The Tulip Nebula... Sh2-101
and Black Hole Cygnus X-1
(Click on Picture for larger view)

Added August 4, 2022 ...
This nebula takes the name as it is shaped like that of a tulip in bloom. It is an emission nebula about 6,000 light-years away. It is in the constellation of Cygnus (The Swan). It lies within the Orion arm of the Milky Way.

I took these images using the Orion EON 130mm Triplet Refractor with a monochrome camera and narrow band filters (H-alpha, Sullfur2, and Oxygen 3).I combined the images into different color palettes with one being the famous "Hubble Palette" of SHO (Sulfur, Hydrogen, Oxygen), another at HOO, and a third one using a blend of the SHO and one called the ForaxX Palette.

HOO Palette

ForaxX Palette

ForaxX / SHO Palette

Cygnus X1

Within this view (to the lower right of the 'Tulip') is a hot supergiant star HD 226868 which is associated with an unseen compact black hole, Cygnus X-1. The two orbit about their common center of gravity with a period of 5.6 days. This is perhaps the closest black hole to earth being about 6,100 light-years away. A bowshock is created by a jet of energetic particles from the black hole as they interact with the interstellar medium. It can be seen as a bluish arc at the upper right of the HD 226868.

In the narrowband, the Sulfur 2 filter is sensitive to the upper end of the red light, the Hydrogen Alpha is sensitive in the lower end of the red light, and the Oxygen 3 is sensitive to the lower end of the green into the blue light.

Sulfur 2 channel
upper red spectrum

Hydrogen Alpha channel
lower red spectrum

Oxygen 3 channel
Lower green into blue spectrum

Telescope: Orion EON 130mm Triplet Refractor
Mount: SkyWatcheer EQ6-R Pro
Camera: ZWO ASI 1600 mono cooled to -10°C
Filters: Ha: Baader 3nm, O3: Baader 4nm, S2: ATIK 6nm
- Ha: 18 x 7mn, S2: 17 x 7mn, O3: 18 x 7mn (Total: 6hr 11mn)
Calibration Frames: Flats, Dark-Flats, Darks ... 20 ea Mount: Celestron CGEM
Capture software: N.I.N.A., CPWI, PHD2
Stacking: Deep SkyStacker
Image Combination in PixInsight
Post-Processed in Photoshop

The formula for ForaxX Palette in PixInsight using PixelMath:
// R:
(O3^O3)*S2 + ~(O3^~O3)*Ha
// G:
((O3*Ha)^~(O3*Ha))*Ha + ~((O3*Ha)^~(O3*Ha))*O3
// B:

Return to Pat Prokop's Heavenly Backyard Astronomy Page