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Question
When we see a doubling of the image of single quasar, the body creating the gravity lens is just a brown dwarf close to us.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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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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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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