Sh2-308: Explosive Chaos (Alex Woronow)

Sh2-308: Explosive Chaos

Sh2-308: Explosive Chaos

TAO 150: Deep Sky West

EXPOSURES:
…R……12 x 300 sec.
…B….11 x 300
…G……12 x 300
…O.…23 x 1800
…H.…12 x 1800
Total exposure   33.3 hours

Image Width: 1.4 deg
Processed by Alex Woronow (2021) using PixInsight, Topaz, StarXTerminator (in PI), SWT

The bubble, Sh2-308, marks the beginning of the end for the Wolf-Rayet star WR-6. The life paths of WR stars are poorly known and often debated. Most scientists believe this bubble of debris ejected from the outer layers of WR-6 presages its death in a supernova event. All agree that the massive WR stars live brief lives that end in a violent supernova explosion, but how these rare stars traverse most of their lives remains a somewhat open question.

At the point before Sh2-308 formed, WR-6 probably became stratified with an outer layer of hydrogen, then He, C, Ne, O, Si, and finally Fe in their cores. SH2-308 formed when WR-6 violently threw off its outer layers of largely lighter, exhausted fissionable gasses and fission products, just 70,000 years ago. That violent event was accompanied by intense heat, radiation, and solar winds—up to 5.4 million miles/hour--stripping away the layers. Consequently, unlike a child’s soap bubble, the SH2-308 bubble shows an imprint of its violent origin with twisting gas streamers, shock fronts, and tattered gas ropes and sheets. I have tried to reveal those signatures of violence in this rendition of Sh2-308.

As many of you probably know, this is a shy target, hard to recognize on a single subframe, and not all that obvious in stacks. Well, that kind of issues a challenge to make the bubble dominant in the image. So this is a Target-Forward rendering of Sh2-308, for something a little different, a bit artsy, and for your consideration.

Alex

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Status	Advanced success
Started	...
Astrometry.net job	5356095
PixInsight job	L3IB7R8G7FL88HL0PAH0GFT4NKRD8FAS
PixInsight queue size	n/a
PixInsight stage	TASK_LOG

RA (center)	06h54m36s.48
RA (top/left)	06h51m48s.69
RA (top/right)	06h57m55s.40
RA (bottom/right)	06h57m26s.11
RA (bottom/left)	06h51m16s.48

Dec (center)	-23°52′33″.1
Dec (top/left)	-23°14′23″.10
Dec (top/right)	-23°23′05″.1
Dec (bottom/right)	-24°30′26″.7
Dec (bottom/left)	-24°21′41″.2

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