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Question
What was most surprising about SN1987A?A) The parent star was a blue supergiant, much like Deneb or Rigel.
B) The supernova was luminous enough to see with the naked eye.
C) The supernova was not even in our own Galaxy.
D) It did not produce the flood of neutrinos our models had led us to expect.
E) Its pulsar appeared within weeks of the explosion.
Answer
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