Chapter 19

The Cosmic Perspective, 7e (Bennett et al.)
Chapter 19 Our Galaxy

19.1 Multiple-Choice Questions

1) What is the diameter of the disk of the Milky Way?
A) 100 light-years
B) 1,000 light-years
C) 10,000 light-years
D) 100,000 light-years
E) 1,000,000 light-years
Answer: D

2) What is the thickness of the disk of the Milky Way?
A) 100 light-years
B) 1,000 light-years
C) 10,000 light-years
D) 100,000 light-years
E) 1,000,000 light-years
Answer: B

3) What kinds of objects lie in the halo of our galaxy?
A) open clusters
B) O and B stars
C) globular clusters
D) gas and dust
E) all of the above
Answer: C

4) What kinds of objects lie in the disk of our galaxy?
A) open clusters
B) O and B stars
C) old K and M stars
D) gas and dust
E) all of the above
Answer: E

5) Which of the following comprise the oldest members of the Milky Way?
A) the Sun and other solar mass stars
B) O stars
C) red giant stars in spiral arms
D) Cepheid variables
E) globular clusters
Answer: E

6) What makes up the interstellar medium?
A) open clusters
B) O and B stars
C) K and M stars
D) gas and dust
E) all of the above
Answer: D
7) If you were to take a voyage across the Milky Way, what kind of material would you spend most of your time in?
A) empty space–a pure vacuum
B) dusty molecular clouds
C) star clusters
D) warm, rarefied clouds of atomic hydrogen
E) cool, dense clouds of atomic hydrogen
Answer: D

8) How does the interstellar medium obscure our view of most of the galaxy?
A) It produces so much visible light that it is opaque and blocks our view of anything beyond it.
B) It reflects most light from far distances of the galaxy away from our line of sight.
C) It absorbs all wavelengths of light.
D) It absorbs visible, ultraviolet, and some infrared light.
E) all of the above
Answer: D

9) How can we see through the interstellar medium?
A) by observing in high-energy wavelengths such as X rays and long wavelengths of light such as