DWB 111 The Propeller Nebula

Click here for a full resolution image of only the Propeller itself

The Details
Object	DWB 111 The Propeller Nebula in Cygnus
Optics	Takahashi FCT-76 at f/4.5
Platform	Astro-Physics 1200 GTO
Camera	SBIG ST-10XME
Filters	Custom Scientific 3nm Hydrogen-Alpha
Date	22 July 2005
Location	Mount Wilson Observatory - Mount Wilson, CA
Exposure	Ha 9 x 1200 sec, 1x1 bin
Software	Maxim DL/CCD, Registar, Photoshop CS
Orientation	Field of View: 02°27’ x 01°39’ centered on RA 20h17m56.9s DEC +44°09’20” (2000.0) . North angle 272.5°; east 90° CCW from north.
Notes	DWB 111 (aka MRSL 479), part of a much larger association of ionized hydrogen gas, is also known as the Propeller Nebula. Looking in the upper right quadrant of the above image, the Propeller can be seen forming a bright S-shaped curve. The DWB catalog is a somewhat lesser-known document developed by H. R. Dickel, H. Wendker and J. H. Bieritz cataloging 193 distinct objects as part of their study of H-alpha emission nebula in the Cygnus X region of the sky. The MRSL Comparison Catalog of H-II Regions, authored by Pavla Marsalkova of the Stefanik Observatory, Prague, Czechoslovakia, is a compendium of a number of other catalogs (Sharpless, DWB, etc..) that includes 698 objects of interest. Research of these catalogs can yield some very rewarding and otherwise little known targets for amateur astronomers interested in the H-alpha imaging format.