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Question
A small, dense star the size of Earth that shines by only stored heat is a ________.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.
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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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How did Herschel try to map our Galaxy 200 years ago, and why did he fail?
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Virtually the entire disk of the Galaxy has been mapped using the ________ wavelength.