Universe - Black Holes - Heart Of Darkness

Black holes lurk in the darkness of the universe. They are invisible places where gravity is so strong that nothing can escape and even space and time warp. The Milky Way is teeming with hundreds of millions of black holes. They circle among the stars. And at the center of our galaxy lies a giant, supermassive black hole millions of times heavier than its smaller cousins: Sagittarius A*. The challenge of studying objects that cannot be seen is immense. Only gradually do we begin to understand them. From their birth in the agony of giant stars, they affect the world around them. They feed on nearby gases and stars, becoming even more massive and powerful through mergers.
Some of them are able to create energetic jets powerful enough to shape the galaxy around them. They show us that concepts like space and time, on which our reality is based, are not as fundamental as we thought.