by Anthony Ayiomamitis
The large but dim emission nebula Sh 2-132 in Cepheus lies 10,370 light-years away and spans another 272 light-years across. The star at the center of the image below is the very luminous SAO 34301 (HD 211853, mag 8.99), perhaps more commonly known as WR 153, which along with another O-type star (mag 8.5) are primarily responsible for the excitation and ionization of the hydrogen gas in the area and which represents a relatively rare example of a Wolf-Rayet nebula. Harten et al found no evidence of recent star formation but a variable ionization across various parts of the nebula (particularly the brighter portion). The open cluster Berkley 94 (mag 8.7 with an apparent diameter of 4') is visible at the bottom left quadrant below the bright orange star SAO 34387 (mag 6.44) and embedded within the rich nebulosity of Sh2-132.
Technical Details:
Date: July 30-31, 2010 @ 22:25 - 04:25 UT+3
Location: Athens, Greece (38.2997° N, 23.7430° E)
Equipment: Takahashi FSQ-106/f5, AP 1200GTO GEM, SBIG ST-10XME, SBIG CFW10, Baader 7 nm Ha, SBIG LRGB filters
Integrations: HaRGB @ 240:30:30:30 using 6-/20-min subs, 1x1 binning, 2.65"/pixel, -12.5d C
Further details are available here.