The Trapezium Cluster (or Orion Trapezium Cluster)
is an open cluster located in the
Orion Nebula, within the constellation, Orion.
It is also known as Theta1 Orionis
aka Theta 1 Orionis, a Bayer designation variant
presumably given the cluster due to a somewhat star-like appearance.
Four relatively bright stars are visible, generally designated
by one of the above cluster names with an A, B, C, or D.