Unit 3 Week 3

Weekly Concept Discoveries Essential Question What do we know about Earth and its neighbors?

DISCOVER the Universe Look up at the sky. What do you see? Astronomers first learned about Earth and its neighbors by looking up. Today scientists use telescopes, satellites, and manned spaceships to study the universe. They make new discoveries every day about Earth and our solar system. Talk About lt Write words you have learned about our solar system. Talk with a partner about these discoveries.

Vocabulary Use the picture and the sentence to talk with a partner about each word.

Your Turn Pick three words. Then write three questions for your partner to answer.

Genre. Expository Earth and Its Neighbors Galileo studied the sky with a telescope he built. Essential Question What do we know about Earth and its neighbors? Read about how we have learned about space.

If the Sun could talk, it might say, " Look at me! Look at my sunspots! I am so hot! " Without the Sun, Earth would be a cold, dark planet. How do we know this? Thanks to the astronomer, Galileo, we know a lot about the Sun and the rest of our solar system. Telescopes: Looking Up Galileo did not invent the telescope. However, 400 years ago he did build one that was strong enough to study the sky. When Galileo looked into space, he saw the rocky surface of the Moon. When he looked at the Sun, he discovered spots on its fiery surface. The Moon is Earth's closest neighbor.