VOCABULARY Complete each sentence using a word from the article. Use the words in bold to help you.

1. We have to p asteroids from entering the Earth's atmosphere.

2 Do we have t

to find a way

to save the planet?

3 Protecting the Earth will i

building more powerful telescopes.

4 Technology is r

changes in the way we live our lives.

for major

5 How do astronauts p for space travel?

6 Is it L on other planets in the future? that we'll discover life

7 NASA isn't r. mission to Mars yet.

for a manned