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Question
Our Sun will fade in luminosity as its supply of hydrogen drops in a billion years.Answer
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Related questions
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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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In active galaxies, their central engines may be temporarily fed by
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