Hartl-Dengel-Weinberger 3 (HDW 3) (James E.)

Hartl-Dengel-Weinberger 3 (HDW 3)

HDW3 is a very faint ancient planetary nebula about 2500 light years away in Perseus. It was discovered in 1983 by H. Hartl, J. Dengel and R. Weinberger. This project began in 2022 and additional data was added in 2023 in an effort to reveal some of the fainter parts of the nebula. A couple of the attached revisions show moderately stretched images of Ha and OIII, while one revision locates the white dwarf progenitor star named WD0322+452.

An image on ImagingDeepSpace.com has a great description of HDW3: "The progenitor star is the small blue star at the 5 o-clock position just below the large yellow star in HDW 3 [see my revision for closeup]. The progenitor is not, as one would expect, in the centre of the nebula. This is because it is moving rapidly in a north-westerly direction. It is moving through a dense area of interstellar medium (ISM). This ISM is slowing down HDW 3, creating a shock front and the unusual "braided" appearance. As the star isn't slowed by the ISM it has continued to move and is thus no longer at the centre of HDW 3 and is slowly overtaking HDW 3. This causes the shock front to be brighter as it's getting more ultraviolet radiation, whereas the opposite side of HDW 3 is getting less UV radiation and has become invisible. This movement of the star causes differential excitation of the shell. OIII emission, which requires higher energy of the ionizing radiation than HII emission, only happens close to the star."

Imaged over many nights: Nov 23-24, Dec 3-4, 2022; Oct 4, 9-10, Nov 2, 5, 7-8, 2023.

Final
Original
B
C
D

B

Description: Ha_38 hours_denoised

Uploaded: ...

C

Description: OIII_40 hours_denoised

Uploaded: ...

D

Description: Location of white dwarf

Uploaded: ...

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Status	Advanced success
Started	...
Astrometry.net job	8722004
PixInsight job	EJ6J6CKZWPKXPV3VG898DVSGXCPZ5GBR
PixInsight queue size	n/a
PixInsight stage	TASK_LOG

RA (center)	03h27m03s.62
RA (top/left)	03h30m23s.35
RA (top/right)	03h23m56s.87
RA (bottom/right)	03h23m46s.42
RA (bottom/left)	03h30m07s.72

Dec (center)	+45°25′19″.7
Dec (top/left)	+45°46′50″.4
Dec (top/right)	+45°50′09″.2
Dec (bottom/right)	+45°03′27″.8
Dec (bottom/left)	+45°00′12″.8

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