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Question
The formation of carbon requires a core temperature of about 100 million K, but iron takes much higher temperatures and pressures.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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A galaxy with a blueshift is moving ________ Earth.
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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.
C) The light can vary over short time intervals.
D) We know the masses of the black holes that lurk there, and can find their radii.
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In active galaxies, their central engines may be temporarily fed by
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