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Question
A region of ionized gas and dust, with imbedded hot young stars, is an ________.Answer
This answer is hidden. It contains 14 characters.
Related questions
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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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