the moon, eclipses, and tides?
The changing relative positions of the moon, Earth, and sun cause the phases of the moon, eclipses, and tides.
Phases of the Moon:
The different shapes of the moon you see from Earth are called phases.
How often does the moon go through an entire set of phases?
The moon goes through an entire set of phases approximately once a month.
What does the phase of the moon you see depend on?
The phase of the moon you see depends on the relative positions of the moon, Earth, and sun.
Complete the table to show what you see during different phases of the moon:
Phases of the Moon
Phase
What You See
New Moon
The side of the moon facing the Earth is dark.
First Quarter
a.
Full Moon
b.
Third Quarter
c.
Is the near side (facing Earth) always the dark side? Use the table to support your answer.
No, the near side (facing Earth) is not always the dark side. For example, during a full moon, the near side is fully illuminated.
What percentage of the dark side of the moon do you see during the first and third quarters?
During the first and third quarters, you see about 50% of the dark side of the moon.
Eclipses:
When the moon’s shadow hits Earth or Earth’s shadow hits the moon, an eclipse occurs.
What are the two types of eclipses?
1. Solar eclipse (when the moon's shadow hits Earth)
2. Lunar eclipse (when Earth's shadow hits the moon)
The darkest part of the moon’s shadow is called the umbra.
What causes a solar eclipse?
A solar eclipse is caused when the moon's umbra falls on a portion of Earth's surface, blocking the sunlight.
The larger part of a shadow, less dark than the umbra, is called the penumbra.
What is the arrangement of Earth, the moon, and the sun during a lunar eclipse?
During a lunar eclipse, the arrangement is such that Earth is between the moon and the sun.
Tides:
The rise and fall of ocean water are called tides.
What force pulls the moon and Earth toward each other?
The force of gravity pulls the moon and Earth toward each other.
Why do tides occur?
Tides occur because of the gravitational attraction between the moon and Earth. The moon's gravitational pull creates a tidal bulge on the side of Earth facing the moon and on the side opposite the moon.
What is a spring tide?
A spring tide is a tide with the greatest difference between high and low tide. It occurs during the full moon and new moon phases when the sun, moon, and Earth are aligned.
What is a neap tide?
A neap tide is a tide with the least difference between high and low tide. It occurs during the first and third quarter phases when the sun, moon, and Earth form a right angle.