Multiple Choice
What use are 21 cm radio waves to Galactic astronomers?
A) They cut through the dusty cocoons to let us watch star birth.
B) We can reflect them off the core of the Galaxy.
C) Their Doppler shifts let us map the motions and locations of gas in the spiral arms.
D) They bounce off stars like our Sun to let us precisely measure their distances.
E) They pick up the cool, dark matter much better than can optical telescopes.
Correct Answer:
Verified
Correct Answer:
Verified
Q30: What observations suggest the mass of the
Q34: What do the orbits of halo and
Q35: In age, Galactic disk stars are typically
Q36: The spiral structure of the Milky Way
Q37: Between us and the Galactic center, the
Q56: Matter belonging to the Galaxy can be
Q60: The major problem faced by optical astronomers
Q63: What features of the telescopic view of
Q67: Motions of objects near our Galaxy's core
Q78: From Earth,the view of the Milky Way