Tags: Star.
Cygnus X-1 (abbreviated Cyg X-1) is a well-known galactic X-ray source and black hole candidate in the constellation Cygnus. It was discovered in 1964 during a rocket flight and is one of the strongest X-ray sources seen from Earth producing a peak X-ray flux density of 2.3×10−23 W m−2 Hz−1 (2.3×103 Jansky). Cygnus X-1 was the first X-ray source widely accepted to be a black hole candidate and it remains among the most studied astronomical objects in its class.
