Related papers: Proper Motions in the Andromeda Subgroup
We present the line-of-sight (LOS) velocities for 13 distant main sequence Milky Way halo stars with published proper motions. The proper motions were measured using long baseline (5-7 years) multi-epoch HST/ACS photometry, and the LOS…
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…
Neutral hydrogen clouds are found in the Milky Way and Andromeda halo both as large complexes and smaller isolated clouds. Here we present a search for Hi clouds in the halo of M33, the third spiral galaxy of the Local Group. We have used…
We compare the number of detected 22 GHz H2O masers in the Local Group galaxies M31, M33, NGC6822, IC10, IC1613, DDO187, GR8, NGC185, and the Magellanic Clouds with the water maser population of the Milky Way. To accomplish this we searched…
The Local Group (LG) consists of two giant spiral galaxies, the Milky Way (MW) and Andromeda (M31), and several smaller galaxies. The MW and M31 are approaching each other at a radial velocity of about $-109\,$km\,s$^{-1}$. Observational…
Our Galaxy, Andromeda and their companion dwarf galaxies form the Local Group. Most of the mass in and around it is believed to be dark matter rather than gas or stars, so its distribution must be inferred from the effect of gravity on the…
From high resolution cosmological simulations of the Local Group in realistic environment, namely HESTIA simulations, we study the position and kinematic deviations that may arise between the disc of a Milky Way (or Andromeda)-like galaxy…
The kinematics of galaxies with 10 megaparsecs (10 Mpc) of the Milky Way is investigated using published distances and radial velocities. With respect to the average Hubble flow (isotropic or simple anisotropic), there is NO systematic…
We analyze the velocity field of peripheral members of the Local Group. The Hubble flow at distances from 400 to 1400~kpc, formed by 7 of 11 nearby galaxies, is characterized by an extremely small line-of-sight velocity dispersion of 15…
Space observatories like the Hubble Space Telescope and Gaia are providing unprecedented 6D phase space information of satellite galaxies. Such measurements can shed light on the structure and assembly history of the Local Group, but…
Our nearest large cosmological neighbour, the Andromeda galaxy (M31), is a dynamical system, and an accurate measurement of its total mass is central to our understanding of its assembly history, the life-cycles of its satellite galaxies,…
The satellite galaxies of the Local Group provide us with an important probe of galaxy formation, evolution, and cosmology. The two large spirals that dominate this group -- the Milky Way and Andromeda -- are each host to tens of…
We present the first proper motion measurements for the galaxy M31. We obtained new V-band imaging data with the HST ACS/WFC and WFC3/UVIS of a spheroid field near the minor axis, an outer disk field along the major axis, and a field on the…
We present a spectroscopic survey of the giant stellar stream found in the halo of the Andromeda galaxy. Taken with the DEIMOS multi-object spectrograph on the Keck2 telescope, these data display a narrow velocity dispersion of 11+/-3 km/s,…
We use updated data on distances and velocities of galaxies in the proximity of the Local Group (LG) in order to establish properties of the local Hubble flow. For 30 neighbouring galaxies with distances 0.7 < D_LG < 3.0 Mpc, the Local flow…
A solution is presented for the past motions of the Magellanic Clouds, the Milky Way galaxy, and M31, fitted to the measured velocities of the Clouds and M31, under some simplifying assumptions. The galaxies are modeled as isolated bodies…
Based on long baseline (5-7 years) multi-epoch HST/ACS photometry, used previously to measure the proper motion of M31, we present the proper motions (PMs) of 13 main-sequence Milky Way halo stars. The sample lies at an average distance of…
The peculiar radial velocities of eight clusters of galaxies, as determined from a variety of distance indicators, are consistent with a bulk flow not greatly different in direction and magnitude from the velocity vector of the Local Group…
We present the first internal motion measurement of the 6.7-GHz methanol maser within S269, a small HII region in the outer Galaxy, which was carried out in 2006 and 2011 using the Japanese VLBI Network (JVN). Several maser groups and weak…
In the rest frame of the Local Group (LG), the total momentum of the Milky Way (MW) and Andromeda (M31) should balance to zero. We use this fact to constrain new solutions for the solar motion with respect to the LG centre-of-mass, the…