open cluster of stars in the centre of orion nebular
The Orion Nebula contains a very young open cluster, known as the Trapezium
Orion Nebula
The Orion Nebula contains a very young open cluster, known as the Trapezium due to the asterism of its primary four stars.
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Orion Nebula [SEP] Physical characteristics
The Nebula is visible with the naked eye even from areas affected by some light pollution. It is seen as the middle "star" in the "sword" of Orion, which are the three stars located south of Orion's Belt. The star appears fuzzy to sharp-eyed observers, and the nebulosity is obvious through binoculars or a small telescope. The peak surface brightness of the central region is about 17 Mag/arcsec (about 14 milli nits) and the outer bluish glow has a peak surface brightness of 21.3 Mag/arcsec (about 0.27 millinits). (In the photos shown here the brightness, or luminance, is enhanced by a large factor.) The Orion Nebula contains a very young open cluster, known as the Trapezium due to the asterism of its primary four stars.