HFG1, also cataloged as PK 136+05, is a planetary nebula located in the constellation Cassiopeia. This peculiar object stands out due to its fascinating interaction with the interstellar medium, resulting in an intricate and extended structure that captivates astronomers and astrophotographers alike.

HFG1 was first cataloged in 1982 by Heckathorn, Fesen, and Gull (hence the name "HFG"). It surrounds the binary system V664 Cas, consisting of a white dwarf and a companion star. The pair’s movement through space at high velocity creates a spectacular bow shock, leaving behind a faint, elongated tail stretching over 1.5 degrees across the sky. This interaction produces a striking visual effect, with the bright planetary nebula at its center trailing a wispy, comet-like wake of gas and dust.

This celestial marvel is a late-stage planetary nebula, where material ejected during the dying star’s red giant phase is illuminated by the remaining hot core. The faint surrounding structures are best observed through narrowband filters, particularly in H-alpha and OIII, revealing its intricate details and contrasting colors.

Image Description and Details : SkyWatcher EQ 8 PRO Mount+TS Optics Photoline 80/480 f / 6 Triplet Super Apo - FPL-53+TS-Optics 2 "PHOTOLINE 0.79x Reducer / correctorZWO Optical ASI 1600-MM COOLED+ZWO EFWTelescope Guide: SkyWatcher EvoGuide 50ED+ZWO Optical ASI 290 MMFilters: Astronomik LRGB 1.25 "Type IIc

(Accumulation: 39h.)Locations: "Auriga" Private Observatory, Makeikha, Moscow Region, Russia

Copyright: Sviatoslav Lips

Image Description and Details :

Accumulation: 23.3 hours
HaRGB
Telescope / shooting lens: SkyWatcher Quattro 8S
Shooting Cameras: ZWO Optical ASI 1600-MM COOLED
Mounts : Celestron CGEM 1100
Telescope / Lens Guides: Celestron GuideScope 80mm f / 7.5
Guide cameras: ZWO Optical ASI 290 MM
Focus Reducers: Tele Vue Paracorr Type-II
Filters: Astronomik LRGB 1.25 "Type IIc · Baader Planetarium H-alpha 1.25" CCD 7 nm


Copyright: Sviatoslav Lips

Image Description and Details : I photographed this composite image during July-August 2020 in my private observatory (Russia, Moscow region, Makeikha SQM 20.70 mag./arc sec2; Bortle class 4).Technical Data:Telescope: SkyWatcher Quattro 8SShooting Camera: ZWO Optical ASI 1600-MM COOLEDMounts: SkyWatcher EQ 8 PRO MountTelescope Guides: SkyWatcher EvoGuide 50EDGuide camera: ZWO ASI ZWO 120mm miniFocus Reducers: TeleVue Paracorr Type-2Program: Ivan Ionov Fitstacker · by Christian Buil Iris 5.59 · Fitswork 4 · Adobe Photoshop CS 5.1Filters: Astronomik LRGB 1.25 "the Type IIc · Baader Planetarium OIII 1.25" 8.5nm-CCD · Baader Planetarium H-alpha 1.25" CCD 7 nmFrames:Astronomik B (type 2c): 10x180" -20C bin 1x1Astronomik G (type 2c): 10x180" -20C bin 1x1Astronomik R (type 2c): 10x180" -20C bin 1x1Baader Planetarium H-alpha 1.25" CCD 7 nm: 105x600" -20C bin 1x1Baader Planetarium OIII 1.25" CCD 8.5nm: 60x600" -20C bin 1x1Accumulation: 29.0 hoursDark frames: ~ 15Flat field frames: ~ 15Offset Frames: ~ 15



Copyright: Sviatoslav Lips