Multiple Choice
H I clouds can be observed using _____.
A) optical telescopes above the earth's atmosphere
B) 21-cm radiation
C) x-ray radiation
D) infrared radiation
E) ultraviolet radiation
Correct Answer:

Verified
Correct Answer:
Verified
Related Questions
Q37: List the three types of nebulae in
Q38: Why doesn't warm, dense hydrogen emit 21-cm
Q39: What are "forbidden lines"? Briefly describe how
Q40: Stars are born from the interstellar medium,
Q41: Which telescope imaged the center of the
Q43: The interstellar medium is composed of mainly
Q44: Molecules in the interstellar medium emit radiation
Q45: Match the four components of the interstellar
Q46: Observing at a wide range of wavelengths,
Q47: Which mission is mapping the heliosphere's boundary?<br>A)