Explanation: What lies in the heart of Orion? Trapezium: four bright stars, that can be found near the center of this sharp cosmic portrait . Gathered within a region about 1.5 light-years in radius, these stars dominate the core of the dense Orion Nebula Star Cluster. Ultraviolet ionizing radiation from the Trapezium stars , mostly from the brightest star Theta-1 Orionis C powers the complex star forming region's entire visible glow. About three million years old, the Orion Nebula Cluster was even more compact in its younger years and a dynamical study indicates that runaway stellar collisions at an earlier age may have formed a black hole with more than 100 times the mass of the Sun . The presence of a black hole within the cluster could explain the observed high velocities of the Trapezium stars . The Orion Nebula's distance of some 1,500 light-years make it one of the closest candidate black holes to Earth.