Distant galaxy group contradicts common cosmological models, simulations

Distant galaxy group contradicts common cosmological models, simulations
Centaurus A, an elliptical galaxy 13 million light-years from Earth, hosts a group of dwarf satellite galaxies co-rotating in a narrow disk, a distribution not predicted by dark-matter-influenced cosmological models. Credit: Christian Wolf and the SkyMapper team / Australian National University

An international team of astronomers has determined that Centaurus A, a massive elliptical galaxy 13 million light-years from Earth, is accompanied by a number of dwarf satellite galaxies orbiting the main body in a narrow disk. In a paper published today in Science, the researchers note that this is the first time such a galactic arrangement has been observed outside the Local Group, home to the Milky Way.

"The significance of this finding is that it calls into question the validity of certain cosmological models and simulations as explanations for the distribution of host and in the universe," said co-author Marcel Pawlowski, a Hubble Fellow in the Department of Physics & Astronomy at the University of California, Irvine.

He said that under the lambda cold dark matter model, smaller systems of stars should be more or less randomly scattered around their anchoring galaxies and should move in all directions. Yet Centaurus A is the third documented example, behind the Milky Way and Andromeda, of a "vast polar structure" in which satellite dwarves co-rotate around a central galactic mass in what Pawlowski calls "preferentially oriented alignment."

The difficulty of studying the movements of dwarf satellites around their hosts varies according to the target galaxy group. It's relatively easy for the Milky Way. "You get proper motions," Pawlowski said. "You take a picture now, wait three years or more, and then take another picture to see how the stars have moved; that gives you the tangential velocity."

Using this technique, scientists have measurements for 11 Milky Way satellite galaxies, eight of which are orbiting in a tight disk perpendicular to the spiral galaxy's plane. There are probably other satellites in the system that can't be seen from Earth because they're blocked by the Milky Way's dusty disk.

The Centaurus A galaxy system. Credit: Marcel Pawlowski / UCI

Andromeda provides observers on Earth a view of the full distribution of satellites around the galaxy's sprawling spiral. An earlier study found 27 dwarf galaxies, 15 arranged in a narrow plane. And Andromeda offers another advantage, according to Pawlowski: "Because you see the galaxy almost edge-on, you can look at the line-of-sight velocities of its satellites to see the ones that are approaching and those that are receding, so it very clearly presents as a rotating disk."

Centaurus A is much farther away, and its satellite companions are faint, making it more difficult to accurately measure distances and velocities to determine movements and distributions. But "sleeping in the archives," Pawlowski said, were data on 16 of Centaurus A's satellites.

"We could do the same game as with Andromeda, where we look at the line-of-sight velocities," he said. "And again we see that half of them are red-shifted, meaning they are receding from us, and the other half are blue-shifted, which tells us they are approaching."

The researchers were able to demonstrate that 14 of the 16 Centaurus A satellite follow a common motion pattern and rotate along the plane around the main galaxy - contradicting frequently used cosmological models and simulations suggesting that only about 0.5 percent of galaxy systems in the nearby universe should exhibit this pattern.

"So this means that we are missing something," Pawlowski said. "Either the simulations lack some important ingredient, or the underlying model is wrong. This research may be seen as support for looking into alternative models."

Explore further

Hubble displays a dwarf spiral galaxy

More information: O. Müller at Universität Basel in Basel, Switzerland el al., "A whirling plane of satellite galaxies around Centaurus A challenges cold dark matter cosmology," Science (2018). science.sciencemag.org/cgi/doi … 1126/science.aao1858
Journal information: Science

Citation: Distant galaxy group contradicts common cosmological models, simulations (2018, February 1) retrieved 14 October 2019 from https://phys.org/news/2018-02-distant-galaxy-group-contradicts-common.html
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Feb 01, 2018
The researchers were able to demonstrate that 14 of the 16 Centaurus A satellite galaxies follow a common motion pattern and rotate along the plane around the main galaxy - contradicting frequently used cosmological models and simulations suggesting that only about 0.5 percent of satellite galaxy systems in the nearby universe should exhibit this pattern.

It sure would be nice if they provided some quantitative basis for claiming this violation.

For instance, in what way does a single galaxy and its satellites represent MORE THAN 0.5 percent of the nearby universe?

It can be very difficult to determine what is bad science and what is bad "journalism". In this case, one has to assume it is the latter. It's too bad that the University of California has such low journalistic standards, allowing such an extraordinary claim without explanation.

Feb 01, 2018
It sure would be nice if they provided some quantitative basis for claiming this violation.

For instance, in what way does a single galaxy and its satellites represent MORE THAN 0.5 percent of the nearby universe?

I thought the point was that they added a third system to the total catalog of such systems that have been mapped this way, and now 3 out of 3 follow this pattern. Which would be really unlikely if only 0.5 percent of the universe behaved that way.

For me, I think it was already odd that they'd look at the only two they could see before and say, "Oh, those are the odd ducks, it's only because they're the closest ones, the rest of the universe is completely different." Some kind of reverse geocentrism. Flat Earth LCDM.

Feb 01, 2018
"There should be pure chaos and not order," said Müller. "To find everywhere we look this extreme order where we expect disorder—this is strange."


The swarming dwarfs are simply daughters of the parent, having been ejected therefrom. They start near the core as star clusters, being ejected therefrom and growing internally all the while. By the time the faster ones exit the galaxy, they have grown into dwarf galaxies themselves. Since they are born and ejected from the core in from a similar process, they tend to align preferentially in a disk.

We see the satellite galaxies are in a huge disk and moving in the same direction within this disk, like the planets in our solar system moving in a thin plane in one direction around the sun. That's unexpected and could be a real problem."


Feb 01, 2018
Considering the moment of creation was 13.8billion years ago, Centaurus A is 13.05billion years old and stars are surrounding Centaurus A all round for 100s of millions of light years bringing the distance of the stars extremely close to the 13.8billion year old bigbang.

Feb 01, 2018
The models are based on a dark matter halo around galaxies which would result in random distribution and movement of dwarf satellite galaxies. Another indication that the dark matter hypotheses are not representative of what we observe.

Feb 01, 2018
Part 1/3]
The model I have tentatively (and unofficially) proposed does not have these problems. Put simply there are two ways to characterise the rotation of galaxies problem:
a) Consider the motion of the inner stars to predict the mass of the central hub. The mass so calculated is insufficient to hold the outer stars in their orbit (they are orbiting too fast for the calculated mass). To resolve this paradox Dark Matter is proposed, distributed throughout the galaxy.

b) Consider the motion of the OUTER stars to predict the mass of the inner hub OR the inner hub PLUS Dark Matter. The inner stars (without Dark Matter) are orbiting the central hub too slowly. An attenuation of of the gravitational force/spacetime curvature around massive objects must be proposed to resolve the paradox.

Feb 01, 2018
Part 2/3]
For (b) we may consider that the inward velocity of an infalling particle reaches and exceeds the speed of light as it passes over the event horizon BUT NOT if the addition of velocities is applied, an inconsistency in current theory. Second, the escape velocity (escape to infinity) is exactly equal to the terminal velocity of an infalling particle (from infinity) which makes the escape velocity greater than c, but if we apply the addition of velocities (consider the instantaneous speed of the infalling particle at any point and then apply acceleration to greater speed using addition of velocities) then the two numbers no longer match.

Feb 01, 2018
Part 3/3]
By considering an 'Addition of Masses' equation, a mirror of the 'Addition of Velocities', we consider the progressive increase in escape velocity from a point above a single concentrated mass as more mass is added, the equation showing that the escape velocity never reaches c and so no event horizon (or singularity) ever form and the shallower curvature close to super-massive objects explains the rotation of galaxies and removes the need for Dark Matter generally, solves the information paradox for Black Holes and returns us to a more sensible universe

It also accounts for the solves the problem expressed in the above article

Feb 01, 2018
Hang on, if the Galaxy and it's closest neighbour, the Andromeda galaxy both exhibit this model then wouldn't that automatically mean it's fairly common? Analogous to, if we found life on another planet or moon in our solar system then we would not conclude that life is exceedingly rare and this is a fantastic coincidence, we'd immediately jump to the conclusion that life must be commonplace.

Feb 02, 2018
Typical galactic local groups
The Milkyway at 13.6billion yrs old is in its local group of galaxies containing 54 mostly dwarf galaxies including M31 and its centre of mass is between our Milky Way and Andromeda galaxy. Centaurus A, at 10 to 16million lys has its own local group containing dwarf galaxies, so far 16 observable dwarf galaxies, is there something unique concerning our local group as a typical galactic local group.

Feb 02, 2018
Of the 14 dwarf galaxies observed they are all in Synchronised unidirectional orbits, where as the filaments of dark matter pervading the vacuum allows large galaxies to grow with dwarf galaxies drawn along the lines of the filamentary darkmatter causing randomised orbits. The Milkyway's local group in synchronised orbits, are immersed in the same lines of the filamentary darkmatter. Whatever darkmatter gravitational effects our local group are experiencing, Centaurus A is experiencing the same darkmatter gravitational effects or is the implication that there are variations in the cosmic darkmatter model that applies to different local groups and it's just that Centaurus A is following the same variation as our local group

Feb 02, 2018
Per Wikipedia, "common cosmological models" were tentative at best even before this news:

" ...it is proposed that matter started out in these "smaller" clumps (mass on the order of globular clusters), and then many of these clumps merged to form galaxies,[4] which then were drawn by gravitation to form galaxy clusters. This still results in disk-like distributions of baryonic matter with dark matter forming the halo for all the same reasons as in the top-down theory. Models using this sort of process predict more small galaxies than large ones, which matches observations.

Astronomers do not currently know what process stops the contraction. In fact, theories of disk galaxy formation are not successful at producing the rotation speed and size of disk galaxies."

Feb 02, 2018
This observational evidence further supports Halton Arp's conclusions that dwarf galaxies are ejected from their "parent" galaxies as AGN's and then fall into orbit around the parent galaxies.

Feb 03, 2018
Polarity or anisotropy are among the distinguishing characteristics of the underlying composition of the universe. So of course any model that would assume otherwise is on its face inconsistent. See for example the birefringent property of the electromagnetic propagation in the universe. https://arxiv.org...2579.pdf https://thingumbo...-in.html

Feb 03, 2018
See also "Mysterious Dance of Dwarfs May Force a Cosmic Rethink," Physorg article July 21, 2014. Immense plane of dwarf galaxies orbiting Andromeda.

Feb 03, 2018
There is an "odd sympathy" among these dwarf satellite galaxies. That's the phrase used by Christiann Huygens.circa 1660 to describe the self-organization of two of his pendulum clocks. The periodic oscillations of their pendula were precisely anti-phase to each other.

Half blue shift, half red shift.

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