A rarely-imaged faint Planetary Nebula (PNe) hiding within Lynds Bright Nebula 381 (LBN 381) in Cygnus, first noted by Ronald Weinberger in 1977. This PNe was brought to my attention by Barry Wilson in his recent excellent image of LBN 381.

A planetary nebula forms when a star can no longer support itself by fusion reactions in its centre. The gravity from the material in the outer part of the star takes its inevitable toll on the structure of the star, and forces the inner parts to condense and heat up. The high temperature central regions drive the outer half of the star away in a brisk stellar wind, lasting a few thousand years. This ejection has resulted in this bubble-like structure. When the process is complete, the remaining core remnant is uncovered and heats the now distant gases and causes them to glow.

This is a highly evolved and thus extremely faint PNe with very low surface brightness of between 22.1 and 25.8 mag/sq-arcsec. Over time this will become so faint that it will completely disappear. This image shows the existence of an outer OIII shell that according to Ronald Weinberger hasn't been captured before.

Image captured jointly by myself and Alistair Macpherson at sites in Shropshire, England and Alcalali, Spain. Because of the faintness of this target we chose to go deep, capturing a total of 46 hours 30 minutes of data, with 34 hours at bin 2x2.

46 hours 30 minutes in total.

Red 21x600s bin 1x1

Green 12x600s bin 1x1

Blue 20x600s bin 1x1

Lum 19x600s bin 1x1

Ha 17x1800s bin 2x2 and 35x1200s bin 2x2

OIII 43x1200s bin 2x2

Shropshire: APM TMB 152 F8 LZOS, 10 Micron GM2000HPS, SX H694

Alcalali: APM TMB 152 F8 LZOS, 10 Micron GM2000HPS, QSI6120ws8