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Question
The initial rise off the main sequence in stage 8 comes from gravitational energy of the contracting helium core.Answer
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Related questions
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Quasar is short for what? Is this true of all of them?
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A galaxy with a blueshift is moving ________ Earth.
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The spiral arms are blue from the presence of Population ________ stars in them.
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When mass is accreted into a black hole, what fraction of the total mass-energy can be radiated away?
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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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How did Herschel try to map our Galaxy 200 years ago, and why did he fail?
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