Another piece of evidence proving the existence of black holes is the spaghettification effect. You might wonder what this means, but if you ever get a chance to look into a black hole, it will become self-evident: Due to the extremely strong gravitational pull of a black hole, anything will be stretched into long thin strips, like spaghetti. Although this could happen to ordinary matter, if a star gets too close to a black hole, this is its fate. In October 2020, astronomers indeed observed a flash of light when a star was devoured by a black hole. Fortunately, this "tragedy" occurred some 215 million light-years away from us.
The photo of the black hole
The first direct photo of a black hole taken by humans.
