Center of the emission Nebula NGC 6357

 

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About this Image

This image shows the center part of a well known nebula in the tail of Scorpius. Together with the Cats Paw Nebula NGC 6334 the companion NGC 6357 are both very complex H-alpha emission areas. NGC 6357 is forming some of the most massive stars ever discovered. NGC 6357 houses the open star cluster Pismis 24 (below the bright center of the image), home to these tremendously bright and blue stars. The distance to this nebula is approx. 5500 light years. It is the nursery for many hot young stars, that are still obscured by dust clouds.
North is up.
Find a wide view of this area showing NGC6334 and NGC6357 here.
Find a detailed view of this nebula by R. Gendler and M. Pugh here: 1.
Find a Hubble image of the center part here: 2.


Technical Details
Optics

20 " Keller cassegrain in corrected secondary focus at f/9

Mount Liebscher GEM
Camera SBIG STL-11000M at -25C, 8-pos STL filter wheel
Filters Baader RGB
Date May 03, 2008.
Location IAS/Hakos Namibia
Sky Conditions dark skies, raw FWHM 1.3-1.7" temperature 7 C,
Exposure R:G:B = 30:30:30 minutes (10-minute sub-exposures);
H-alpha 30 min (10-minute sub-exposure);
synthetic luminance used
Programs used Maxim DL 4.5;
CCDStack;
Fitsliberator2;
Photoshop CS3