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Question
Explain how the central engine powers an active nucleus or quasar.Answer
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Why is the energy source for active nuclei like Seyferts thought to be compact?
A) The sources appear to be single stars in photos.
B) Their energy appears to be non-stellar synchrotron radiation.
C) The light can vary over short time intervals.
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E) They are all strong radio sources, with assigned frequencies by their sizes.
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In active galaxies, their central engines may be temporarily fed by
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What advantage do radio astronomers have over optical ones in mapping the entire Milky Way?
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