This nebula is a minor nebula in the Sagittarius arm of the Galaxy a few thousand light years from the Eta Carinae nebula. When John Herschel discovered this nebula in 1834 he could only see several bright nebulous patches and eventually this nebula received six separate classification numbers. These days astronomers usually call the entire nebula NGC 3576.

The Nebulae associated with the NGC 3576 nebula

NGC 3576,NGC 3579,NGC 3581,NGC 3582,NGC 3584,NGC 3586,NGC 3603

This is a list of the nebulae in this region. These are the six patches of the nebula which were classified in the nineteenth century. The entire nebula extends across about one degree of the sky and it has a diameter of about 100 light years. Also included in this list is the much more distant NGC 3603 nebula which is in the same area of the sky; this nebula is only the brightest part of an enormous nebulous region which probably extends over 1000 light years of space.

NGC 3576, 3579, 3581, 3582, 3584 and 3586 are all bright patches in the centre of the nebula. To the north of the NGC 3576 region are several star clusters which are probably quite close to the nebula. The region to the left of NGC 3576 is the completely separate NGC 3603 nebula. This nebula is about 14000 light years behind NGC 3576.

NGC 3603 - The largest nebula in the Galaxy?

West of NGC 3576 is a much more distant nebula. Although it is very obscured, the bright central part of this nebula is visible to us. This nebula may be one of the largest nebulae in the entire Galaxy (it is an example of a "giant HII region"). To astronomers in other nearby galaxies it would be a visible as a bright pink spot on the Sagittarius Arm. This picture shows the bright central region of this nebula which contains a very compact and very young cluster of stars.