Question

"What makes us think that the star system Cygnus X-1 contains a black hole?

a) It emits X rays characteristic of an accretion disk, but the unseen star in the system is too massive to be a neutron star.
b) No light is emitted from this star system, so it must contain a black hole.
c) The fact that we see strong X-ray emission tells us that the system must contain a black hole.
d) Cygnus X-1 is a powerful X-ray burster, so it must contain a black hole."

Answer 1

The star system Cygnus X-1 is believed to contain a black hole based on the X-ray emissions from an accretion disk and the high mass of the invisible star in the system.

Step-by-step explanation:

The star system Cygnus X-1 is believed to contain a black hole based on several pieces of evidence. First, it emits X-rays characteristic of an accretion disk, which is a feature commonly associated with black holes. Second, the unseen star in the system has a mass that is too large to be a neutron star, ruling out other possible explanations. Third, the strong X-ray emission observed in the system suggests the presence of a black hole. Therefore, the combination of these factors leads scientists to believe that Cygnus X-1 contains a black hole.