Cygnus X-1
Cygnus X-1 is a source of X-Ray radiation, believed to be a black hole. It is part of a binary system with a star called HDE 226868.
Image by Chandra X-ray Observatory
Credit: NASA/CXC
- One of the strongest X-ray sources seen from Earth.
- Radius of its event horizon is probably about 26 km.
- Orbits a blue supergiant variable star (HDE 226868) at about 0.2 AU.
Names: Cygnus X-1, AG (or AGK2)+35 1910, BD+34 3815, HD (or HDE) 226868, HIP 98298, SAO 69181, V1357 Cyg.
Constellation: Cygnus