The origin of the s-star cluster at the galactic center

Jun 05, 2013

(Phys.org) —Scientists Fabio Antonini, of the Canadian Institute for Theoretical Astrophysics, and David Merritt, of the Rochester Institute of Technology, have developed a new theory that explains the orbits of the massive young stars that closely orbit the black hole at the center of the Milky Way.

The discovery of these called "S-stars" provided an unprecedented opportunity for studying the black hole at the galactic center itself, but it also raised new questions: how were massive orbiting in a region too violent for them to have formed there? They could not have formed where they are observed because of the strong gravity of the supermassive black hole, implying that they had to have migrated from further out. When theoreticians produced models explaining the migration of the S-stars toward the center the observed orbits didn't match the models. Why were the orbits observed different from what was predicted?

Dr. Antonini is offering the best answers to date for this puzzle in his Thursday afternoon talk at the annual meeting of the Canadian Astronomical Society (CASCA). In "The Origin of the S- at the Galactic Center," Antonini is presenting a for the origin and dynamics of the S-stars.

Explaining how these stars managed to get so close in only tens of millions of years since they formed has been a challenge. "Theories exist for how migration from larger distances has occurred, but have up until now been unable to convincingly explain why the S-stars the galactic center the way they do," Antonini said. "As main-sequence stars, the S-stars cannot be older than about 100 million years, yet their orbital distribution appears to be 'relaxed', contrary to the predictions of models for their origin." Antonini and Merritt's model suggests that the S-stars formed farther out from the galactic center, migrated within their lifetime to the region where they are observed and subsequently attained the observed orbital shapes by interacting gravitationally with other stars near the central black hole.

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3-dimensional visualization of the stellar orbits in the Galactic center based on data obtained by the W. M. Keck Telescopes between 1995 and 2012. Stars with the best determined orbits are shown with full ellipses and trails behind each star span ~15-20 years. These stars are color-coded to represent their spectral type: Early-type (young) stars are shown in teal green, late-type (old) stars are shown in orange, and those with unknown spectral type are shown in magenta. Stars without ellipses are from a statistical sample and follow the observed radial distributions for the early (white) or late (yellow/orange) type stars. These stars are embedded in a model representation of the inner Milky Way provided by NCSA/AVL to provide context for the visualization. The movie begins at the very center of the Galaxy, ~0.015 pc from the supermassive black hole, in the year 1893, and pulls away to a distance of 0.2 pc as the movie reaches the year 2013, ending from the viewing angle of Earth. Credit: (c) University of Illinois

Antonini's and Merritt's research builds on new insights on how stellar orbits at the galactic center evolve due to the joint influence of gravitational interactions with other stars and relativistic effects due to the supermassive black hole.

"Theoretical modeling of S-star orbits is a means to constrain their origin, to probe the dynamical mechanisms of the region near the and," says Merritt, "indirectly to learn about the density and number of unseen objects in this region."

Supermassive are believed to inhabit the center of most, if not all, massive galaxies. How they form and grow is intimately connected to the formation of the galaxies they inhabit. The black hole in the center of our own galaxy, named Sgr A* (pronounced Sagittarius A-star), is the closest and most extensively studied example. By tracking the orbits of the S-stars over the past several years, astronomers have been able to conclusively show that the object they orbit is indeed a .

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Ophelia
not rated yet Jun 05, 2013
Antonini and Merritt's model suggests that the S-stars formed farther out from the galactic center, migrated within their lifetime to the region where they are observed and subsequently attained the observed orbital shapes by interacting gravitationally with other stars near the central black hole.
Hmm. So, this is a multi-body problem and not a two-body problem. Who would have thunk it?
Tuxford
1 / 5 (8) Jun 05, 2013
Another patch to prop up a failing Huge Bang Fantasy: that all matter was created in a single event. Their explanation rests on the need to explain the migration of the large stars. Instead, the simpler explanation aligns with LaViolette's SQK model, where the stars grow in place naturally from within, but at an accelerated pace, caused by their proximity to the massive galactic core star. Their origin is as small daughter stars condensed from material ejected from periodic instabilities of the mother core star.

So rather than investigate alternative means, continue to ignore a simpler explanation, as it violates science dogma. That is the easier, and safer approach for lazy minds. (Scientific fundamentalism may eventually be recognized as a mental illness, as some have suggested is religious fundamentalism.)
cantdrive85
1 / 5 (6) Jun 05, 2013
When theoreticians produced models explaining the migration of the S-stars toward the center the observed orbits didn't match the models. Why were the orbits observed different from what was predicted?


Hmmm, could it be because they are using the incorrect physics? Nahh, couldn't be!

cantdrive85
1 / 5 (9) Jun 05, 2013
According to Plasma Cosmology Theory;

"Stars are an electrical phenomenon. Stars are not formed by gravitational accretion but in the incomparably more powerful plasma z-pinch. The galactic plasmoid is a concentrated z-pinch. As a z-pinch subsides, experiment shows that a number of consolidated objects that formed along the pinch scatter like buckshot. So stars born in the plasmoid will initially have random eccentric orbits. Stellar rotation is imparted by the pinch vortex and should be similar in the group. The stars beyond 0.02 parsec from the Galactic Center show different kinematics and stellar properties from those stars inside that limit. It indicates a discontinuity in the properties of the plasma environment rather than something intrinsic to the stars.

So the orbits of these stars is PREDICTED by PC, based upon laboratory experimentation of plasmoids. The very same type of plasmoids that are created at z pinches along Birkeland currents.
Weird!
GSwift7
5 / 5 (5) Jun 05, 2013
Antonini's and Merritt's research builds on new insights on how stellar orbits at the galactic center evolve due to the joint influence of gravitational interactions with other stars and relativistic effects due to the supermassive black hole


The relativistic effects wouldn't be that much. The closest of the S-stars, named S2, gets up to 2% of the speed of light at its closest approach to Sagt-A, with acceleration from the black hole topping out at 1/6th of Earth surface gravity. It would need to get a bit closer to Sagt-A for us to see anything really cool. However, S2 is the fastest orbital object ever observed, and therefore is unique as a test for relativistic effects, however small they are in that case.

I wouldn't want to be anywhere near two S-stars colliding in orbits that fast, or get hit by any object thrown out by a near miss either.

Wiki for S2:

http://en.wikiped...2_(star)

Difficult to imagine such things.
GSwift7
5 / 5 (6) Jun 05, 2013
So the orbits of these stars is PREDICTED by PC,


Not they aren't. Orbits based on a force which diminishes as the cube of distance are not sustainable unless they are perfectly circular, and only at precise distances, else they decay almost immidiately. Since we observe the orbits of the S-stars to be eliptical, we know that they are under the influence of a force that diminishes as the square of distance. EM force does not do this. You cannot ignore this basic rule. If you deny gravity, then there is some other force that acts on the square of distance. If you claim EM is even part of the force, then it doesn't work. It must be exactly the square of distance, not 99% or 101%. Any EM force working here would throw the whole thing off. You cannot be right. Basic math forbids it. Not even a little bit.
cantdrive85
1 / 5 (8) Jun 05, 2013
From the preeminent plasma physicist Anthony Peratt sees it differently from you;

"Perhaps the most important characteristic of electromagnetism is that it obeys the longest-range force law in the universe. When two or more non-plasma bodies interact gravitationally, their force law varies inversely as the square of the distance between them; 1/4 the pull if they are 2 arbitrary measurement units apart, 1/9 the pull for a distance of 3 units apart, 1/16 the pull for 4 units apart, and so on. When plasmas, say streams of charged particles, interact electromagnetically, their force law varies inversely as the distance between them, 1/2 the pull if they are 2 arbitrary measurement units apart, 1/3 the pull for a distance of 3 units apart, 1/4 the pull for 4 units apart, and so on...." con't
cantdrive85
1 / 5 (8) Jun 05, 2013
con't
"So at 4 arbitrary distance units apart, the electromagnetic force is 4 times greater than that of gravitation, relatively speaking, and at 100 units, apart, the electromagnetic force is 100 times that of gravitation. Moreover, the electromagnetic force can be repulsive if the streams in interaction are flowing in opposite directions. Thus immense plasma streams measured in megaparsecs, carrying galaxies and stars, can appear to be falling towards nothing when they are actually repelling."

As I have stated repeatedly, a better understanding of plasma physics is necessary, jr. high EM concepts must be expanded upon by those charged with studying these phenomenon..

http://www.plasma...ces.html
GSwift7
5 / 5 (6) Jun 05, 2013
IF Peratt actually said that, then his understanding of the subject he preaches about is nill. However, I think it is more likely that you have mis-quoted something or taken your quote from a source that mis-quoted him. Nobody educated about this topic would make such a basic mistake. You need to look up the wiki on EM force.

ONLY a force that diminishes with the SQUARE of distance will produce ELIPTICAL orbits, as we observe everywhere. There is no exception to this basic rule of math. In fact, you can do a good approximation of this experimentally with a baseball in your back yard. The whole field of ballistic trajectory is based on this. If gravity was an EM force, then every cannon ball ever shot in history would have missed its target, satellites would be in the wrong orbits, and the Sun would have no planets around it. Earth's orbit is not possible with anything other than a SQUARED force law.
GSwift7
5 / 5 (5) Jun 05, 2013
Here, I'll make it easy for you. Here's a link to the page on the "Magnetic Moment" which is the technical term describing the force we are talking about. You could also refer to the dipole moment, as it is related and this information is found there as well as many other sources.

http://en.wikiped...e_moment

Here's the last sentence of the first paragraph:

The dipole component of an object's magnetic field is symmetric about the direction of its magnetic dipole moment, and decreases as the inverse cube of the distance from the object


Your supposed quote from Peratt is completely incorrect.

Let's repeat that last part:

"cube of the distance from the object"
cantdrive85
1 / 5 (7) Jun 05, 2013
Ha ha, wiki? This man was Alfvèn's protege. Alfvèn is largely responsible for the development of plasma physics as a discipline. This fact that he states is based on laboratory measurements, something relativists are incapable of doing. As stated earlier, your ignorance of the forces involved impinge upon your ability to understand the physics involved. I pulled the quote directly from his website, why don't your enlighten yourself and click the link I included. Here is his home page so you can start with the basics.
http://www.plasma...se.info/
GSwift7
5 / 5 (5) Jun 05, 2013
Ha ha, wiki?


You can find this information from thousands of places. I think the first time I learned it was probably in the 4H club electronics club, or maybe cub scouts. We did electronics stuff in both, so whatever.

If you don't like wiki, then do a google search, or hit a library, or email a professional engineer. This is a fundamental part of the theory you talk about all the time, and the fact that you don't understand it is laughable.

If Peratt has that on his web page, then he's a moron.
cantdrive85
1 / 5 (7) Jun 05, 2013
As you said, you learned it in 4-H or the scouts, from farmers and child molesters. Peratt learned it from a Nobel Laureate, it's quite plain to see who the moron is here!
cantdrive85
1 / 5 (7) Jun 05, 2013
BTW, electrodynamic orbits explain the observed phenomenon. And the orbits are NOT elliptical, they are in fact helical due the the relative movement of the galaxy.
Fleetfoot
5 / 5 (4) Jun 05, 2013
Your supposed quote from Peratt is completely incorrect.


Sadly, CD is quoting him accurately, it's near the bottom of the page just before the graphic:

http://www.plasma...ces.html

Of course, that then shows that CD's claim is false since an inverse square force is required to explain the orbits and his 'evidence' is a quote saying the force is just the inverse hence incapable of producing an orbit.
yyz
5 / 5 (3) Jun 06, 2013
"The closest of the S-stars, named S2..."

Just an update GSwift, a star with an even closer orbit (P=11.5yr) known as S0-102 has been discovered orbiting Sgr A*: http://en.wikiped...i/S0-102

The innermost region of the Milky Way Galaxy is a wild place indeed(no plasmoid needed).
cantdrive85
1 / 5 (6) Jun 06, 2013
Of course, that then shows that CD's claim is false since an inverse square force is required to explain the orbits and his 'evidence' is a quote saying the force is just the inverse hence incapable of producing an orbit.

Still clinging to a 2-D gravity only Universe. As pointed out, the orbits are in fact 3-D helical due to the motion of the galaxy, not 2-D elliptical. your premise is false, based on an out dated 19th century model. Electrodynamic interactions dominate in this dense plasma region.

The donut-shaped plasmoid of Sgr A*can be seen here;
http://www.astro....ld5.html

The complex network of galactic core filaments (electric currents) can be seen here, note the stars or arc mode plasma displays along those filaments.;
http://www.nrao.e...-p.shtml

And here you can see the coils of the electric motor (plasmoid) that drives the galaxy;
http://www.thunde...yway.htm

Fleetfoot
5 / 5 (4) Jun 06, 2013
.. the orbits are in fact 3-D helical due to the motion of the galaxy, not 2-D elliptical. your premise is false,


The orbits are ellipical and planar around Sag A*, that is an observational fact, not a premise.

Your problem is that a force related to the inverse of distance doesn't produce an orbit of any kind, helical or otherwise.

The donut-shaped plasmoid of Sgr A*can be seen here;
http://www.astro....ld7.html


Good presentation but you have the scale hopelessly wrong. Look at this page which zooms in on the gas:

http://www.astro....ics.html

In the bottom diagram you see a cloud of molecular gas.

Note the torus is about 100 arc-sec across.

Now look at this page which shows the stars:

http://www.astro....mbh.html

Note the scale is 0.1 arc-sec. Watch SO-19 as it whips round Sag A* and SO-2 complete a whole orbit.

Then look at slide 11, the object is smaller than 0.0001 arc-sec.
GSwift7
5 / 5 (5) Jun 06, 2013
Just an update GSwift, a star with an even closer orbit (P=11.5yr) known as S0-102 has been discovered


OOOOHHHH. That's cool. I didn't hear about that one. THANKS for the link yyz!

Man! You sure wouldn't want to be anywhere near that region of space. That's a LOT of BIG objects moving VERY fast in a small space.

I wonder where the Roche limit would be for Sgr-A? I wonder if it would be observable from here if any of the S-stars were already being slowly torn apart?

BTW, I'm done with CD. This stuff is obviously over his head and he's not interested in learning anything. That's a shame, because the mathematical beauty of Newtonian orbital mechanics is awe-inspiring.
antialias_physorg
3.9 / 5 (7) Jun 06, 2013
Man! You sure wouldn't want to be anywhere near that region of space. That's a LOT of BIG objects moving VERY fast in a small space.

Probably a lot of smaller objects, too. And with the frequent gamma ray burst and other nasties (like local supernovae) we can count ourselves pretty lucky that we're out here in the suburbs where it's nice an quiet by comparison.
barakn
5 / 5 (5) Jun 06, 2013
Cantdrive85 and Gswift7 were not discussing the same thing. Gswift7 was discussing the force of a magnetic field and cantdrive85 was word-dumping someone else's description of the force of an electric field, which definitely does follow a 1/r^2 rule. Cantdrive85 of course couldn't explain that because he doesn't actually know enough math or physics to able to know the difference between a magnetic and electric field.
Fleetfoot
5 / 5 (4) Jun 06, 2013
Cantdrive85 of course couldn't explain that because he doesn't actually know enough math or physics to able to know the difference between a magnetic and electric field.


Worse than that, this is from the page he was quoting in trying to explain Sag A*:

Thus immense plasma streams measured in megaparsecs, carrying galaxies and stars, can appear to be falling towards nothing when they are actually repelling.


He no concept of astronomical scales.
cantdrive85
1 / 5 (8) Jun 06, 2013
The orbits are ellipical and planar around Sag A*, that is an observational fact, not a premise.


Of course the Milky Way is stationary, and the Sun revolves around the Earth.

Gas dynamics of the galactic center? Once again applying "gas laws" to plasma. Fail!
Fleetfoot
5 / 5 (4) Jun 07, 2013
The orbits are ellipical and planar around Sag A*, that is an observational fact, not a premise.


Of course the Milky Way is stationary,


It's the same in Galilean relativity, relative to the barycentre, the orbit is elliptical and planar other than perturbations between the orbiting bodies.

and the Sun revolves around the Earth.


The Sun is 300 thousand times more massive than the Earth

Sag A* is 4 million times more massive than the stars that orbit it.

Gas dynamics of the galactic center? Once again applying "gas laws" to plasma. Fail!


You are nitpicking semantics to dodge your error, the structures you mention while trying to back up your claim that 'plasma' can explain the orbits of the S stars are more than a million times larger than the maximum possible size of whatever it is they are orbiting.

Your explanation fails by six orders of magnitude. It's equivalent to claiming the Moon orbits at a radius of 385m from the centre of the Earth.
cantdrive85
1 / 5 (7) Jun 07, 2013
It's the same in Galilean relativity, relative to the barycentre, the orbit is elliptical and planar other than perturbations between the orbiting bodies.

There's the rub, with an electrodynamically derived gravitational force, the relative movement of the galaxy is also considered and can be plotted as such. If the orbits of those stars were traced out through 3-D space over time they would reveal a helix. Sure from the our and core's POV it's elliptical, but the reality is the galaxy is moving along at quite a clip.

You are nitpicking semantics


I'm nitpicking the physics used, not the words. Ideal gas laws don't apply. I'm not claiming the "plasma is doing it" as much as the fact that the plasma itself is driven and modified by the EM forces involved.

Peratt's P-I-C simulations of interacting plasmoids not only predict the structure of galaxies, but also the chaotic phenomenon occurring at the galactic core.
Fleetfoot
5 / 5 (4) Jun 07, 2013
It's the same in Galilean relativity, relative to the barycentre, the orbit is elliptical and planar other than perturbations between the orbiting bodies.

There's the rub, with an electrodynamically derived gravitational force, the relative movement of the galaxy is also considered and can be plotted as such.


The relative motion motion is the same regardless of the cause of any forces, it is just what is observed.

If the orbits of those stars were traced out through 3-D space over time they would reveal a helix.


That depends entirely on your arbitrary choice of coordinate system.

Sure from the our and core's POV it's elliptical,


And it is the object at the core which is creating the orbit, hence if you want to know how the force varies as a function of distance, you plot it versus the distance from the core.

but the reality is the galaxy is moving along at quite a clip.


Relative to what? Nothing that is involved in producing the orbit.
Fleetfoot
5 / 5 (4) Jun 07, 2013
Ideal gas laws don't apply.


Of course not, nobody said they did. If you read the article, you'll find it discusses the effect of the magnetic fields creating the striations as you would expect. It also points out that the path of the torus is Keplerian, hence governed by gravity, not plasma effects.

I'm not claiming the "plasma is doing it" as much as the fact that the plasma itself is driven and modified by the EM forces involved.


Yes you are, look at your next sentence:

Peratt's P-I-C simulations of interacting plasmoids not only predict the structure of galaxies, but also the chaotic phenomenon occurring at the galactic core.


or previously:

BTW, electrodynamic orbits explain the observed phenomenon.


and

So the orbits of these stars is PREDICTED by PC


So go ahead, show how plasma effects can give the correct numerical predictions for the orbits of SO-2 and SO-19 as you have repeatedly claimed, it's "put up or shut up" time.