Astrophotography by Keith B. Quattrocchi

Sharpless 2-142/NGC 7380
Central Region
Emission Nebula and Open Cluser in Cepheus
Narrow Band Image(Modified)

Copyright 2009
Keith B Quattrocchi

          
Image Acquisition Information                      
 
Telescope: 16" RCOS Richey Chretien Telescope (ion milled at 6/9) 
Camera:  SBIG STL-6303 M
Guiding: SBIG AOL,  Astrodon  MOAG AOG (SBIG 237 with Custom FLR)
Filters: Astrodon Ha, SII, OIII
Mount: Software Bisque Paramount ME
Acquisition Programs:   The Sky,CCDAutopliot III, CCD Soft. 
Processing Programs: CCDStack, Maxim DL, Photoshop
Date: July3, 2009 - July 29, 2009                              
Time: 20 x20 min ( 6.66 hours) each for each of Ha, SII and OIII:
Total of  20 hours imaging time.                              
Processing:  CCD Stack and PhotoShop CS/3
 
Image Infornmation:  Sharpless 2-142 is an emission nebula embedded in the open star cluster NGC 7380, at a distance of about 7200 light years. The emission nebula (Sh2-142) has been noted to be peculiar in shape and "composed of  several bright arcuated clouds, rims and Hα knots interlaced with local dust lanes" ( Chavarria-K, et al).  The nebulosity does have an un usual "scalloped" appearance, as can clearly be seen in this NB image, and it has been called the Clamshell nebula by some (though this name has also been associated with Sh2-119).   This region contains some 4000 solar masses of  gas, primarily hydrogen.  The major ionizing star is an eclipsing binary star DH Cephei).            

Additional Comments:  This Narrow Band image was processed using CCDStack, producing a Narrow Band image (Hubble Palatte).  The Narrow Band image was created by an unequal weighting of SII/Ha/OIII at a ratio of 2:1:5 (OIII signal is relatively weak).   This was layered over a modified (enhanced) H-alpha image to bring out some of the details lost in the assembled narrow band image.   The  Further data stretching, high pass filtering and background smoothing was performed with Adobe Photoshop CS/3.