SH2-276 - Barnard's Loop in the constellation Orion

The constellation Orion features one of the larrgest emission nebaule in the entire sky, SH2-276, or more commonly known as Barnard's loop. Barnard's loop, which was discovered by E.E. Barnard around the year 1900, was likely formed by a series of supernova explosions approximately 3 million years ago. This emission nebula is located about 1600 light years from Earth and measures approximately 300 light years across.

The RGB portion of this image was captured by shooting the constellation with a standard Canon EF 50mm f/1.8 lens. The H-Alpha portion of this image (red emission nebulae) was captured with the same standard Canon EF 50mm f/1.8 lens, but using a Baader 7nm narrowband H-Alpha filter. The grayscale H-Alpha portion of the image was then added as a luminance channel in the original RGB image. Move the mouse over the image to see the combined HaRGB image.

Also visible in his image are M42, the Great Orion nebula and the Horsehead nebula.

Image Specifications:

     •  Instrument:  Canon EF 50mm f/1.8 (h-alpha f1.8, standard f2.8)
     •  Camera:  Canon 20Da
     •  Filters:  Baader H-Alpha 7nm Narrowband Filter
     •  Mount:  Losmandy GM-8 Equatorial
     •  Guiding:  SBIG STV Autoguider with Vixen 400mm Guidescope
     •  Time / Date :  January 8, 2006, 8:30PM EST
     •  Location:  Coyle Field, NJ
     •  Weather:  Clear, 40degF
     •  Primary Exposure :  20 x 5min, ISO 1600, RAW, H-alpha; 10 x 2min, ISO 1600, RAW standard
     •  Calibration Frames:  16 x 5min, ISO 1600, RAW, dark frames; 16 x 2min, ISO 1600, RAW, dark frames
     •  Image Processing :  Images Plus, PixInsightLE, Photoshop CS2