AAO image reference AAT 38a. « Previous || Next »
Top left is NE. Image width is about 58 arc min
Image and text © 1999-2002, Anglo-Australian Observatory, photograph by David Malin.
These two star-formation regions appear side by side in the sky and seem to be linked as parts of an extensive nebula. However, the apparent intimacy is 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 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'. The wider field shows the calibration step wedges that provide photometric and colour balance information.
Entry from NGC 2000.0 (R.W. Sinnott, Ed.) © Sky Publishing Corporation, 1988:
NGC 3576 Nb 11 11.8 -61 23 d Car 20.F, lE, 1st of 6 NGC 3579 Nb 11 11.9 -61 14 d Car F, lE, sbM, 2nd of 6 NGC 3581 Nb 11 12.1 -61 18 r Car *12 with fan-shaped neb att, 3rd of 6 NGC 3582 Nb 11 12.3 -61 16 r Car B, bM*, 4th of 6 NGC 3584 Nb 11 12.4 -61 12 r Car F, L, E 0deg , bM, 5th of 6 NGC 3586 Nb 11 12.6 -61 21 r Car eF, S, E 160deg +/- , 6th of 6 NGC 3603 C+N 11 15.1 -61 15 s Car 12. 9.1 glob. cl. and neb, st 15...18
Related Images
AAT 38. NGC 3576 and NGC 3603
AAT 39. The loops of NGC 3576
AAT 40. Reddened nebulosity in NGC 3603
For details of photographic exposure, search technical table by AAT reference number