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Question
Stars of type ________ should last about ten billion years on the main sequence.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?
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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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Why aren't there young stars in the halo?
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What advantage do radio astronomers have over optical ones in mapping the entire Milky Way?
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How did Herschel try to map our Galaxy 200 years ago, and why did he fail?
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