1. 1. As the light source moves away from an observer, describe the wavelength of light to the observer.

2. It gets longer.

3. 2. The ozone layer in the atmosphere acts as a shield. What does it shield Earth from?

4. UV radiation

5. 3. Which illustration best represents the shape of the galaxy that includes the Sun?

7. 4. Which characteristic below most likely accounts for our limited knowledge of galaxies? A. their tiny size B. their magnetic cores C. their inability to produce light D. their distance from Earth

8. their distance from Earth

9. 5. Which galactic object can be described as a system of stars, gases, dust, and other matter that orbits a common center of gravity?

10. galaxy

11. 6. Which statement is the best description of the Milky Way galaxy? A. a collection of gases held together by inertia B. a group of planets revolving around a single star C. a collection of stars and gases with the Sun as its center D. a group of stars, dust, and planets held together by gravity

12. a group of stars, dust, and planets held together by gravity

13. 7. A scientific article about the universe will most likely describe the universe as A. consisting of billions of galaxies. B. being less than two billion years old. C. containing approximately ten planets. D. becoming smaller over time.

14. consisting of billions of galaxies.

15. 8. Which statement best describes the relationship between Earth and the Milky Way Galaxy? A. Earth is billions of light-years away from the Milky Way Galaxy. B. Earth is part of a galaxy that is nearest to the Milky Way Galaxy. C. Earth is located in the Milky Way galaxy but far from the galaxy center. D. Earth is positioned in the center of the Milky Way Galaxy.

16. Earth is located in the Milky Way galaxy but far from the galaxy center.

17. 9. In which structure is the Sun located? A. Milky Way Galaxy B. Andromeda Galaxy C. Cat’s Eye Nebula D. Horseshoe Nebula

18. Milky Way Galaxy

19. 10. How long ago did the universe form according to the Big Bang theory?

20. 13.7 bya

21. 11. What type of galaxy is the Milky Way Galaxy?

22. spiral

23. 12. What galaxy cluster does our galaxy belong to?

24. Local Group

25. 13. Which statement below best describes our galaxy cluster? A. It contains less than 12 galaxies. B. It is the smallest galaxy cluster in the solar system. C. It contains 75 known galaxies and has only 5 planets. D. It contains 28 galaxies.

26. It contains 28 galaxies.

27. 14. Based upon the red shift of galaxies, which statement below best describes the movement of galaxies in the universe? A. The galaxies are moving away from our galaxy. B. Galaxies are approaching our galaxy at amazing speeds. C. Galaxies have stopped moving. D. Galaxies are changing colors as they approach our galaxy.

28. The galaxies are moving away from our galaxy.

29. 15. A process occurs in a star that converts matter into energy. Which of these describes the process that includes the conversion of matter into energy? A. Atoms split, decreasing the average size of atomic nuclei. B. Atoms fuse, increasing the average size of atomic nuclei. C. Atoms release electrons to form positive ions. D. Atoms acquire electrons to form negative ions.

30. Atoms fuse, increasing the average size of atomic nuclei.

31. A. The Moon is more similar in composition to Earth than the Sun. B. The Moon has a smaller mass than Earth and the Sun. C. The Moon has a higher density than the Sun. D. The Moon is closer to Earth than the Sun. 16. The influence of the Moon on the tides on Earth is greater than that of the Sun. Which best explains this?

32. The Moon is closer to Earth than the Sun.

33. 17. The temperate zones of the United States experience changing of seasons from winter to summer. Which is the reason for this annual change of seasons?

34. the tilt of Earth’s axis

35. 18. A low tide and a high tide occur in the oceans two times each day. Which factor has the greatest affect on the size of the tides?

36. gravitational pull from the Moon

37. 19. When it is summer in the northern hemisphere of Earth, it is winter in the southern hemisphere. Which statement explains this fact? A. The Sun gives off more heat in the summer and less heat in the winter. B. Earth is farther from the Sun in winter and closer to the Sun in summer. C. With more clouds in the winter, less sunlight can reach the surface of Earth. D. Since Earth is tilted on its axis, heat from the Sun gets distributed unequally.

38. Since Earth is tilted on its axis, heat from the Sun gets distributed unequally.

39. 20. At the equator, Earth spins at a rate of about 1670 kilometers per hour. The circumference of Earth at the equator is about 40000 kilometers. About how long does it take Earth to make one complete rotation on its axis at the equator?

40. 24 hours

41. 21. The axis of Earth is tilted at an angle of 23.5° from the vertical position. Which of the following is the main result of this tilt?

42. Earth’s seasons

43. 22. Identify the shape of Earth's revolution around the sun as stated by Kepler's First Law of Motion.

44. ellipse

45. 23. Which motion of Earth causes its shape to be a oblate(flattened) spheroid?

46. rotation

47. 24. As a scientist, I hope to find a star with planets revolving around it. What might indicate that a planet use to determine if a star has planets revolving around it?(Remember, we modeled this outside with a partner.)

48. barycentre

49. 25. The Sun and other stars are powered by nuclear fusion. Which of these statements correctly describes one of the processes that occur during nuclear fusion in stars? A. Four hydrogen nuclei combine to become a helium nucleus, absorbing energy. B. Four helium nuclei combine to become a hydrogen nucleus, releasing energy. C. Four hydrogen nuclei combine to become a helium nucleus, releasing energy.

50. Four hydrogen nuclei combine to become a helium nucleus, releasing energy.