The Witch's Broom



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The Veil Nebula is a cloud of heated and ionized gas and dust in the constellation Cygnus. It constitutes the visible portions of the Cygnus Loop (radio source W78, or Sharpless 103), a large but relatively faint supernova remnant. The source supernova exploded about 3,000 BC to 6,000 BC, and the remnants have since expanded to cover an area roughly 3 degrees in diameter. The distance to the nebula is not precisely known, but data supports a distance of about 1,470 light-years.

The names Veil Nebula, Cirrus Nebula, and Filamentary Nebula generally refer to all the visible structure of the remnant, or even to the entire loop itself. The structure is so large that several NGC numbers were assigned to various arcs of the nebula. There are three main visual components: The Western Veil (also known as Caldwell 34), consisting of NGC 6960 (the 'Witch's Broom', 'Finger of God', or 'Filamentary Nebula') near the foreground star 52 Cygni;
The Eastern Veil (also known as Caldwell 33), whose brightest area is NGC 6992, trailing off farther south into NGC 6995 (together with NGC 6992 also known as 'Network Nebula') and IC 1340;
The Pickering's Triangle (or Pickering's Triangular Wisp), brightest at the north central edge of the loop, but visible in photographs continuing toward the central area of the loop.

NGC 6974 and NGC 6979 are luminous knots in a fainter patch of nebulosity on the northern rim between NGC 6992 and Pickering's Triangle The nebula was discovered on 1784 September 5 by William Herschel. He described the western end of the nebula as 'Extended; passes thro' 52 Cygni... near 2 degree in length', and described the eastern end as 'Branching nebulosity... The following part divides into several streams uniting again towards the south.' [Wiki]

R-Gsynth-B composition:
R = Ha
G = 0.75*OIII + 0.25*Ha
B = OIII

Hubble palette rendition


Optic SW Quattro 8S 200mm f/4 with Baader MPCC Mark III corrector
Camera Atik 383L+
Filters Baader Ha, OIII, 36mm
Mount NEQ6 with EQASCOM
Guide
SW 70/500 with AlCCD5
Frame center
RA:20:46:08 DEC 30:42:50 J2000
Date
19th August 2017
Site
S.Barthelemy, Aosta Valley, Italy
Exposures Ha - 11x600s bin 1x1 @10°C
OIII - 15x600s bin 1x1

Integration time - 4h20m

NGC6960_HOO

NGC6960_HOO

NGC6960_HOO

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