Related papers: The major merger origin of the Andromeda II kinema…
Warps are suspected in disks around massive compact objects. However, the proposed warping source -- non-axisymmetric radiation pressure -- does not apply to white dwarfs. In this letter we report the first Smoothed Particle Hydrodynamic…
The origin of the irregular satellites of the giant planets has been long debated since their discovery. Their dynamical features argue against an in-situ formation suggesting they are captured bodies, yet there is no global consensus on…
We use the APOSTLE Local Group (LG) cosmological hydro-simulations to examine the properties of "backsplash" galaxies, i.e, dwarfs which were within the virial boundaries of the Milky Way (MW) or M31 in the past, but are today outside their…
Two-dimensional integral field surveys such as ATLAS^3D are producing rich observational data sets yielding insights into galaxy formation. These new kinematic observations have highlighted the need to understand the evolutionary mechanisms…
In this paper, we examine whether tidal forces exerted by the Galaxy or M31 have an influence on the Local Group dwarf spheroidal galaxies (dSphs) which are their companions. We focus on the surface brightness profiles of the dSphs,…
We present results from the first numerical analysis to support the hypothesis, first proposed in Coleman et al. (2004), that the Fornax dwarf galaxy was formed from the minor merging of two dwarfs about 2 Gyr ago. Using orbits for the…
We report the discovery of a giant stellar tidal stream in the halo of NGC 4631, a nearby edge-on spiral galaxy interacting with the spiral NGC 4656, in deep images taken with a 40-cm aperture robotic telescope. The stream has two…
Using a high resolution N-body simulation of a two-component dwarf galaxy orbiting in the potential of the Milky Way, we study two effects that lead to significant biases in mass estimates of dwarf spheroidal galaxies. Both are due to the…
We present the discovery of an inhomogenous, low-surface brightness, extended disk-like structure around the Andromeda galaxy (M31) based on a large kinematic survey of more than 2800 stars with the Keck/DEIMOS spectrograph. The stellar…
We present 3D hydrodynamic simulations aimed at studying the dynamical and chemical evolution of the interstellar medium in dwarf spheroidal galaxies. This evolution is driven by the explosions of Type II and Type Ia supernovae, whose…
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…
Surface photometry of the M31 satellites M32 and NGC 205 is compared to numerical simulations of satellite destruction to constrain orbital parameters and the interaction history of the M31 subgroup. Our analysis reveals the following…
We present an extragalactic perspective of an extended stellar tidal stream wrapping around the edge-on, spiral galaxy NGC 5907. Our deep images reveal for the first time a large scale complex of arcing loops that is an excellent example of…
In the modified dynamics (MOND) the inner workings of dwarf satellites can be greatly affected by their mother galaxy-over and beyond its tidal effects. Because of MOND's nonlinearity a system's internal dynamics can be altered by an…
Dimorphos' oblate shape challenges formation models. Landslides on Didymos, induced by YORP effect, probably created a debris ring from which Dimorphos would have formed. Nonetheless, ring-derived satellites typically form with a prolate…
It has been proposed that mergers induce starbursts and lead to important morphological changes in galaxies. Most studies so far have focused on large galaxies, but dwarfs might also experience such events, since the halo mass function is…
The tidal stirring model envisions the formation of dwarf spheroidal (dSph) galaxies in the Local Group via the tidal interaction of disky dwarf systems with a larger host galaxy like the Milky Way. These progenitor disks are embedded in…
The impact of the dynamical state of gas-rich satellite galaxies at the early moments of their infall into their host systems and the relation to their quenching process are not completely understood at the low-mass regime. Two such nearby…
We employ recently published measurements of the velocity dispersions in the newly discovered dwarf satellite galaxies of Andromeda to test our previously published predictions of this quantity. The data are in good agreement with our…
We present a dynamical measurement of the tangential motion of the Andromeda system, the ensemble consisting of the Andromeda Galaxy (M31) and its satellites. The system is modelled as a structure with cosmologically-motivated velocity…