NGC 7635 (Sh2-162) aka "The Bubble" Bright Nebula in Cassiopeia

Located at: RA 23 hours 20 minutes 40 seconds, Dec +61 degrees 12 minutes 00 seconds

Size: 16' x 6.0' Magnitude: -- Class: HII (ionized) region (Sharpless) 3 3 3

North is up

West to the right


 8" f5 Newtonian reflector


 ST-8XME, self-guided, binned 1x1, temp -15c, camera control MaxIm DL 4.56


 Lumicon Red filter, 970 minutes (97 x 10 minute subs), 10/11/12/13/25/262010, FWHM 2.3-3.6 per CCDStack


 CCDStack 2.14.3930.18957, Photoshop 7.0


 Rolling Roof Observatory, Thousand Oaks, CA 91360 (+34d 13m 29s -118h 52m 20s)


This image is a reshoot of a 09/5/2006 red filtered image ... tried a new set of subs to get more data (than the 190 minute first image), but weather has turned cloudy, see posting what I have for now ... finally added 39 more subs for a total of 970 minutes. This is another of those objects that do better with a narrowband H-alpha filter. See the 14.5" version.

From the NGC / IC Project:

Contemporary Visual Observation(s) for NGC 7635

NGC 7635 = Bubble Nebula = Hb 11 = LBN 548 = Sh 2-162
23 20 45 +61 12.7
V = ~10.5;  Size 15x8

17.5": the "Bubble Nebula" extends mainly north [center 5.5' NE] of the involved 
illuminating mag 8.4 star SAO 20575.  There are suspected dark lanes to the 
north with very faint nebulosity just north of this gap.  The main piece curves 
away from the involved star towards the east but appears brightest at the 
western edge near the bright star.  Only a portion of the rim of the "Bubble" 
was viewed.  The view improved with OIII and UHC filters but not dramatically.  
M52 lies 35' NE.

13" (9/29/84): unusual appearance - surrounds a mag 8 star with a mag 7 star 
nearby to the SW. The nebulosity mostly appears north of the mag 8 star with a 
suspected dark lane to the north of this nebulosity. Very faint nebulosity 
appears close north of this lane. The main section hooks around the involved 
star to the east.

- by Steve Gottlieb