Hartl-Dengel-Weinberger 3: An exceedingly faint ancient planetary nebula

by Luca Marinelli

Objects in field: PK149-09.1

Equipment: TS-Optics 250mm/10" ONTC f/4 Newtonian (carbon tube), QHYCCD QHY268 M

Integration: 85h 51m

Hartl-Dengel-Weinberger 3 (HDW 3, PK149.09-1, PN G149.4-09.2) is an extremely faint and rarely imaged ancient planetary nebula in the constellation Perseus. The progenitor star is the blue star at 4 o'clock position from the bright central yellow star. The progenitor star is not centrally located due to the fast motion in a northwesterly directory of the PN through the interstellar medium, which…