vdB 141 The Ghost Nebula

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2014/08/23 - Fifth light of our remote setup. We spent almost 34 hours on this object. Conditions weren't good; bad weather, moon and seeing interfered. So it took us more than a month, 12 sessions, to gather some decent data.

vdB 141 (also known as Sh2-136) is a reflection nebula in the constellation Cepheus. It's located in the western part of the constellation, about one degree to the east of the famous Iris nebula (NGC 7023); the best time for your observation in the evening sky is between the months of July and December.

It's an isolated Bok globule located in the great dark nebulous system that masks the light of the Milky Way in the constellation of Cepheus; its distance is equal to about 450 parsecs (about 1470 light years). The central globule is known by the abbreviation CB 230; it is home to the source of infrared radiation IRAS 21169 + 6804, associated with a young stellar object at the center of a bipolar jet. Together with a nearby source in the visible near-infrared form a pair of protostars that could constitute a binary system. The jet is oriented in a north-south and has a total length of about 0.06 light years.

Object information
Name : vdB 141 The Ghost Nebula
Type : Nebula
Constellation : Cepheus
Distance : 1.470 light-year
Apparent dimensions : 5' x 5'
Apparent magnitude : 9.40

Image information
Image date : 2014/08/23, 2014/08/06, 2014/08/05, 2014/08/04, 2014/07/31, 2014/07/30, 2014/07/28, 2014/07/27, 2014
Right ascension : 21:16:27.044
Declination : 68°12' 2.58"
Focal length : 1687.21 mm
Focal ratio : f/6.64
Image resolution : 0.660 arcsec/pixel
Field of view : 36' 10.6" x 27' 5.3"
Sky quality : 21.50 mag/arcsecond2
Guiding rms : 0.3 arcsec
Sensor temperature : -20°C
Light frames : 33 hours, 45 minutes total exposure time
59x 900 sec. luminance unbinned
13x 1800 sec. red unbinned
13x 1800 sec. green unbinned
12x 1800 sec. blue unbinned
Image acquisition with ACP Observatory Control Software, ACP Scheduler and Maxim DL
Auto-guiding with Maxim DL
Auto-focusing with FocusMax
Bias frames : 100x unbinned
Dark frames : None
Flat frames : 30x luminance unbinned
30x RGB unbinned
Automated sky twilight flats with ACP
Processing : PixInsight for calibration, alignment and integration.
Adobe Photoshop CS6 for final touch.

Equipment information
Telescope : Orion Optics 10" ODK
Corrector : None
Focuser : Baader SteelTrack with SteelDrive
Mount : Mesu Mount 200 with Sidereal Technology SiTech Controller
Camera : QSI 683wsg-8 cooled CCD camera with Kodak KAF-8300 sensor and Off Axis Guide (OAG) port
Guidecamera : Starlight Xpress Lodestar autoguider
Filters : Astrodon Tru-Balance E-Series LRGB & Astrodon 3nm H-α, 3nm O-III, 3nm S-II and 3nm N-II
Observatory site : www.sunstarfrance.com, Hautes-Alpes, France