6. Between the Sun and the orbit of Mercury, it would be quite possible to place a black hole with a mass of up to 4 million solar masses, that is, comparable to the one located in the center of our Galaxy.
7. Passing the event horizon, matter accelerates to the speed of light.
8. These objects do not pose a danger to space travel unless approached too closely.
9. To get a chance to become a black hole at the final stage of its evolution, a star must be at least ten times more massive than the Sun.
10. The monstrous gravity of black holes forms gravitational lenses in space, thanks to which astrophysicists manage to detect them.
