Universe/Galaxies

3. Scientists think that _____ may be the only planet in our solar systerm with the right conditions to support life.
4. Some high-mass stars become ____.
7. In 1953, who carried out the first such experiement?(one of them)
8. Scientists who study cosmology are called ____.
10. Which theory did the scientists use to describe the beggining of the universe?
11. After a high-mass star's energy is used up, they swell up into ____ ____
13. Scientists have found evidence that the ____ of the universe is not constant.
15. In 1987, who discovered a supernova?
16. What is combined to form the proteins that make up living things?
17. The light energy from almost all galaxies shows the ____ ____.

1. People are often willing to believe that othe planets in the universe are _____.
2. The more massive chunks pulled in all the matter in the space around them eventually become the ____.
5. Scientists think that our ____ formed the way all other stars do.
6. Which theory suggests that the universe expands to a maximum size and then contracts?
9. Durring ____ of years, some chunks grew in the size until they were large enough to have a strong gravity.
12. If you observe a galaxy through a _____, you would see a spectrum with lines moved foward the red region.
14. All ____ begin their lives in nebulas, huge clouds of dusts and gases.
18. Planets probable form while a star is ____.