At
the Heart of Orion
From NASA’s Astronomy Picture of the Day
Near
the center of this sharp cosmic portrait,
at the heart of the Orion Nebula,
are four hot, massive stars known as the Trapezium.
Tightly
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 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 would make it the closest known black hole to planet Earth.
Image Credit & Copyright: László Francsics