Multiple Choice
Interstellar dust grains produce
A) Radio emission at a wavelength of 21 cm
B) Interstellar absorption lines in the spectra of distant stars
C) Extinction and reddening of the light from distant stars
D) Ultraviolet radiation responsible for HII regions
Correct Answer:

Verified
Correct Answer:
Verified
Related Questions
Q32: Why has the 21 cm emission line
Q33: The components of the galaxy,from youngest to
Q34: The orbital period of the Sun and
Q35: The ages of galactic components _ as
Q36: Which of the following kinds of objects
Q38: The bluish color of the nebulosity around
Q39: What property of globular clusters made it
Q40: Which of the following is true of
Q41: The distance of the Sun from the
Q42: We cannot see the other side of