Earth’s
Rotation and
Revolution
Reader’s
Theater
Speaking Parts:
Student
Teacher
Earth
Sun
Moon
Winter
Summer
Spring
Autumn
Earth’s Rotation and Revolution
Reader’s Theater
Student: How does the sun know to go down at the end of the day?
Teacher: Actually, the sun doesn’t move. It’s the Earth that is moving.
Student: Really? I can’t feel us moving.
Teacher: That’s because we are moving smoothly and at the same speed.
Earth: That’s right! I am spinning on my axis.
Student: What is an axis?
Earth: Think of it as an imaginary line that passes through my North and South
Poles. I am constantly spinning on the axis. This is called rotating.
Student: Is that like when I spin in a circle?
Earth: Exactly!
Sun: When the Earth rotates on its axis, half of it is facing the sun and the other
half is facing away from the sun. The half that faces the sun gets light and this
makes the daytime. The other half that is facing away from the sun gets no light.
This is nighttime.
Student: So someone in London might see the sun while someone else in
Honolulu will still be in the dark?
Sun: This is true because of the Earth’s rotation. The spinning makes it look like I
am moving from East to West.
Student: Yes, it looks as though the sun moves in the sky from the right to the
left.
Sun: I always rise in the East and set in the West.
Teacher: It takes 24 hours for the earth to complete one rotation.
Earth: This means I complete one full spin each day.
Sun: Without rotation, one side of the earth would never receive light.
Student: But I thought the moon gave off light. It always looks so bright!
Moon: It may look like I am providing light, but I am really just reflecting the light
from the sun onto the earth. That’s why sometimes only part of me is lit up.
Teacher: That’s the lunar cycle. The moon revolves around the earth in stages.
Student: What does it mean to revolve?
Teacher: Revolve means to circle around something. The moon revolves around
the Earth and the Earth revolves around the sun.
Earth: I am making one an entire circle around the sun every year. It takes me
365 days to do this because it is such a long journey.
Teacher: Do you know what the earth’s revolution causes?
Summer: The seasons! The seasons are caused because of Earth’s axis, that
imaginary line form the North to the South Poles, is a bit tilted.
Spring: It is tilted 23.5° to be exact. This means that the earth is always pointing
to one side as it revolves around the sun.
Autumn: Sometimes the North Pole is pointing toward the Sun and sometimes
it’s not. The different amount of sunlight parts of the earth receives during the
year creates the seasons.
Winter: Let’s think about what happens in the winter. The Northern Hemisphere
is not pointing toward the sun and will have winter because it is not getting as
much heat and light from the sun. This causes longer nights and shorter days.
Spring: As the earth revolves around the sun, the North Pole begins to point
more toward the sun and the northern hemisphere gets a bit more heat and light.
This causes springtime.
Summer: We get summer when the Northern Hemisphere is leaning most
toward the sun. This means more heat and light leading to longer days and
shorter nights.
Autumn: Once the North Pole starts moving away from the Sun, the Northern
Hemisphere starts getting less heat and light. This is the autumn season.
Winter: The Earth eventually complete ones full revolution and we are back to
winter.
Student: So does that mean that people in the Northern Hemisphere have
summer while people in the Southern Hemisphere have winter?
Teacher: That’s right! It’s all because the earth is tilted on its axis!