Lesson 1: The Earth-Sun-Moon System

Luis created a clay model of Earth. To show how Earth rotates, Luis wants to use a toothpick to represent Earth’s axis of rotation. Where should Luis place the toothpick?

Choose the correct answer.

• horizontally through Earth in the direction of Earth’s orbit

• vertically through the center of Earth, slightly to the side of each pole

• diagonally across Earth, halfway between the equator and the two poles

• horizontally through Earth from one side of the equator to the other side

Each lunar cycle has one full moon, in which the relative positions of Earth, the sun, and the moon form in a straight line. Which list represents the position of Earth, the sun, and the moon during a full moon?

Choose the correct answer.

• Earth, sun, moon

• sun, moon, Earth

• moon, sun, Earth

• sun, Earth, moon

Oksana observed the appearance of the moon every week for a month. She sketched her observations. Which diagram best shows how the moon’s appearance could have changed during the month Oksana performed her investigation?

Choose the correct answer

• 
• 
• 
• 

What would happen if the time it took for Earth to make one rotation around its axis increased?

Choose the correct answer.

• A day would be shorter.

• A day would be longer.

• A year would be shorter.

• A year would be longer.

A diagram of Earth’s orbit is shown.

Which phrase best defines the orbit of Earth?

Choose the correct answer.

• the position in space of Earth at a certain time

• the distance from the sun to Earth at any point

• the spin of Earth on its axis as it moves forward

• the path Earth travels as it revolves around the sun

Sometimes the moon looks like a crescent. At other times, the moon looks like a half circle. What makes it possible to see the surface of the moon from Earth?

Choose the correct answer.

• The moon gives off its own light.

• Light from Earth is reflected by the moon’s surface.

• Light from the sun is reflected by the moon’s surface.

• The moon absorbs sunlight during the day and glows at night.

In the picture of Earth, the United States is in the center. As Earth rotates, the position of the United States in this picture moves. How often would the United States be in the same position in this picture again?

Choose the correct answer.

• about every 12 hours

• about every 24 hours

• about every 6 months

• about every 12 months

Explain why the same side of the moon is always facing Earth.

Enter your answer in the space provided.

Explain the difference between a total solar eclipse and an annular eclipse.

Enter your answer in the space provided.

Trevor lives in an area that experiences the penumbra of a solar eclipse. Jen lives in an area that experiences the umbra of the eclipse. Explain the difference between the penumbra and the umbra, and describe the difference in the view of the sun for Trevor and Jen.

Enter your answer in the space provided.