A whirling plane of satellite galaxies around Centaurus A challenges cold dark matter cosmology
Dwarf galaxies move in unexpected ways
Massive galaxies like our Milky Way are orbited by satellite dwarf galaxies. Standard cosmological simulations of galaxy formation predict that these satellites should move randomly around their host. Müller et al. examined the satellites of the nearby elliptical galaxy Centaurus A (see the Perspective by Boylan-Kolchin). They found that the satellites are distributed in a planar arrangement, and the members of the plane are orbiting in a coherent direction. This is inconsistent with more than 99% of comparable galaxies in simulations. Centaurus A, the Milky Way, and Andromeda all have highly statistically unlikely satellite systems. This observational evidence suggests that something is wrong with standard cosmological simulations.
Abstract
The Milky Way and Andromeda galaxies are each surrounded by a thin plane of satellite dwarf galaxies that may be corotating. Cosmological simulations predict that most satellite galaxy systems are close to isotropic with random motions, so those two well-studied systems are often interpreted as rare statistical outliers. We test this assumption using the kinematics of satellite galaxies around the Centaurus A galaxy. Our statistical analysis reveals evidence for corotation in a narrow plane: Of the 16 Centaurus A satellites with kinematic data, 14 follow a coherent velocity pattern aligned with the long axis of their spatial distribution. In standard cosmological simulations, <0.5% of Centaurus A–like systems show such behavior. Corotating satellite systems may be common in the universe, challenging small-scale structure formation in the prevailing cosmological paradigm.
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Supplementary Material
Summary
Materials and Methods
Supplementary Text
Figs. S1 and S2
Tables S1 and S2
Movie S1
Data Files S1 to S3
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References and Notes
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Information & Authors
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Published In
Science
Volume 359 • Issue 6375 • 2 February 2018
Pages: 534 - 537
History
Received: 24 June 2017
Accepted: 20 December 2017
Copyright
Copyright © 2018 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.
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http://dx.doi.org/10.13039/501100000923Australian Research Council:
http://dx.doi.org/10.13039/501100001711Swiss National Science Foundation:
RE: A whirling plane of satellite galaxies around Centaurus A challenges cold dark matter cosmology
To the editor, Science
The article by Muller, et al. (Science:359, pp. 534-537) shows the presence of a whirling plane of satellite galaxies around Centaurus A. They present arguments that challenge the standard ACDM cosmological model. This is exciting, though three of three analyzed cases in the context of a medical case report is only a clue that an alert investigator would recognize as the beginning point for further data gathering. Perhaps they have found evidence of new science, but more data is needed. If it was interesting enough, in medicine it might result in a multi-center trial. Since this potentially new science has to do with the basic nature of the universe, it seems interesting enough to me. An observing campaign by several large observatories in both to hemispheres and/or by the space telescope assets may be warranted.
Speculation as to what the finding may mean is a fun exercise.
The cosmic background microwave radiation COBE measurements heterogeneity and subsequent large-scale observed structure are explained by quantum mechanical variations in density in early eras after the primary singularity, the "big bang." Might there have been similar, initially quantum-scale variations in angular momentum persisting in the dark matter clouds that have manifested as observable galaxies (including satellite galaxies) formation? This might explain apparent aggregate average angular momentum (e.g. a whirling plane) in the condensed peripheral satellite galaxies of the Milky Way, Andromeda and now Centaurus A (3 of 3, as mentioned by the authors). Changes to the theory of gravity mentioned by the authors would not be required.
Based on Figure 1, the radius of the involved Centaurus A region is about 200 kpc. Assuming a Hydrogen Bohr radius of about 1 Angstrom as an approximate quantum-scale metric, my "back of the envelope" calculation suggests that the time horizon for the quantum fluctuation would be about 60 femtoseconds after the primary singularity.
The proposed observing campaign might find other interesting results, for example, how far back in time does conservation of angular momentum extend? Was the primary singularity isotropic or did it also have intrinsic angular momentum that might have pervasively persisted in dark matter clouds and their embedded visible matter condensations? If so, it might be observable as a statistically significant correlation in measured angular momentum vector direction. That would be interesting.
Henry W. Vea, MD, FACNM
Department of Imaging
Div. of Nuclear Medicine
Legacy Good Samaritan Hospital
Portland, OR 97219
office email: [email protected]
RE: Okona Tim
Honorable all!
As all we know, all kind of rules and existing fact of all kind properties in the universe almost 85% proved. The Big-Bang theory and the Dark matter of existence within the 15% liability. If every decade bring new discovery and brand new theories, the "Universe affected" persons, groups, start to looking for the answers. My opinion is, in the future, will almost 50% of real known rules, law, supposition radically change. One of most credible happening of the universe formation the "licking system". This system is assume, another "mirror space" existed somewhere another entire universe with almost same structure, and chemical, physical, magnetic, etc, conditions. When this Mirror Universe" died, shrink, and the endless energy and material "blow out" with enormous giant speed to another space area. This space area is now our universe area. BUT! When the realignment started, it was not able to recopy itself. Those faults, mistakes of rules ,laws create all new problems here. All ready existed galaxy, materials, planets, living planets was on the other side. Then finished. Like almost after 14 milliard years. Our beginning till now just half of this way. Our entire Universe will also shrink, and "blow out" to another present time absolutely empty endless space, with the same problems. Of course this theory in details need it days to explain, but why always discovered new rule, laws, events? Because the "Mirrors effect" anomaly is the engine of it, and the correction of the known present is very poor, and deficient.
Thank you for listening. Mr. Okana
Science of the futureRE: Possible solution of presented problem?
Great observation!
I think, that such an arrangements results just from rules of relativity, in particular limitation imposed on speed of gravitational interactions. On large scales, and this is the case, moving center of mass is "somewhere else" in the direction of its movement. Thus, in the course of millenia, orbits of satellite companions may evolve due to the non-centrality attracitve force, thus direction of angular momentum vector changes until it gets perpendicular to the direction of the galaxy trajectory.
Moreover, the same rule should apply to the galaxy itself what in turn means, that galaxy disc should be aligned parallelly along its trajectory.
Conclusions:
1) must check, if galaxy planes are aligned parallelly with its trajectory,
2) must perform large numerical simulations of presented alignment scenario.
3) thus standard model may be rescued.
With best regards,
Janusz Opiła, Ph.D.
Scopus Author ID: 6508213752
ResearcherID is: S-1948-2016