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Question
What made supernova 1987A so useful to study?A) We saw direct evidence of nickel to iron decay in its light curve.
B) Its progenitor had been observed previously.
C) In the Large Magellanic Cloud, we already knew its distance.
D) It occurred after new telescopes, such as Hubble, could observe it very closely.
E) All of the above are correct.
Answer
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