Orbits of 47 Dwarf Satellite Galaxies of the Milky Way in Three Models of the Gravitational Potential with Different Masses

TL;DR

This study analyzes the orbits of 47 dwarf satellite galaxies of the Milky Way using three different models of the Galaxy's gravitational potential, revealing how model assumptions affect orbital characteristics and galaxy associations.

Contribution

It provides a comparative analysis of dwarf galaxy orbits across three Galactic potential models, highlighting the impact of mass assumptions on gravitational binding.

Findings

Identified dwarf galaxies not gravitationally bound to the Milky Way in each model.

Compared orbital parameters across models to assess sensitivity to Galactic mass.

Reconstructed 13.5 Gyr orbital histories for all satellites.

Abstract

The analysis of the orbits of 47 dwarf satellite galaxies of the Milky Way, built using three models of the Galactic gravitational potential with different masses, is presented. The models of the Galactic potential were chosen based on the analysis of a large number of the Galaxy mass estimates known from the literature. The astrometric data needed for calculation of the initial positions and velocities (6D phase space) of the dwarf galaxies are also taken from the literature, where the average proper motions were determined on the basis of the data from the Gaia DR2 Catalog. We present the orbits and their properties of all 47 dwarf galaxies obtained by integration for 13.5 Gyr backward in all three models of the Galactic potential and give a comparison of the orbital parameters. For each model of the Galactic potential we have identified dwarf galaxies that are not connected gravitationally with the Milky Way.