The Tulip nebula or SH2-101 lies in the constellation of Cygnus, about 6,000 light years from Earth. As the Tulip nebula was relatively small in the fov of the StellaMira 90mm refractor, I positioned it to the right of center in the field of view so I could include some the interesting adjacent nebulosity.
Although OIII is fairly restricted to the very central portion of the Tulip, I dedicated 20 hours (almost half) of the imaging time to show the bow shock arc just to the right of the tulip and best demonstrated in the OIII (but also seen in the Ha and SII more faintly). . This bow shock is said to be produced by relativistic jets emitted from Cygnus X-1 colliding with the interstellar medium. Cygnus X-1 is an X-ray source and the first such source to be widely accepted as a black hole.
This black hole part of a binary system that includes HD 226868.
HD226868 is a blue supergiant that was noted to show motion with an orbital period of 5.6 days around an 'invisible' companion that was a strong source of Xrays and this X ray emitting object turned out to be the black hole Cygnus X-1.
After collecting abut 10hrs of OIII, I did a test stack and noticed that bow shock wave appeared to be form almost a complete 'egg-shaped' structure so I collected another 10hrs to see if this indeed correct. As the base of the egg shaped OIII structure doesn't envelope HD226868 and Cygnus X-1, I presume this is coincidental OIII being picked up giving the illusion of a complete bubble.
OIII stack
Starless OIII after BlurX and STarX only
Comments