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.
20 " Keller cassegrain in corrected secondary focus at f/9
|Camera||SBIG STL-11000M at -25C, 8-pos STL filter wheel|
|Date||May 03, 2008.|
|Sky Conditions||dark skies, raw FWHM 1.3-1.7" temperature 7 C,|
R:G:B = 30:30:30 minutes (10-minute sub-exposures);
H-alpha 30 min (10-minute sub-exposure);
synthetic luminance used
Maxim DL 4.5;