Black holes cannot be seen because they do not emit visible light or any electromagnetic radiation. Then how do astronomers infer their existence? I think it's now almost established in the scientific community that black holes do exist and certainly, there is a supermassive black hole at the centre of our galaxy. What is the evidence for this?
Black Holes – What Is the Evidence for a Supermassive Black Hole at the Center of the Milky Way?
astronomyastrophysicsblack-holesgalaxiesmilky-way
Best Answer
This is not absolutely correct in the sense that visible light is emitted during the capture of charged matter from the radiation as it is falling into the strong gravitational potential of the black hole, but it is not strong enough to characterize a discovery of a black hole. X rays are also emitted if the acceleration of the charged particles if high, as is expected by a black hole attractive sink.
The suspicion of the existence of a black hole comes from kinematic irregularities in orbits. For example:
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From frequently asked questions, What evidence do we have for the existence of black holes?, first in a Google search:
Again, it is only a black hole that fits these data in our general relativity model of the universe.
So the evidence for our galaxy is based on kinematic behavior of the stars and star systems at the center of our galaxy.