M20 - The Trifid Nebula in Sagittarius


Copyright 2010 Hap Griffin

This nebula gets its name from the fact that the main cloud is tri-sected by a dark nebula into three main sections.  The beautiful red and blue colors come from the regions of the nebula where hydrogen is glowing (red) and reflecting starlight (blue).  The red portion is excited to emission by the ultraviolet light coming from a triple star system embedded within.  The distance to the Trifid is approximately 5200 light years, although there is a large disparity between various sources.  


Date/Location:    August 7-8, 2010     Griffin/Hunter Observatory    Bethune, SC
Camera: QSI 583wsg
Filters: Astrodon E Series Generation 2 LRGB
CCD Temperature: -10 C
Instrument:    Planewave CDK 12.5"  
Focal Ratio:   f/8
Mount: AP-1200
Guiding:    Auto via the QSI camera's built in Off-Axis Guider mirror and an SBIG ST-402 Guider
Conditions:    Hot and humid, clear for summer in SC
Weather:    85-75 F, still
Exposure: 270 minutes total (12 x 10 minutes Luminance, 5 x 10 minutes each RGB binned 2x2)
Capture: CCDAutopilot 4 w/ Maxim DL Camera Control, focused automatically w/ FocusMax   
Processing:    Frame calibrations, alignment and stacking with ImagesPlus v3.80.  Finishing in Photoshop CS4.  Noise reduction with Noise Ninja.