Sh2-101 - Tulip Nebula in Hα

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Sharpless 101, located near the right edge of this image, is an emission nebula located in the constellation Cygnus. The emission of the Tulip Nebula is excited by ultraviolet radiation of the hot young star HD 227018 in its center. It somewhat resembles a tulip seen from its side. Sh2-101 lies at a distance between 6,000 and 8,000 light years from Earth. An interesting feature of the Tulip Nebula is its close proximity (from our viewpoint on Earth) to the galactic X-ray source Cygnus X-1, which is one of the strongest X-ray sources known, and widely accepted to be a black hole. It was discovered in 1964.

Sh2-101 - Tulip Nebula and Enironment in Hα, Wright-Newtonian CCD image;
Sh2-101 - Tulip Nebula, which this image is part of.

Exposure Data

Instrument: 242 mm f/4.8 Newtonian with 3.5nm Hα filter
F/stop: 4.7
Exposure: 82 x 10 min
Camera: ZWO ASI1600MM Pro
Date: September 9 - October 9, 2021 (3 nights)
Location: Floridsdorf, Vienna
Conditions: Visual limiting magnitude 4.0-4.5 mag, SQM-L sky brightness 18.7-19.2 mag/arcsec², seeing 1.4-1.7 arcsec, no wind, low to moderate humidity, 6-20°C
Autoguider: Lacerta MGEN
Enhancement: File selection and bias/dark/flat calibration, star alignment and image integration, background flattening, deconvolution, non-linearization, star-background separation, noise reduction, local contrast enhancement, star size reduction, re-adding of the stars