HFG1 (PK 136+05) is a very old large, low-surface-brightness planetary nebula in Cassiopeia that was discovered by Heckathorn, Fesen, and Gull in 1982. It surrounds, and was produced by, a binary star system (V664 Cas) that is moving rapidly through our Galaxy. The star is moving towards the lower left of the image. As HFG1 plows through the interstellar medium, a bluish bowshock is produced; and a red trail of gas is left behind in its wake.

Astrodon Blue: 10x300"
Astrodon Green: 10x300"
Astrodon Lum: 11x600"
Astrodon Red: 10x300"
Astrodon OIII: 35x1800s bin 2x2
Astrodon Ha: 33x1800s bin 2x2
Total Integration: 38 hours
Captured on my dual rig in Spain.
Scopes: APM TMB LZOS 152 (6" aperture 1200mm focal length)
Cameras: QSI6120wsg8
Mount: 10Micron GM2000 HPS

Ref: Monthly Notices of the Royal Astronomical Society 396(2):1186 - 1188 · June 2009