Multiple Choice
We detect neutral gas in the interstellar medium by looking for radiation at 21 cm that arises when:
A) an electron moves from the n = 1 to n = 2 state in a hydrogen atom
B) an electron is ionized from a hydrogen atom
C) carbon monoxide (CO) gas is excited by stellar radiation
D) the spin of an electron flips and aligns with the spin of a proton in a hydrogen atom
E) an electron combines with a proton to make a hydrogen atom
Correct Answer:
Verified
Correct Answer:
Verified
Q24: What primarily makes it difficult to observe
Q25: <img src="https://d2lvgg3v3hfg70.cloudfront.net/TB4371/.jpg" alt=" Figure 1 -Use
Q26: The most common types of stars in
Q27: In the interstellar medium, molecules survive only
Q30: Which of the following traits does NOT
Q31: At what wavelength are H II regions
Q32: For an object in hydrostatic equilibrium, if
Q32: The lowest-density gas in the interstellar medium
Q33: Herbig-Haro objects are almost always found in
Q34: In the densest molecular clouds, the