APOD: M43: Orion Falls (2018 Dec 12)

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APOD Robot
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APOD: M43: Orion Falls (2018 Dec 12)

Post by APOD Robot » Wed Dec 12, 2018 5:05 am

Image M43: Orion Falls

Explanation: Is there a waterfall in Orion? No, but some of the dust in M43 appears similar to a waterfall on Earth. M43, part of the Orion Molecular Cloud Complex, is the often imaged but rarely mentioned neighbor of the more famous M42. M42, which includes many bright stars from the Trapezium cluster, lies above the featured scene. M43 is itself a star forming region and although laced with filaments of dark dust, is composed mostly of glowing hydrogen. The entire Orion field, located about 1600 light years away, is inundated with many intricate and picturesque filaments of dust. Opaque to visible light, dark dust is created in the outer atmosphere of massive cool stars and expelled by a strong outer wind of protons and electrons.

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De58te
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Re: APOD: M43: Orion Falls (2018 Dec 12)

Post by De58te » Wed Dec 12, 2018 11:33 am

Sometimes naming these objects is subjective, depended on viewpoint. What if this picture was the mirror image? Instead of facing north when you took this picture, you faced south? Then it would look like flames shooting up. Then its name would be Orion Rises.

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Re: APOD: M43: Orion Falls (2018 Dec 12)

Post by starsurfer » Wed Dec 12, 2018 12:58 pm

There is a Waterfall Nebula south of the Orion Nebula that is part of the NGC 1999 complex.

Grumpa

Re: APOD: M43: Orion Falls (2018 Dec 12)

Post by Grumpa » Wed Dec 12, 2018 1:23 pm

The calendar on the link advertised on this page lacks a winter solstice.

Wulflyng

Re: APOD: M43: Orion Falls (2018 Dec 12)

Post by Wulflyng » Wed Dec 12, 2018 6:54 pm

This, to me, looks more like a dog's head seen from below and to the dog's left.

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Re: APOD: M43: Orion Falls (2018 Dec 12)

Post by neufer » Wed Dec 12, 2018 8:25 pm

Click to play embedded YouTube video.
Wulflyng wrote:
Wed Dec 12, 2018 6:54 pm

This, to me, looks more like a dog's head
seen from below and to the dog's left.
Art Neuendorffer

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Re: APOD: M43: Orion Falls (2018 Dec 12)

Post by Boomer12k » Thu Dec 13, 2018 3:59 am

That is just an incredible shot... so much detail...

My shot of M43 (The Running Man Nebula) back in 2011 with my 10" Meade LX-200 and DSI II color camera...

Now Question:
"Opaque to visible light, dark dust is created in the outer atmosphere of massive cool stars and expelled by a strong outer wind of protons and electrons. "

Does that make "Dust"....Ash??? Or is is something created, not burnt...

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Re: APOD: M43: Orion Falls (2018 Dec 12)

Post by Chris Peterson » Thu Dec 13, 2018 5:16 am

Boomer12k wrote:
Thu Dec 13, 2018 3:59 am
Now Question:
"Opaque to visible light, dark dust is created in the outer atmosphere of massive cool stars and expelled by a strong outer wind of protons and electrons. "

Does that make "Dust"....Ash??? Or is is something created, not burnt...
"Burn" is generally understood as combustion- an exothermic, oxidative reaction. Fire. That is not what is happening in stars. "Ash" is generally understood to be the non-combusted solid residue of combustion. "Dust" is precisely the right word: fine particles of solid material. That is what is produced in stars by various fusion processes.
Chris

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neufer
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Re: APOD: M43: Orion Falls (2018 Dec 12)

Post by neufer » Fri Dec 14, 2018 3:45 pm

Chris Peterson wrote:
Thu Dec 13, 2018 5:16 am
Boomer12k wrote:
Thu Dec 13, 2018 3:59 am

"Opaque to visible light, dark dust is created in the outer atmosphere of massive cool stars and expelled by a strong outer wind of protons and electrons. "

Does that make "Dust"....Ash??? Or is is something created, not burnt...
"Burn" is generally understood as combustion- an exothermic, oxidative reaction. Fire. That is not what is happening in stars. "Ash" is generally understood to be the non-combusted solid residue of combustion.

"Dust" is precisely the right word: fine particles of solid material. That is what is produced in stars by various fusion processes.
https://en.wikipedia.org/wiki/Polycyclic_aromatic_hydrocarbon wrote: <<Polycyclic aromatic hydrocarbons (PAHs, also polyaromatic hydrocarbons or polynuclear aromatic hydrocarbons) are hydrocarbons—organic compounds containing only carbon and hydrogen—that are composed of multiple aromatic rings (organic rings in which the electrons are delocalized). In October 2018, researchers reported low-temperature chemical pathways from simple organic compounds to complex PAHs. Such chemical pathways may help explain the presence of PAHs in the low-temperature atmosphere of Saturn's moon Titan, and may be significant pathways, in terms of the PAH world hypothesis, in producing presursors to biochemcals related to life as we know it.

PAHs may be abundant in the universe. They seem to have been formed as early as a couple of billion years after the Big Bang, and are associated with new stars and exoplanets. More than 20% of the carbon in the universe may be associated with PAHs. PAHs are considered possible starting material for the earliest forms of life. Light emitted by the Red Rectangle nebula and found spectral signatures that suggest the presence of anthracene and pyrene. This report was considered a controversial hypothesis that as nebulae of the same type as the Red Rectangle approach the ends of their lives, convection currents cause carbon and hydrogen in the nebulae's cores to get caught in stellar winds, and radiate outward. As they cool, the atoms supposedly bond to each other in various ways and eventually form particles of a million or more atoms. Adolf Witt and his team inferred that PAHs—which may have been vital in the formation of early life on Earth—can only originate in nebulae.

More recently, fullerenes (or "buckyballs"), have been detected in other nebulae. Fullerenes are also implicated in the origin of life; according to astronomer Letizia Stanghellini, "It's possible that buckyballs from outer space provided seeds for life on Earth." In September 2012, NASA scientists reported results of analog studies in vitro that PAHs, subjected to interstellar medium (ISM) conditions, are transformed, through hydrogenation, oxygenation, and hydroxylation, to more complex organics—"a step along the path toward amino acids and nucleotides, the raw materials of proteins and DNA, respectively". Further, as a result of these transformations, the PAHs lose their spectroscopic signature which could be one of the reasons "for the lack of PAH detection in interstellar ice grains, particularly the outer regions of cold, dense clouds or the upper molecular layers of protoplanetary disks.">>
Art Neuendorffer