Unit 8 Lesson 1 How Do Earth and the Moon Move? · •The part of Earth that points away from the sun gets less sunlight. The part with the least direct sunlight experiences winter

Unit 8 Lesson 1 How Do Earth and the Moon Move?

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Rotates SpinsTurns


Turning Through the Day


• Looking at the Earth from above the North Pole, we see that Earth turns in the opposite direction to a clock.

• As Earth turns, half of it gets light from the sun, and half of it is in darkness.

• It is day on the lit half of Earth, and night on the dark half. Day changes to night as Earth turns.




• Picture a line going through Earth from the North Pole to the South Pole. This imaginary line is Earth’s axis.

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• Picture a line going through Earth from the North Pole to the South Pole. This imaginary line is Earth’s axis.

• Like a wheel on a bike, Earth rotates, or turns, on its axis.

• Earth’s rotation causes the cycle of day and night. One full rotation takes 24 hours, or one full day.

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Reasons for Seasons


• As Earth turns on its axis, it also moves around the sun.

• Each complete trip around the sun is one revolution.

• Each revolution takes about 365 days, or one year.








Reasons for Seasons


• How does Earth’s tilt on its axis affect the amount of sunlight different parts of the planet receive?


Reasons for Seasons


• The part of Earth that points toward the sun gets more direct sunlight. The part with the most direct sunlight experiences summer.

• The part of Earth that points away from the sun gets less sunlight. The part with the least direct sunlight experiences winter.

• During fall and spring, neither the top nor the bottom half of Earth is tilted toward or away from the sun.


Reasons for Seasons


Winter Days!


• What is winter like for kids in the United States? That depends on where you live.

• In Phoenix, Arizona, winter temperatures are usually in the 60s or 70s.

• But someone in Madison, Wisconsin, would be used to temperatures in the 20s or 30s.



Phases of the Moon


• Does moonlight really come from the Moon? No!

• The moon doesn’t produce its own light. Moonlight reflects from the sun.

• The reflected light is what we see from Earth. At any time, half of the moon is lit by the sun.


Phases of the Moon


• As the moon revolves around Earth, different amounts of its lit side can be seen. This is what causes the different shapes, or phases, of the moon.

• Eight moon phases make up one cycle. A full cycle happens in about one month. Then the cycle repeats.


Phases of the Moon


• The four main moon phases are new moon, full moon, and both quarter moons.

• A first-quarter moon looks like a half-circle and is lit on the right side.


Phases of the Moon


• As we see more of the moon’s lit side, we say that the moon is waxing.

• As we see less of the moon’s lit side, we say that the moon is waning.


Phases of the Moon



Daily Highs and Lows


• The pull of the moon’s gravity causes ocean tides.

• Tides are changes in the height of ocean water.

• When the moon is above an ocean, the moon causes high tide on that part of Earth and on the opposite side, too.




• In the parts of the ocean between the two areas of high tide, the water level is lower.

• At those places, a low tide occurs.

• At most beaches, there are high tides and low tides every day. The tides make a cycle.









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Unit 8 Lesson 1 How Do Earth and the Moon Move? · •The part of Earth that points away from the sun gets less sunlight. The part with the least direct sunlight experiences winter