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Question
The optical classification of galaxies was pioneered in the 1930s by ________.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?
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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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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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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.