What would happen if our sun was replaced by a black hole?

Some black holes form after a very large star uses up all its fuel and blows off its outer parts in a gigantic explosion (called a supernova). Then, what is left collapses under the weight of its own gravity to become a super-dense object called a black hole. Our Sun is actually too small to end up as a black hole. read more

If it is replaced by a same mass black hole nothing would change, however, if we replaced it with a same sized black hole means that the event horizon radius is the same radius of the sun and a black hole with such a radius it's mass is about 460000 solar masses (4600000 times mass of the sun) so the gravitational pull of the planets would be tremendous, I wouldn't assume that we would survive such a change in gravity. read more

Our Sun is actually too small to end up as a black hole. It simply does not contain enough matter to exert that kind of gravitational force on itself. A star has to be more than about 10 times the mass of our Sun to become a black hole. read more

Imagine an advanced civilization living on a planet orbiting at a distance of 10 AU (1.5 billion kilometers) from a close binary star system that consists of a 15 MSun red giant star and a 10 MSun black hole. The black hole is surrounded by an accretion disk. read more