RA: 19h 49m Dec: +26º 52' Mag: 30, Size (ly):9.8, Distance (ly):7,800
LBN 144 (aka: Sharpless 2-90) is an emission nebula located in the constellation Vulpecula. Considered a 'blister' H II region (Zuckerman 1973, Israel 1978) this nebula was created, like so many H II regions, when a new born star forms near the edge within a molecular cloud. Radiation from the star causes the surrounding cosmic matter to rapidly ionize. As the volume of ionized gasses increase and expands, the ionized front reaches the cloud border to break through and flows out at high velocities into the surrounding neutral cloud per the 'Champagne' model effect (Tenorio-Tagle 1979, Bodenheimer et al. 1979). This breakthrough leads to the stars becoming observable in the UV and visible spectrum, exposes the cavity and produces what appears to be a blister on the surface of the molecular cloud. The molecular cloud near LBN 144 has a size of about 60,000 solar mass and lies partly in front of the H II region.
The distinctive 'U' shape cavity of LBN 144 is caused by a dark optical absorption trunk extending from the east into the center. The west/south west areas display ionization fronts. The southern area displays a diffused extension of ionization medium flowing out of the shell area at high velocities. There is some debate as to the identification of the exciting star but it's more likely to be within the center of the shell hidden behind the optical absorbing matter.
|Location & Date||
Backyard, Abbott Observatory - Aug 14,15, 2009
Temperature - Mid 70's F
|Telescope||Deep Sky Instruments RC10C , F/7.3 on a Losmandy G11 Gemini, Prime Focus, Image scale 0.82 arcsec/pixel|
SBIG ST-2000XM w/CFW8, AO8
Astrodon Tru Balance LRGB Filters
CCD temp -15°C
|Exposure Times||(L) 13 X 15, (R) 7x15, (G) 4x15,(B) 9x15 Minutes, Bin 1x1|
Image planning - CCD Navigator
Image acquisition/focus/guiding/dither - CCD Autopilot4 w/CCDSoft/TheSky6/PinPoint
* CCD Stack- Calibration, Normalize, Alignment, Mean Combine, Deconvolution, Mild DDP
* Adobe CS4 - L+RGB combine, Levels, Curves, Sharpening, Cropping, NR, JPEG conversion