Question :
31.Which of the following can't be associated with the spiral : 1777259
31.Which of the following can't be associated with the spiral arms of a galaxy?
A.Dust and gas
B.Metal poor stars
C.Young, massive stars
D.Star formation
32.How did Harlow Shapley determine where the center of the galaxy lies?
A.He plotted the distribution of open clusters.
B.He plotted the distribution of globular clusters.
C.He made star counts in every direction of the galactic disk.
D.He measured the amount of dust obscuration in every direction of the galactic disk.
33.How does the traditional theory of the formation of the galaxy explain the origin of globular clusters?
A.They formed in the disk and later were ejected to the halo.
B.They formed in other galaxies and were captured by close interactions.
C.They build over time from the collision of stars in the halo.
D.They formed early on during the free-fall collapse of the proto-galactic material.
34.What behavior do galactic rotation curves exhibit to suggest the existence of dark matter in an extended halo?
A.Small velocities are seen at large distances from the galactic center.
B.Small velocities are seen at distances close to the galactic center.
C.Large velocities are seen at large distances from the galactic center.
D.Large velocities are seen at distances close to the galactic center.
35.How did Harlow Shapley use the period-luminosity relationship of RR Lyrae variables to determine the size of the Milky Way galaxy?
A.He determined the proper motion of globular clusters in the outer disk of the galaxy.
B.He found the distances to individual variables free floating in the halo.
C.He found the distances to open clusters found throughout the disk of the galaxy.
D.He found the distances to globular clusters distributed about the center of the galaxy.
36.If a star with a large peculiar proper motion and/or speed with respect a typical disk star is found what other property would you expect it to have?
A.Low luminosity.
B.Poor metal content compared to the Sun.
C.Old age.
D.All of the above.
37.How is the age of the galaxy determined?
A.Measuring the metallicity of Population II stars.
B.Finding the turnoff point in the H-R diagram of globular clusters.
C.From the motion of stars in the galactic halo.
D.Counting the number of open clusters in the spiral arms.