Sharpless 101 (Sh2-101) is a H II region[1] emission nebula located in the constellation Cygnus. It is sometimes also called the Tulip Nebula because it appears to resemble the outline of a tulip when imaged photographically. It was catalogued by astronomer Stewart Sharpless in his 1959 catalog of nebulae. It lies at a distance of about 6,000 light-years (5.7×1016 km; 3.5×1016 mi) from Earth.
Sh2-101, at least in the field seen from Earth, is in close proximity to microquasar Cygnus X-1, site of one of the first suspected black holes. Cygnus X-1 is located just out of the field of view of the photo in the infobox. The companion star of Cygnus X-1 is a spectral class O9.7 Iab supergiant with a mass of 21 solar masses and 20 times the radius of the Sun. The period of the binary system is 5.8 days and the pair is separated by 0.2 astronomical units. The black hole has a mass of 15 solar masses and a Schwarzschild radius of 45 km. 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 an arc at the top of the photo on the left.
Technical card of image
Imaging telescopes or lenses: William Optics 81GT IV
Mounts: Celestron Advanced VX Goto GEM Celestron AVX
Guiding telescopes or lenses: William Optics RedCat 51 Petzval APO Redcat 51
Guiding cameras: ZWO ASI122mc ZWO
Software: Adobe Photoshop 2021 · PixInsight 1.8 Ripley PinInsight 1.8.8
Filters: ZWO SII 7nm 2″ · ZWO OIII 7nm 2″ · ZWO H-alpha 7nm 2″
Dates:Sept. 21, 2021
Frames:
ZWO H-alpha 7nm 2″: 33×300″ (2h 45′) (gain: 150.00) -15C bin 1×1
ZWO OIII 7nm 2″: 21×300″ (1h 45′) (gain: 150.00) -15C bin 1×1
ZWO SII 7nm 2″: 22×300″ (1h 50′) (gain: 150.00) -15C bin 1×1
Integration: 6h 20′
Darks: 25
Flats: 23
Bias: 50
Avg. Moon age: 15.25 days
Avg. Moon phase: 99.73%
RA center: 20h06m24s.576
DEC center: +35°53′44″.74
Pixel scale: 2.016 arcsec/pixel
Orientation: 2.485 degrees
Field radius: 1.788 degrees
WCS transformation: thin plate spline
More info:Open
| Observation data: J2000.0 epoch | |
|---|---|
| Right ascension | 20h 00m 29.37s |
| Declination | 35° 19′ 13.9″ |
| Distance | 6,000 ly (1,800 pc) |
| Apparent magnitude (V) | 9.0 |
| Apparent dimensions (V) | 16‘ x 9‘ |
| Constellation | Cygnus |
| Designations | Sharpless 101, Sh2-101, Cygnus Star Cloud |
