Multiple Choice
Interstellar absorption lines are narrow primarily because:
A) there is very little interstellar matter.
B) molecules always produce narrow absorption lines.
C) most of the matter is ionized, and atoms moving fast produce sharp lines.
D) the matter is at a low temperature, and atoms are almost still.
E) All of the above are correct.
Correct Answer:
Verified
Correct Answer:
Verified
Q2: Interstellar gas is composed of:<br>A)only hydrogen.<br>B)90% hydrogen,
Q3: The overall dimming of starlight by interstellar
Q4: The average temperature of the typical dark
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Q6: Explain the colors of emission nebulae.
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Q8: Emission nebulae like M42 occur only near
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Q11: The gas in the interstellar medium consists