1. Unit 2 Lesson 1 How Does Earth Rotate and Revolve in Space?
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2. Unit 2 Lesson 1 How Does Earth Rotate and Revolve in Space?
Florida Benchmarks
SC.4.E.5.1 Observe that the patterns of stars in the sky stay the same although they appear to shift across the sky nightly, and different stars can be seen in different seasons.
SC.4.E.5.3 Recognize that Earth revolves around the Sun in a year and rotates on its axis in a 24-hour day.
SC.4.E.5.4 Relate that the rotation of Earth (day and night) and apparent movements of the Sun, Moon, and stars are connected.
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3. Day and Night The Earth rotates, or spins.
Unit 2 Lesson 1 How Does Earth Rotate and Revolve in Space?
Day and Night
The Earth rotates, or spins.
This spinning causes day and night.
Earth rotates from west to east once about every 24 hours.
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4. Unit 2 Lesson 1 How Does Earth Rotate and Revolve in Space?
Day and Night
An imaginary pole that runs through Earth’s center is called Earth’s axis.
It runs through the center of Earth from the North Pole to the South Pole.
Earth rotates on its axis.
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5. Unit 2 Lesson 1 How Does Earth Rotate and Revolve in Space?
Day and Night
As Earth rotates, one side of Earth faces the sun. This side of Earth has daytime.
The other side of Earth faces away from the sun. That side of Earth has nighttime.
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6. Seasons Earth revolves around the sun in a path called an orbit.
Unit 2 Lesson 1 How Does Earth Rotate and Revolve in Space?
Seasons
Earth revolves around the sun in a path called an orbit.
Earth takes about 365 days to make one orbit around the sun.
Earth’s axis is tilted to one side. The tilt of Earth’s axis and its orbit cause the seasons.
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7. Seasons Earth is divided into halves called hemispheres.
Unit 2 Lesson 1 How Does Earth Rotate and Revolve in Space?
Seasons
Earth is divided into halves called hemispheres.
The upper half is the Northern Hemisphere. The lower half is the Southern Hemisphere.
The seasons are opposite in the Northern and Southern hemispheres.
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8. Unit 2 Lesson 1 How Does Earth Rotate and Revolve in Space?
Seasons
When one hemisphere is tilted toward the sun, that hemisphere has spring or summer.
When a hemisphere tilts away from the sun, that hemisphere has fall or winter.
As Earth orbits the sun, the two hemispheres are tilted toward and away from the sun.
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9. Unit 2 Lesson 1 How Does Earth Rotate and Revolve in Space?
Patterns in the Sky
A constellation is a group of stars that seems to form a pattern in the night sky.
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10. Unit 2 Lesson 1 How Does Earth Rotate and Revolve in Space?
Patterns in the Sky
The early Greeks named constellations after animals or people from myths.
The Big Dipper is part of a constellation called Ursa Major, or Great Bear.
Orion is a constellation named after a hunter in a Greek myth.
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11. Unit 2 Lesson 1 How Does Earth Rotate and Revolve in Space?
Patterns in the Sky
Constellations seem to move across the night sky as Earth rotates on its axis.
Stars above the North Pole seem to move in a circle.
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12. Unit 2 Lesson 1 How Does Earth Rotate and Revolve in Space?
Patterns in the Sky
The positions of the constellations seem to change with the seasons.
This is because we see different parts of space as Earth revolves around the sun.
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