A vast dark cloud of matter in the constellation of
Orion, and in fact invisibly occupying much of that
constellation. The Cloud, which is about 1,300
light years from Earth, is the largest such
phenomenon known in our Galaxy. Occasionally, local events have rendered some portions of
the dark Cloud visible. For example, the formation of the Trapezium system illuminates a
region commonly known as the Orion Nebula.
This infrared image of Orion makes the two connected lobes of the Orion Molecular Cloud easily visible. The southern lobe combines two clouds, designated the Orion A Cloud and the Orion B Cloud, and contains the Orion Nebula (which appears here as a bright patch on the southwestern rim). The circular northern formation is a part of the same complex associated with the starMeissa or Lambda Orionis, and known as the Lambda Orionis Ring. Imagery provided by Aladin sky atlas