Multiple Choice
Why is rapid variability (over the course of weeks) a strong argument that quasars are powered by supermassive black holes?
A) Variability shows that black holes grow rapidly.
B) Variability shows that black holes are unstable.
C) Variability allows astronomers to estimate the size of the emitting region.
D) Variability rules out accretion disks as the source.
Correct Answer:
Verified
Correct Answer:
Verified
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