Last Updated：2025/12/03
Cygnus X-1 was the first black hole to be widely accepted by astronomers and belongs to a high-mass X-ray binary with a blue supergiant companion, HD 226868.
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Cygnus X-1 was the first black hole to be widely accepted by astronomers and belongs to a high-mass X-ray binary with a blue supergiant companion, HD 226868.
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