outer space

2. Our Milky Way is a spiral ________ containing billions of stars.
4. A large ________ impact is believed to have contributed to the extinction of the dinosaurs.
8. Proxima Centauri, the nearest star to the Sun, is about 4.2 ________ away.
10. She decided to major in ________ because she was fascinated by the study of the universe.
11. A ________, often called a “dirty snowball,” develops a glowing tail when it nears the Sun.

1. Jupiter is the largest ________ in our solar system.
3. Many science fiction movies explore the idea of intelligent ________ visiting Earth.
5. Earth is the third ________ from the Sun in our ________ system.
6. You can see the rings of Saturn clearly through a powerful ________.
7. The ________ of Earth keeps our atmosphere from floating away into space.
9. The International Space Station ________ Earth about every 90 minutes.
12. ________ is often called the Red Planet due to the iron oxide on its surface.