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Question
What three properties describe a black hole?Answer
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Related questions
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The spiral arms are blue from the presence of Population ________ stars in them.
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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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What advantage do radio astronomers have over optical ones in mapping the entire Milky Way?
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