1. Unit 2 Lesson 3 What Are Moon Phases?
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2. Unit 2 Lesson 3 What Are Moon Phases?
Florida Benchmark
SC.4.E.5.2 Describe the changes in the observable shape of the moon over the course of about a month.
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3. Our Moon The moon is Earth’s satellite.
Unit 2 Lesson 3 What Are Moon Phases?
Our Moon
The moon is Earth’s satellite.
A satellite is an object that moves around another larger object in space.
The surface of the moon has mountains and plains.
There are craters on the surface due to debris from space striking it.
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4. Our Moon The moon is the largest, brightest object in the night sky.
Unit 2 Lesson 3 What Are Moon Phases?
Our Moon
The moon is the largest, brightest object in the night sky.
We see the moon because light from the sun reflects from it and back to Earth.
The pull of Earth’s gravity keeps the moon in orbit around Earth.
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5. Unit 2 Lesson 3 What Are Moon Phases?
Our Moon
The moon is about one-fourth the size of Earth. It has no air, wind, or liquid water.
Only one side of the moon is seen from Earth. This is because the moon takes the same amount of time to rotate once as it does to orbit Earth once.
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6. Unit 2 Lesson 3 What Are Moon Phases?
The changes in the appearance of the moon’s shape are known as phases.
The motions of the Earth and moon are responsible for the phases.
It takes about a month for the moon to complete all of its phases.
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7. Unit 2 Lesson 3 What Are Moon Phases?
Different amounts of the moon’s lit side are seen from Earth as the moon goes through phases.
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8. Lunar and Solar Calendars
Unit 2 Lesson 3 What Are Moon Phases?
Lunar and Solar Calendars
People use the phases of the moon and Earth’s orbit around the sun to make calendars and to track time.
Our modern calendar is based on Earth’s orbit around the sun and the moon’s phases.
Calendars based on Earth’s orbit are called solar calendars.
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9. The Chinese Zodiac Calendar
Unit 2 Lesson 3 What Are Moon Phases?
The Chinese Zodiac Calendar
The Chinese zodiac calendar is based in part on the phases of the moon.
Cycles of time on the Chinese calendar are named after different animals.
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