The black hole of the Milky Way

Japanese astronomers has discovered that the black hole in the center of our galaxy unleashed a powerful blast for three centuries, thanks to observations with the ESA observatory XMM-Newton and other X-ray satellites and NASA Japanese.  This discovery helps solve a longstanding mystery: why the black hole of the Milky Way is so inactive.  This black hole, known as Sagittarius A-star (A *), is truly massive, contains about four million times the mass of our Sun, the energy radiated from its surroundings is billions of times weaker than the emitted from central black holes in other galaxies.