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Question
The supernova that created the Crab nebula and its pulsar was seen on Earth in the year ________.Answer
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Related questions
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Describe the reasoning leading to the idea that the number of technological civilizations in the galaxy is equal to the average lifetime of a technological civilization.
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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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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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Virtually the entire disk of the Galaxy has been mapped using the ________ wavelength.