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Question
In Hubble's "tuning fork," spirals are on the parallel branches.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?
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B) Their energy appears to be non-stellar synchrotron radiation.
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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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