Near the center of this sharp cosmic portrait, at the heart of
the Orion Nebula, are four hot, massive stars Gathered within a
region about 1.5 light-years in radius, they dominate the core
of the dense Orion Nebula Star Cluster. Ultraviolet ionizing
radiation from the Trapezium stars, mostly from the brightest
star 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 recent
dynamical study 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 1500 light-years would make it
the closest known black hole to planet Earth. Image Data -
Hubble Legacy Archive,