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Question
Describe the changes in the Sun from beginning to end of a sunspot cycle.Answer
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Related questions
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Describe the reasoning leading to the idea that the number of technological civilizations in the galaxy is equal to the average lifetime of a technological civilization.
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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.
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In active galaxies, their central engines may be temporarily fed by
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Describe the cycle of life and death we observe in the spiral arms.
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What advantage do radio astronomers have over optical ones in mapping the entire Milky Way?
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