Exposure: Exposure: Ha - 84 x 4 min (gain-140 1x1), OIII - 84 x 4 min (gain-140 1x1),  RGB - 40 x 2 min (gain-101 1x1) each RGB exposures.

Processing: Data Collection -  N.I.N.A. Sequencer (as FITs).  Sub-frame calibration - Pixinsight (WBPP). Sub-frame  registration and integration (Average combine -  Winsorized sigma clipping) - PixInsight (WBPP).  Mure Denoise - PixInsight. Non-linear stretching, normalization and gradient removal - PixInsight. Photometric RGB calibration (SPCC) - PixInsight. Deconvolution of Ha, OIII, and RGB- BlurXTerminator. Generation of starless nebulosity Ha and OIII  images for later processing - Star XTerminator.  Curves, Levels, RGB combine, Range Compression - PixInsight.  RGB Stars and starless  combine - PixInsight.   Final finishing  - Affinity Photo.   Annotation - PixInsight, Aladin (Simbad and NED), and Affinity Photo. This image is a  modified HOO Narrow Band starless composition - with RGB stars added.  Image processed at 6248x4176 resolution. Final Image size is approximately  6159x4087.

North is up in this image.  This image shows the supernova remnant CTB1 (also known as Abell 85).  This  structure and surrounding region has  emission line nebulosity.  In addition , LBN 576 is related to CTB1 and is historically identified as the bright lower rim of the supernova. This structure is approximately 9,780 to 10.000 light years distant. Also prominent in this image is a number of open clusters. - most are in the Milky Way Star Cluster catalog. Notable clusters are King 12 and King 21. The small red structure to the right of CTB1 is a candidate planetary nebula known as PN WE 2-262.     These objects and some of the brighter stars are identified in the annotated image.  This image replaces an earlier image of this region and can be seen in the Archives here.  Horizontal FOV is approximately 150 arc minutes. Full size image scale is about 1.47 arcsec/pix.

Image center is approximately - Equatorial 2000: RA: 23h 59m 18s Dec: +62°25'32"