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Question
The age of the whole Galaxy has been found from studies of its oldest stars in the ________ clusters that orbit in the Halo.Answer
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Related questions
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A galaxy with a blueshift is moving ________ Earth.
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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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In active galaxies, their central engines may be temporarily fed by
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Describe the cycle of life and death we observe in the spiral arms.
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Compare the way an optical and radio astronomer would map the Galaxy.
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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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Counting only the material between us and the galactic Center, we measure a mass of ________ billion Suns.
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The ________ is the spherical outer portion of the Galaxy, including the orbits of the globular clusters and most dark matter.
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Virtually the entire disk of the Galaxy has been mapped using the ________ wavelength.