Star "birth" captured by ALMA

[seasmith]

pirogronian » Tue Aug 27, 2013 12:48 pm

celeste, green light reflecting on dust cloud surface suggest that there is as you said. However magnetic field arounding dust cloud suggest that this is kind of closed circuit. What it's powered by? BTW linked article seems to be behind paywall, it's a pity..

A bit more info here at the ALMA site:
http://almaobservatory.org/en/press-roo ... -starbirth
[the Chileans are on strike now, so galaxy/star birth is temporarily aborted ]


The classic 'bowl and toroid' configuration of a filamental node may well be intaking, not ejecting, dusty plasma material, via the toroidal disk.
imho, Birkland currents act as conductors and condensers.
÷

[ThickTarget]

I would assume that the opaque matter region is feeding the entire process, a sort of cosmic amnion whereby the matter enters both the north and south magnetic bowls, gathers at the confinement domes whose excess pressure is relieved and shot out as a jet of material.

That's not really consistent with what was observed. One of ALMA's great strengths is very fine imaging spectroscopy which allows images to be deconstructed into slices with different doppler speeds. If you look at the original paper below the article on ESO's site you can see the doppler break down of the data. This shows one jet has a negative velocity and the other a positive one. If we had inflow and outflow we would see only negative or positive velocities.

http://www.eso.org/public/news/eso1336/

[celeste]

ThickTarget, I agree that,( while it can be almost painful at times), it is well worth the time to look at the source material. Compare what they found here http://sci.esa.int/herschel/48623-hersc ... ould-belt/ to this http://www.eso.org/public/archives/rele ... o1336a.pdf (O.K., only the second one is source)
In Gould's Belt they find filaments 0.3 ly wide, while from HH47C, they see a "lobe"' .08pc (.26ly)wide extending outwards.
So, HH46/47 shows signs of star formation , with "jets" about .26ly wide extending from the star, and a dense wall of dust expanding past the star. In Gould's Belt, we see a bright ring of blue stars(young says the mainstream), in filaments ~0.3ly wide,surrounding the local chimney. The Local Chimney is defined at it's edges by a surrounding shell of expanding neutral gas and dust. Does not take a rocket scientist to see we are looking at the same thing.
Now here is how you know someone in the mainstream is looking at this process the wrong way: With Gould's Belt, they started with the the stream of stars flowing down the center (the Pleides stream), and suggested that what was happening there (supernova explosions?), caused the expansion of dust,and the formation of Gould's Belt. With HH46/47, they are starting with the young protostar,and trying to explain not only the flow in the jets, but how this "feeds the parent cloud turbulence".
In other words,is it the stream of stars flowing down the center that blasts out the neutral gas and dust, and causes star formation in the surrounding ring , or is it star formation that causes "jets",which then influence the nearby dust cloud? The first approach was right, they just needed the mechanism. A huge scale (Pleides stream is hundreds of stars or more)current filament causes both the ejection of neutrals (Marklund Convection), and a driving up of toroidal star forming currents.

[viscount aero]

I would assume that the opaque matter region is feeding the entire process, a sort of cosmic amnion whereby the matter enters both the north and south magnetic bowls, gathers at the confinement domes whose excess pressure is relieved and shot out as a jet of material.

That's not really consistent with what was observed. One of ALMA's great strengths is very fine imaging spectroscopy which allows images to be deconstructed into slices with different doppler speeds. If you look at the original paper below the article on ESO's site you can see the doppler break down of the data. This shows one jet has a negative velocity and the other a positive one. If we had inflow and outflow we would see only negative or positive velocities.

http://www.eso.org/public/news/eso1336/

Maybe I needed to clarify: The jets are as I suggested, one going away from earth and the other coming towards earth, as the article states. These are polar jets expelling matter from the center star outwards, as I said. The "amniotic seeding" part was speculative. But I read the article correctly about the direction of the jetting material--it is going in opposite directions outwards from the center.

If matter is also being simultaneously compressed and in-falling in the midst of an electrical field at each pole then that theoretical process does not involve polar ejection and is not represented as a high velocity ejecta structure. It is not ionized but is however suggested (below).

But ejecta matter is being expelled as polar jets opposite each other. Hence, the shedding of material and pressure from the process of matter compression. If this is what is happening or not has yet to be absolutely determined. However the imaging team itself refers to the enshrouding region of matter as the "parent cloud":

"Diego Mardones (Universidad de Chile), another co-author, emphasises that "this system is similar to most isolated low mass stars during their formation and birth. But it is also unusual because the outflow impacts the cloud directly on one side of the young star and escapes out of the cloud on the other. This makes it an excellent system for studying the impact of the stellar winds on the parent cloud from which the young star is formed."

Hence my mention of the "seeding" effect of the "parent cloud." If it is a parent cloud then it must be feeding the star and in-falling. Parents feed their children

[ThickTarget]

I now realise I misread your post, I thought you meant in one side out the other. I can only apologise.

Hence my mention of the "seeding" effect of the "parent cloud." If it is a parent cloud then it must be feeding the star and in-falling. Parents feed their children

Parent cloud means the star collapsed from it, it does not imply it is still accreting matter.

[viscount aero]

I now realise I misread your post, I thought you meant in one side out the other. I can only apologise.

No problem, mate

Hence my mention of the "seeding" effect of the "parent cloud." If it is a parent cloud then it must be feeding the star and in-falling. Parents feed their children

Parent cloud means the star collapsed from it, it does not imply it is still accreting matter.

Sure, that is the mainstream interpretation. I understand. In my suggestion the matter is perpetually in-falling and being compressed, ie, pressurized then shot out, not "accreted" per the "core accretion theory." Compression of matter is in "real time" and much faster a process than the improbable core accretion idea. But they're similar ideas.