When stars die they eject lots of gas which forms a planetary nebula. In rare instances, like Abell 78, the remaining core of the nebula gets hot enough to resume nuclear activity, ejecting more filaments of gas into the older nebula, resulting in unique filamentary structures.
Acquisition Details
Hα = 26x10min
OIII = 34x10min
RGB = 30x5min each
Total = 17hrs 30min
