[b]Strottner-Drechsler 163 / PNG 184.4+05.4[/b] This candidate planetary nebula was discovered by our team in August 2022. StDr 163 in the constellation Gemini is without doubt one of the most beautiful objects in the StDr catalogue. The remarkable aspect of this nebula is that we can literally watch the structure expand. The hot star in the centre is surrounded by a constantly growing envelope of ionised oxygen (OIII). Gently, the blue OIII core breaks through the red cocoon of ionised hydrogen (H-alpha). It is not known whether the reddish halo area around the nebula, which resembles two wings, belongs to the object itself, or whether it is interstellar material that is ionised and excited to glow by the potential white dwarf in the centre. [img]https://cdn.astrobin.com/ckeditor-files/20996/2023/f3dcda6d-8391-47c0-b4d2-a7cd513d3b82.gif[/img] This photo was taken in collaboration with our wonderful friends Peter Goodhew from the UK and Sven Eklund from Sweden. As always, both astrophotographers provided us with excellent data. [img]https://cdn.astrobin.com/ckeditor-files/20996/2023/c3173026-c199-4a16-9b1a-9b7ab8f746b0.jpg[/img] When the stars are removed, the structures of StDr 163 are particularly impressive. [img]https://cdn.astrobin.com/ckeditor-files/20996/2023/d7016560-6847-4f31-9edd-bbd30214a409.jpg[/img] The central star of StDr 163 can only be seen at second glance because of its small size and luminosity. However, its surface temperature of several tens of thousands of degrees and the associated hard UV radiation are sufficient to excite the huge gas clouds around the stellar remnant to emit light. * Data collection: Sven Eklund, Peter Goodhew Pre-processing of the data: Sven Eklund, Peter Goodhew Image processing: Marcel Drechsler * Coordinates : 06:17:16.19 +27:46:36.91 (J200) Constellation : Gemini Size : 4 arcmin (minimum) * [b]Data on the central hot star[/b] - WDJ061716.18+274636.77 (GAIA white dwarf candidat) - Hot Subdwarf - Distance : 1329 parsec (+/-315 866) - parallaxe : 0.8 - 1.0 - Magnitude : 18.9182000 - pm RA 1.96 / DEC -2.49 - pWD : 97,4360 %