How do stellar binaries form?

December 3, 2018, Harvard-Smithsonian Center for Astrophysics
How do stellar binaries form?
An ALMA millimeter-wavelength image of protostellar binary stars early in their formation. (The length scale and the size of the telescope's beam are shown at the bottom.) Astronomers have studied seventeen multiple systems and found evidence supporting the model of multiple stars developing from disk fragmentation. Credit: Tobin et al.

Most stars with the mass of the sun or larger have one or more companion stars, but when and how these multiple stars form is one of the controversial central problems of astronomy. Gravity contracts the natal gas and dust in an interstellar cloud until clumps develop that are dense enough to coalesce into stars, but how are multiple stars fashioned? Because the shrinking cloud has a slight spin, a disk (possibly a preplanetary system) eventually forms. In one model of binary star formation, this disk fragments due to gravitational instabilities, producing a second star. The other model argues that turbulence in the contracting cloud itself fragments the clumps into multiple star systems. In the first case, simulations show that the two stars should be relatively close together, typically less than about 600 astronomical units (one AU is the average distance of the earth from the sun). If the second mechanism is correct, both close and wide binary pairs can form. A distinguishing feature of the turbulent fragmentation process, and one that facilitates an observational test, is that the seeds for multiplicity are produced early in the pre-stellar phases.

CfA astronomers Sarah Sadavoy and Mike Dunham were members of a team of astronomers that used the VLA and ALMA radio and millimeter-wave facilities to study seventeen protostellar systems of multiple- in the nearby Perseus cloud. The sensitive observations were able to reveal the environments of the systems and determine the presence of any small-scale rotation or surrounding material. Twelve of the systems were spatially resolved, and eight showed dust emission structures surrounding the pair. The slightly more evolved systems in the set showed no evidence for circumbinary dust; they have probably reached the end point of their early evolution and finished accreting material. In summary, about two-thirds of the systems were consistent with the disk fragmentation theory and one third was inconsistent with it. The results show that the disk fragmentation mechanism is an important one but probably not the whole story, and a larger sample should help constrain the processes even further.

Explore further: Young stellar system caught in act of forming close multiples

More information: John J. Tobin et al. The VLA/ALMA Nascent Disk and Multiplicity (VANDAM) Survey of Perseus Protostars. VI. Characterizing the Formation Mechanism for Close Multiple Systems, The Astrophysical Journal (2018). DOI: 10.3847/1538-4357/aae1f7

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cantdrive85
1.7 / 5 (12) Dec 03, 2018
Most stars with the mass of the sun or larger have one or more companion stars, but when and how these multiple stars form is one of the controversial central problems of astronomy.

It's only controversial if gravity is the only tool in your toolbox. Whereas if EM is considered the binary problem is no problem but an expectation.
https://youtu.be/jMgtWFqdPK0
jonesdave
4.2 / 5 (10) Dec 03, 2018
Most stars with the mass of the sun or larger have one or more companion stars, but when and how these multiple stars form is one of the controversial central problems of astronomy.

It's only controversial if gravity is the only tool in your toolbox. Whereas if EM is considered the binary problem is no problem but an expectation.
https://youtu.be/jMgtWFqdPK0


Lol. Youtube! Where is it written up, so that we can laugh at it without wasting bandwidth?
granville583762
5 / 5 (2) Dec 03, 2018
The shrinking cloud has a slight spin
phys.org> Most stars with the mass of the sun or larger have one or more companion stars
Gravity contracts the natal gas and dust
but how are multiple stars fashioned
the shrinking cloud has a slight spin
a disk
pre planetary system eventually forms producing a second star

So How is it Proposed
The cloud
that nurtures these starlets
has a slight spin
does no one stop to think
starlets spin
so by definition
starlet nurseries spin
this starlet nursery
has exactly the same
angularity of spin as its starlet
because that is how the plasmatic nursery collapses
As a collapsing condensing plasmatic cloud of increasing density in angularity of spin
Captain Stumpy
4.2 / 5 (10) Dec 03, 2018
@jones
Lol. Youtube! Where is it written up, so that we can laugh at it without wasting bandwidth?
don't bother

it's a thunderbutts video that is absolutely devoid of any science
jonesdave
4 / 5 (12) Dec 03, 2018
@jones
Lol. Youtube! Where is it written up, so that we can laugh at it without wasting bandwidth?
don't bother

it's a thunderbutts video that is absolutely devoid of any science


Yep. I'd already assumed that :) Science is a foreign concept to the mythologists.
cantdrive85
1.9 / 5 (13) Dec 03, 2018
Science is a foreign concept to the mythologists.

As the darkists blame all on everything dark, black, and invisible.
You must have a simple explanation for the pervasiveness of the binary which has no explanation from the gravity only perspective. I bet there is a dark faerie twirling in her dust to create a mirror image of itself. Voila!
Da Schneib
4.5 / 5 (8) Dec 03, 2018
ALMA is an extraordinary instrument. New data and new understanding seem to come from it on an almost weekly basis. It's visually quite impressive, as the VLA is (see the movie 2010: Odyssey II for film of the VLA). Like the VLA, its antennae can be moved to configure it for various tasks (often referred to as "zooming in or out"). The light it detects is millimeter and sub-millimeter; this is EHF microwave and terahertz radiation. It is notable that this type of radiation has great penetrating power through gas and dust.

This particular discovery is very important to star formation theories, and seems instead of dismissing either of the two main theories to show that multiple star systems can form either way. The more we look the more we will find out. This instrument will be making new discoveries for decades to come.
jonesdave
4.2 / 5 (10) Dec 03, 2018
Science is a foreign concept to the mythologists.

As the darkists blame all on everything dark, black, and invisible.
You must have a simple explanation for the pervasiveness of the binary which has no explanation from the gravity only perspective. I bet there is a dark faerie twirling in her dust to create a mirror image of itself. Voila!


Dafuq is that crap?
Da Schneib
3.9 / 5 (11) Dec 03, 2018
You can smell the crank trolls when they start rejecting data.
Solon
1.7 / 5 (12) Dec 03, 2018
"You can smell the crank trolls when they start rejecting data."

Data that only specialists can make head nor tail of. Try creating an image from ALMA raw data and lets see your results. And I have yet to see proof that any of these objects are even stars, and there will never be any such proof.
Captain Stumpy
4.3 / 5 (11) Dec 03, 2018
@solon
Data that only specialists can make head nor tail of
https://ocw.mit.e...ophysics

And I have yet to see proof that any of these objects are even stars, and there will never be any such proof
don't yall eu ever get tired of being proven wrong?
https://arxiv.org...6434.pdf

jonesdave
4.5 / 5 (8) Dec 04, 2018
"You can smell the crank trolls when they start rejecting data."

Data that only specialists can make head nor tail of. Try creating an image from ALMA raw data and lets see your results. And I have yet to see proof that any of these objects are even stars, and there will never be any such proof.


Look at the orbital data, use Kepler's laws. Idiot.
rrwillsj
4.4 / 5 (7) Dec 04, 2018
Ahh cant & saloon, preaching their cant of befuddlement. Complaining that DM/DE & Gravity are invisible & therefore "cant" be true.

While worshiping invisible deities, flinging invisible thunderbolts from invisible heavens. For the good of our invisible souls!

You two frauds should contemplate the definition of cant. You are both in violation of the moral standards your primitive tribal superstitions claim to personify!
Solon
1.8 / 5 (5) Dec 04, 2018
So Captain, you will take on the task of producing an image from the ALMA raw data? Some info to help you get started:
Archive & Data Retrieval
https://help.alma...etrieval
Captain Stumpy
4.2 / 5 (5) Dec 04, 2018
@solon
So Captain, you will take on the task of producing an image from the ALMA raw data?
sure thing, if you're willing to put up cash with a mediator that will be fair and impartial

I can suggest a few people that will do that if you like

the rules are simple and taken from your post:
I have to use the ALMA data for the purpose of "producing an image"

I succeed and I get the cash

how much are you willing to put up because I won't bother for petty cash - it's the christmas season and I have children to buy for

if you're nice about it I will even put your name as the chief contributing patron to the gifts
Some info to help you get started:
Archive & Data Retrieval
I already have the links

I've had them for a while
jonesdave
4.4 / 5 (7) Dec 04, 2018
Data that only specialists can make head nor tail of.


And that is why we have specialists. You would not expect a bricklayer to perform neurosurgery, would you?
And not all raw data is impenetrable. I have said to electric comet wooists to go look through the Giotto and Rosetta magnetometer data for their non-existent discharges. And to see that there is a cavity around the comet devoid of a magnetic field. I downloaded the Giotto data, and it is clear as day. 0 nT = no magnetic field = no electric discharge woo. That data was available many years before the idiots Thornhill and Talbott invented their crap. As were the papers reporting it.
Solon
2 / 5 (8) Dec 04, 2018
"And that is why we have specialists."
Ah yes, specialists. People who know more and more about less and less, and couldn't explain what they do know to a barmaid.
"No physical theory is worth much if it cannot be explained to a barmaid."
— Ernest Rutherford (c.1915)
And why is the proprietory data in ALMA information when the data has been collected at the taxpayers expense? Something doesn't smell right.
Captain Stumpy
4.2 / 5 (5) Dec 04, 2018
@solon
And why is the proprietory data in ALMA information when
so that's a no, then?
Ah yes, specialists. People who know more and more about less and less,
no
people who know more and more about a specific area and drive the boundaries of ignorance away so that we may propel ourselves beyond cult beliefs in pseudoscience woo
"No physical theory is worth much if it cannot be explained to a barmaid."
— Ernest Rutherford (c.1915)
explaining it doesn't mean understanding it

also note, a barmaid rarely has a vested interest in understanding advanced specialist information and so will not try to comprehend the said explanation

it's about incentive - a specialist has the incentive to understand and study a topic because it directly affects the specialist's ability to advance (etc)
Ultron
2.3 / 5 (7) Dec 04, 2018
You can smell the crank trolls when they start rejecting data.


Yeah, professional physicist dont reject data, they just select the data which fits their theory :)
Da Schneib
3.7 / 5 (3) Dec 04, 2018
I'll tell you what they're not doing: they're not making it all up. That's one hell of a lot of expensive equipment and expensive computer time they're using.
rrwillsj
3.4 / 5 (5) Dec 04, 2018
Oh my the cultist Utron jumping in to defend his sockpuppet fellow woodolts.

Where is your contribution to the data? From any of you frauds?

Where is your patented inventions based upon your cultist delusions?

No. the ouiji board and brass spirit horn do not count. You scammers weren't clever enough to invent those tricks!

Tell you what, I will accept an odyllic detector or a flying saucer (airborne) or an orgone box. When you allow professional, certified engineers & experienced stage illusionists
to inspect & confirm the validity of your claims.
Da Schneib
3 / 5 (2) Dec 04, 2018
Unfortunately, @rrwills, even stage magicians can be fooled. James Randi never admitted anthropogenic global climate change and I got kicked off his site for presenting evidence of it.
torbjorn_b_g_larsson
3.4 / 5 (5) Dec 05, 2018
This particular discovery is very important to star formation theories, and seems instead of dismissing either of the two main theories to show that multiple star systems can form either way. The more we look the more we will find out. This instrument will be making new discoveries for decades to come.


Yes.

Speaking of dismissing:

Ah yes, specialists. People who know more and more about less and less, and couldn't explain what they do know to a barmaid.
(followed by a conspiracy theory).

Since you believe in made up conspiracies rather than data - and note that ALMA is too large to even be a conspiracy (but you need to study data on conspiracy theory modeling to see that) - our responses is not for you but the people you want to share your delusions with.

Experts are ... well, experts. They have made the internet you comment on, so obviously they know more and more correct in general than you do. Common people grok ALMA. Why don't you?

Ultron
1 / 5 (1) Dec 05, 2018
Oh my the cultist Utron jumping in to defend his sockpuppet fellow woodolts.

Where is your contribution to the data? From any of you frauds?

Where is your patented inventions based upon your cultist delusions?

No. the ouiji board and brass spirit horn do not count. You scammers weren't clever enough to invent those tricks!

Tell you what, I will accept an odyllic detector or a flying saucer (airborne) or an orgone box. When you allow professional, certified engineers & experienced stage illusionists
to inspect & confirm the validity of your claims.


You sound like medieval inquisitor, full of hate, calling for torturing and killing of heretics.

I can assure you, I personally do care a lot about data and observations. Im just disgusted by watching "professional physicists" selectively using data which suits them and ignoring data and facts which are not in line of what they want to push through.
yep
1 / 5 (1) Dec 07, 2018
Many of you are old fools that know to much to learn anything, and are always forgetting history.
https://www.ncbi....2373380/
Captain Stumpy
5 / 5 (1) Dec 07, 2018
@Ultron
Yeah, professional physicist dont reject data, they just select the data which fits their theory
Im just disgusted by watching "professional physicists" selectively using data which suits them and ignoring data and facts which are not in line of what they want to push through
this is, at best, an untested claim, and based solely on your attitudinal statement, thus it's opinion

but considering the current advancement in physics as well as the track record of physicists, it can be considered a false claim

http://www.auburn...ion.html

.

.

@yep
Many of you are
stopped there

the "uphill battle" is a good thing as it establishes *facts* and allows the *facts* be validated before accepted as a Theory

it's not like electric woo bullsh*t where random pictures of scarring are equivalent enough to claim plasma carved the grand canyon...

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