NGC 3576 and NGC 3603 in Carina
Date created: 1984-03-09
Tags: nebula, dust, AAT
These two star-formation regions appear side by side in Carina
and seem to be linked as parts of an extensive nebula. However, the apparent intimacy is a line-of-sight effect because these two objects are at quite different distances from the Sun.
The curious looped nebula NGC 3576 is about 7000 light years from us while its neighbour NGC 3603 is more than twice as far away. That NGC 3603 is the more distant is confirmed by its colour, which is a ruddier red than the pinkish hue of NGC 3576. The change in colour is due to absorption of the blue-light component of the hydrogen-alpha nebulosity by dust particles in the much longer line of sight. This effect is known as interstellar reddening, though it would be better described as 'de-blueing'. It is also seen in the Horsehead nebula
. Photograph made from plates taken in February 1984
Top left is NE. Image width is about 41 arc min.
Credit: David Malin
© Australian Astronomical Observatory