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Question
What is Cygnus X-1?A) the brightest star in the constellation Cygnus
B) the leading candidate for an observable black hole binary system
C) the strongest X-ray eclipsing binary system in the sky
D) a millisecond pulsar with three Earth-like planets around it
E) the first gamma-ray burster to be spotted in other wavelengths as well
Answer
This answer is hidden. It contains 1 characters.
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