The UniverseBlack Holes |
How dense are black holes? |
Based on Karl Schwarzschild’s formula for the radius of a black hole’s event horizon, the density of a black hole depends very strongly on its mass. A black hole the mass of Earth, for instance, would have more than two hundred trillion trillion times the density of lead. On the other hand, a black hole that is one billion times the mass of the Sun would have an average density much lower than the density of water.