Terry Robison
The Trifid Nebula
Messier 20, or The Trifid Nebula is an unusual combination of dark, reflective, and emission nebula, plus an interesting open cluster of stars. It is located in an H II region in Sagittarius. The distance from out vantage is around 5200 light years away. It’s a little over 21 light years across, and is fairly bright at Magnitude 6.3. This makes it a fairly popular target with amateur astronomers.
I wanted to highlight the fine Ha filaments that surround this popular target. Ha areas are typically red in astronomical photos. The central area is bright, and tends to have a more washed out colour. On closer inspection, there is a terrific amount of detail running through the lobs. It looks like there are many dark cavernous channels intersecting this area. Each branching out into tiny filaments.
Exposure Details:
Lum 46X900
Red 12X900
Green 8X900
Blue 11X900
Ha 18X1800 8
Total time 28.25 hours
Instruments Used:
10 Inch RCOS fl 9.1
Astro Physics AP-900 Mount
SBIG STL 11000m
FLI Filter Wheel
Astrodon Lum, Red, Green, Blue Filters
Baader Planetarium H-alpha 7nm Narrowband-Filter
Software Used
CCDStack (calibration, alignment, data rejection, stacking)
Photoshop CS 6 (Image processing)
The Trifid Nebula
Messier 20, or The Trifid Nebula is an unusual combination of dark, reflective, and emission nebula, plus an interesting open cluster of stars. It is located in an H II region in Sagittarius. The distance from out vantage is around 5200 light years away. It’s a little over 21 light years across, and is fairly bright at Magnitude 6.3. This makes it a fairly popular target with amateur astronomers.
I wanted to highlight the fine Ha filaments that surround this popular target. Ha areas are typically red in astronomical photos. The central area is bright, and tends to have a more washed out colour. On closer inspection, there is a terrific amount of detail running through the lobs. It looks like there are many dark cavernous channels intersecting this area. Each branching out into tiny filaments.
Exposure Details:
Lum 46X900
Red 12X900
Green 8X900
Blue 11X900
Ha 18X1800 8
Total time 28.25 hours
Instruments Used:
10 Inch RCOS fl 9.1
Astro Physics AP-900 Mount
SBIG STL 11000m
FLI Filter Wheel
Astrodon Lum, Red, Green, Blue Filters
Baader Planetarium H-alpha 7nm Narrowband-Filter
Software Used
CCDStack (calibration, alignment, data rejection, stacking)
Photoshop CS 6 (Image processing)