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M20 (NGC 6514, LBN 27, SH2-30, Barnard 85), Trifid Nebula - starforming emission and reflection nebula, with open star cluster, in Sagittarius

LRGB combination (Click for a larger view 1800 x 1800 px)

Details

M20 (NGC 6514, LBN 27, SH2-30, Barnard 85), Trifid Nebula - starforming emission and reflection nebula, with open star cluster, in Sagittarius

Discovered by Charles Messier in 1764.

The Trifid Nebula Messier 20 (M20, NGC 6514) in Sagittarius is a remarkable and beautiful object as it consists of both a conspicuous emission nebula and a remarkable reflection nebula component. The Trifid Nebula M20 is famous for its three-lobed appearance. The name 'Trifid' was first used by John Herschel to describe this nebula. The dark nebula, which is the reason for the Trifid's appearance, was cataloged by Barnard as Barnard 85 (B 85). The red emission nebula with its young star cluster near its center is surrounded by a blue reflection nebula which is particularly conspicuous to the northern end. The nebula's distance is rather uncertain, with values between 2 200 light years (Mallas/Kreimer; Glyn Jones has 2 300) and about 7 600 light years (C.R. O'Dell 1963). The Sky Catalog 2000 gives 5 200 light years, a value which is also used by Archinal and Hynes (2003). The WEBDA database has 3140, the Hubble Press Release of Jeff Hester (STScI-PRC99-42) gives "about 9000" light years.

North is up. The Horizontal FOV is about 32'. The image almost centered at:

Right Ascension 18 : 02.6 (h:m)
Declination -23 : 02 (deg:m)
Distance 5.2 (kly)
Brightness 9.0 (mag)
Apparent Dimension

28 (arc min)

Seeing: Pickering 7 rating - Good
Optic(s): RC 12" with Astro-Physics corrector @ f/5.4
Mount: ASA DDM85 Premium
Camera: ATIK 4000 - monochrome CCD – 2048 x 2048 px ; 16x16 mm; 7.4 µm x 7.4 µm
Filters: Astronomics L, R, G, B set, SupaSlim TrueTechnology Computerized Filter Wheel
Dates/Times: 2012-07-22
Location: Rozhen Observatory, BG, longitude: E 24 44' 18", latitude: N 41 41' 42"
Exposure Details:

L = 30 min, R = 30 min, G = 30 min, B = 30 min, (Bin 1), Subexposures = 10 min, Total Exposure Time - 120 min

More details: Dark and flat frames reduction
Guiding: All subexposures are unguided thanks to ASA DDM85 Premium mount
Processing:

PixInsight / PS

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All Contents copyright Velimir Popov unless otherwise noted.