Related papers: The Planes of Satellite Galaxies Problem, Suggeste…
The "plane of satellites problem" describes the arrangement of the Milky Way's 11 brightest satellite galaxies in a remarkably thin plane, possibly supported by rotation. This is in apparent contradiction to the standard cosmological model,…
The planar distributions of satellite galaxies around the Milky Way and Andromeda have been extensively studied as potential challenges to the standard cosmological model. Using the Sloan Digital Sky Survey and the Millennium simulation we…
The Milky Way, the Andromeda galaxy, and Centaurus A host flattened distributions of satellite galaxies which exhibits coherent velocity trends indicative of rotation. Comparably extreme satellite structures are very rare in cosmological…
A large fraction of the dwarf satellites orbiting the Andromeda galaxy are surprisingly aligned in a thin, extended and apparently kinematically coherent planar structure. Such a structure is not easily found in simulations based on the…
Since the mid 70ies it is known that the dwarf galaxies around the Milky Way are arranged in a thin, polar structure. The arrangement and motion within this structure has been identified as a severe challenge to the standard model of…
The detection of planar structures within the satellite systems of both the Milky Way (MW) and Andromeda (M31) has been reported as being in stark contradiction to the predictions of the standard cosmological model ($\Lambda$CDM). Given the…
Recent observational studies have demonstrated that the majority of satellite galaxies tend to orbit their hosts on highly flattened, vast, possibly co-rotating planes. Two nearly parallel planes of satellites have been confirmed around the…
Half of the satellite galaxies of Andromeda form a narrow plane termed the Great Plane of Andromeda (GPoA), and their line-of-sight velocities display correlation reminiscent of a rotating structure. Recently reported first proper motion…
Driven by increasingly complete observational knowledge of systems of satellite galaxies, mutual spatial alignments and relations in velocities among satellites belonging to a common host have become a productive field of research. Numerous…
It has been suggested that the satellite galaxies of the Milky Way reside in a highly-flattened, kinematically-coherent plane called Disk of Satellites (DoS). The origin of the DoS, however, has been hotly debated, and a number of…
The distribution of smaller satellite galaxies around large central galaxies has attracted attention because peculiar spatial and kinematic configurations have been detected in some systems. A particularly striking example of such behavior…
Recent observations have shown that the majority of the Andromeda galaxy's satellites are aligned in a thin plane. On the theoretical side it has been proposed that galaxies acquire their gas via cold streams. In addition, numerical…
We examine the spatial distribution and orbital pole correlations of satellites in a suite of zoom-in high-resolution dissipationless simulations of Miky Way (MW) sized haloes. We use the measured distribution to estimate the incidence of…
Recent work has shown that both the Milky Way and the Andromeda galaxies possess the unexpected property that their dwarf satellite galaxies are aligned in thin and kinematically coherent planar structures. It is now important to evaluate…
Sub-halos in dark-matter-based cosmological simulations tend to be distributed approximately isotropically around their host. The existence of highly flattened, co-orbiting planes of satellite galaxies has therefore been identified as a…
The recently discovered vast thin plane of dwarf satellites orbiting the Andromeda Galaxy (M31) adds to the mystery of the small scale distribution of the Local Group's galaxy population. Such well defined planar structures are apparently…
The existence of planes of satellite galaxies has been identified as a long-standing challenge to $\Lambda$CDM cosmology, due to the rarity of satellite systems in cosmological simulations that are as extremely flattened and as strongly…
Planes of satellites are observed around many galaxies. However, these observations are still considered a point of tension for the $\Lambda$CDM paradigm. We use the fully hydrodynamical cosmological $\Lambda$CDM state-of-the-art simulation…
The Milky Way and Andromeda galaxy are each surrounded by a thin plane of satellite galaxies that may be corotating. Cosmological simulations predict that most satellite galaxy systems are close to isotropic with random motions, so those…
We compute the locations of satellite galaxies with respect to their hosts using the Lambda-CDM GIF simulation. If the major axes of the hosts' images are perfectly aligned with the major axes of their projected mass, the satellites are…