The mass of our Milky Way

Abstract

We perform an extensive review of the numerous studies and methods used to determine the total mass of the Milky Way. We group the various methods into seven broad classes, including: i) estimating Galactic escape velocity using high velocity objects; ii) measuring the rotation curve through terminal and circular velocities; iii) modeling halo stars, globular clusters and satellite galaxies with the Spherical Jeans equation and iv) with phase-space distribution functions; v) simulating and modeling the dynamics of stellar streams and their progenitors; vi) modeling the motion of the Milky Way, M31 and other distant satellites under the framework of Local Group timing argument; and vii) measurements made by linking the brightest Galactic satellites to their counterparts in simulations. For each class of methods, we introduce their theoretical and observational background, the method itself, the sample of available tracer objects, model assumptions, uncertainties, limits and the corresponding measurements that have been achieved in the past. Both the measured total masses within the radial range probed by tracer objects and the extrapolated virial masses are discussed and quoted. We also discuss the role of modern numerical simulations in terms of helping to validate model assumptions, understanding systematic uncertainties and calibrating the measurements. While measurements in the last two decades show a factor of two scatters, recent measurements using \textit{Gaia} DR2 data are approaching a higher precision. We end with a detailed discussion of future developments, especially as the size and quality of the observational data will increase tremendously with current and future surveys. In such cases, the systematic uncertainties will be dominant and thus will necessitate a much more rigorous testing and characterization of the various mass determination methods.

invited review published by Science China Physics, Mechanics & Astronomy

References in corpus (108)

• The EAGLE project: Simulating the evolution and assembly of galaxies and their environments
• Introducing the Illustris Project: Simulating the coevolution of dark and visible matter in the Universe
• Gaia Data Release 1. Summary of the astrometric, photometric, and survey properties
• galpy: A Python Library for Galactic Dynamics
• The EAGLE simulations of galaxy formation: calibration of subgrid physics and model variations
• Too big to fail? The puzzling darkness of massive Milky Way subhaloes
• Properties of galaxies reproduced by a hydrodynamic simulation
• The mass distribution and gravitational potential of the Milky Way
• Introducing the Illustris Project: the evolution of galaxy populations across cosmic time
• Trigonometric Parallaxes of Massive Star Forming Regions: VI. Galactic Structure, Fundamental Parameters and Non-Circular Motions
• The Radial Velocity Experiment (RAVE): first data release
• The Milky Way's Circular Velocity Curve to 60 kpc and an Estimate of the Dark Matter Halo Mass from Kinematics of ~2400 SDSS Blue Horizontal Branch Stars
• The Two Young Star Disks in the Central Parsec of the Galaxy: Properties, Dynamics and Formation
• The RAVE Survey: Constraining the Local Galactic Escape Speed
• The COS-Halos Survey: Physical Conditions and Baryonic Mass in the Low-Redshift Circumgalactic Medium
• Are the Magellanic Clouds on their First Passage about the Milky Way?
• The Radial Velocity Experiment (RAVE): Fifth Data Release
• The accretion origin of the Milky Way's stellar halo
• The Milky Way's circular velocity curve between 4 and 14 kpc from APOGEE data
• Detection of a 63 Degree Cold Stellar Stream in the Sloan Digital Sky Survey
• On the local dark matter density
• An Orphan in the "Field of Streams"
• Is the SMC Bound to the LMC? The HST Proper Motion of the SMC
• The M31 Velocity Vector. II. Radial Orbit Towards the Milky Way and Implied Local Group Mass
• Constraining the Milky Way's Hot Gas Halo with OVII and OVII Emission Lines
• "Skinny Milky Way, Please", says Sagittarius
• The Origin of the Bifurcation in the Sagittarius Stream
• Detection of a 60 Degree-Long Dwarf Galaxy Debris Stream
• The GALAH Survey: Observational Overview and Gaia DR1 companion
• On the Shoulders of Giants: Properties of the Stellar Halo and the Milky Way Mass Distribution
• Constraining the Galaxy's dark halo with RAVE stars
• Globular Cluster Streams as Galactic High-Precision Scales - The Poster Child Palomar 5
• Constraints on the Dark Matter Particle Mass from the Number of Milky Way Satellites
• Small Dwarf Galaxies Within Larger Dwarfs: Why Some Are Luminous While Most Go Dark
• Kinematics of the stellar halo and the mass distribution of the Milky Way using BHB stars
• Galactic masers and the Milky Way circular velocity
• The shape of the inner Milky Way halo from observations of the Pal 5 and GD-1 stellar streams
• The LAMOST Stellar Parameter Pipeline at Peking University --- LSP3
• A new determination of the local dark matter density from the kinematics of K dwarfs
• The Mass Profile of the Galaxy to 80 kpc
• Hypervelocity Stars: Predicting the Spectrum of Ejection Velocities
• The velocity dispersion and mass profile of the Milky Way
• Discovery of a New, Polar-Orbiting Debris Stream in the Milky Way Stellar Halo
• A 22 Degree Tidal Tail for Palomar 5
• The Space Motion of Leo I: Hubble Space Telescope Proper Motion and Implied Orbit
• The M31 Velocity Vector. I. Hubble Space Telescope Proper Motion Measurements
• Orbits of Massive Satellite Galaxies: I. A Close Look at the Large Magellanic Cloud and a New Orbital History for M33
• A dynamical model of the local cosmic expansion
• Halo Substructure in the SDSS-Gaia Catalogue : Streams and Clumps
• The local high velocity tail and the Galactic escape speed
• The M31 Velocity Vector. III. Future Milky Way-M31-M33 Orbital Evolution, Merging, and Fate of the Sun
• Satellites of Simulated Galaxies: survival, merging, and their relation to the dark and stellar halos
• Proper Motions of Dwarf Spheroidal Galaxies from Hubble Space Telescope Imaging. IV: Measurement for Sculptor
• Hypervelocity Stars: From the Galactic Center to the Halo
• Halo Star Streams in the Solar Neighborhood
• Orbital decomposition of CALIFA spiral galaxies
• Dynamics of the Magellanic Clouds in a LCDM Universe
• The Next Generation Virgo Cluster Survey. VI. The Kinematics of Ultra-compact Dwarfs and Globular Clusters in M87
• The PAndAS Field of Streams: stellar structures in the Milky Way halo toward Andromeda and Triangulum
• Extended distribution functions for our Galaxy
• Milky Way Mass and Potential Recovery Using Tidal Streams in a Realistic Halo
• Dipping Our Toes in the Water: First Models of GD-1 as a Stream
• Discovery of a cold stellar stream in the ATLAS DR1 data
• Open Clusters as Galactic Disk Tracers: I. Project Motivation, Cluster Membership and Bulk Three-Dimensional Kinematics
• The Milky Way Rotation Curve and its Vertical Derivatives Inside the Solar Circle
• Action-based distribution functions for spheroidal galaxy components
• Hypervelocity Stars III. The Space Density and Ejection History of Main Sequence Stars from the Galactic Center
• The distribution function of dark matter in massive haloes
• Reflex motion in the Milky Way stellar halo resulting from the Large Magellanic Cloud infall
• Milky Way mass constraints from the Galactic satellite gap
• Balancing mass and momentum in the Local Group
• Kinematics of hypervelocity stars in the triaxial halo of the Milky Way
• Hypervelocity stars and the environment of Sgr A*
• Production of Hypervelocity Stars through Encounters with Stellar-Mass Black Holes in the Galactic Centre
• Predicted Extension of the Sagittarius Stream to the Milky Way Virial Radius
• Serendipitous Discovery of a Thin Stellar Stream near the Galactic Bulge in the Pan-STARRS1 3Pi Survey
• Inferring the gravitational potential of the Milky Way with a few precisely measured stars
• Bayesian Mass Estimates of the Milky Way II: The dark and light sides of parameter assumptions
• The effects of dynamical substructure on Milky Way mass estimates from the high velocity tail of the local stellar halo
• Hypervelocity Collisions of Binary Stars at the Galactic Centre
• A new spin on disks of satellite galaxies
• The Milky Way Tomography with SDSS. V. Mapping the Dark Matter Halo
• Evolution of galactic planes of satellites in the EAGLE simulation
• Characterizing stellar halo populations II: The age gradient in blue horizontal-branch stars
• Creating mock catalogues of stellar haloes from cosmological simulations
• A fast algorithm for estimating actions in triaxial potentials
• Subhalo statistics of galactic halos: beyond the resolution limit
• A skewer survey of the Galactic halo from deep CFHT and INT images
• Made-to-Measure Dark Matter Haloes, Elliptical Galaxies and Dwarf Galaxies in Action Coordinates
• Modeling the gravitational potential of a cosmological dark matter halo with stellar streams
• Proper Motion of the Leo II Dwarf Galaxy Based On Hubble Space Telescope Imaging
• Bayesian Mass Estimates of the Milky Way: including measurement uncertainties with hierarchical Bayes
• Fitting orbits to tidal streams with proper motions
• The stellar halo of the Milky Way traced by blue horizontal-branch stars in the Subaru Hyper Suprime-Cam Survey
• Hubble Space Telescope Proper Motions along the Sagittarius Stream: I. Observations and Results for Stars in Four Fields
• Two New Halo Debris Streams in the Sloan Digital Sky Survey
• $\text{galkin}$: a new compilation of the Milky Way rotation curve data
• The Milky Way's circular velocity curve and its constraint on the Galactic mass with RR Lyrae stars
• Determination of Dark Matter Halo Mass from Dynamics of Satellite Galaxies
• A dynamics-free lower bound on the mass of our galaxy
• Hamiltonians of Spherically Symmetric, Scale-Free Galaxies in Action-Angle Coordinates
• Modified Virial Formulae and the Theory of Mass Estimators
• A Lower Limit on the Mass of Our Galaxy from the H3 Survey
• A Versatile and Accurate Method for Halo Mass Determination from Phase-Space Distribution of Satellite Galaxies
• Local Group Analogs in $\Lambda$CDM cosmological simulations
• Statistical properties of substructures around Milky Way-sized haloes and their implications for the formation of stellar streams
• Jeans that fit: weighing the mass of the Milky Way analogues in the $\Lambda \mathrm{CDM}$ universe
• Accurate Masses for Navarro-Frenk-White Dark Matter Haloes

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• Gaia early DR3 systemic motions of Local Group dwarf galaxies and orbital properties with a massive Large Magellanic Cloud
• Overview of the DESI Milky Way Survey
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• Measuring the Milky Way mass distribution in the presence of the LMC
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• The Circular Velocity Curve of the Milky Way from 5 to 25 kpc using luminous red giant branch star
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• Equilibrium models of the Milky Way mass are biased high by the LMC
• The effect of the deforming dark matter haloes of the Milky Way and the Large Magellanic Cloud on the Orphan-Chenab stream
• A robust estimate of the Milky Way mass from rotation curve data
• The Mass of the Milky Way from the H3 Survey
• Milky Way total Mass derived by Rotation Curve and Globular Cluster kinematics from Gaia EDR3
• Milky Way Mass with K Giants and BHB Stars Using LAMOST, SDSS/SEGUE, and Gaia: 3D Spherical Jeans Equation and Tracer Mass Estimator
• The Most Metal-poor Stars in the Magellanic Clouds are $r$-process Enhanced
• Action-based distribution function modelling for constraining the shape of the Galactic dark matter halo
• Probing Dark Matter Self-interaction with Ultra-faint Dwarf Galaxies
• A comparative study of satellite galaxies in Milky Way-like galaxies from HSC, DECaLS and SDSS
• Rapid Filamentary Accretion as the Origin of Extended Thin Discs
• The twisted dark matter halo of the Milky Way
• Is NGC 5824 the Core of the Progenitor of the Cetus Stream?
• How cosmological merger histories shape the diversity of stellar haloes
• The galaxy size to halo spin relation of disk galaxies in cosmological hydrodynamical simulations
• Substructure at High Speed II: The Local Escape Velocity and Milky Way Mass with Gaia DR2
• Evidence for a Massive Andromeda Galaxy Using Satellite Galaxy Proper Motions
• Milky Way-est: Cosmological Zoom-in Simulations with Large Magellanic Cloud and Gaia-Sausage-Enceladus Analogs
• Galaxy Flybys: Evolution of the Bulge, Disk, and Spiral Arms
• The oblateness of the Milky Way dark matter halo from the stellar streams of NGC 3201, M68, and Palomar 5
• Classifying globular clusters and applying them to estimate the mass of the Milky Way
• A portrait of the Vast Polar Structure as a young phenomenon: hints from its member satellites
• The Local Group's mass: probably no more than the sum of its parts
• The Age-Metallicity-Specific Orbital Energy Relation for the Milky Way's Globular Cluster System Confirms the Importance of Accretion for Its Formation
• Sizing from the Smallest Scales: The Mass of the Milky Way
• Can ultralight dark matter explain the age-velocity dispersion relation of the Milky Way disc: A revised and improved treatment
• The Milky Way, Coming into Focus: Precision Astrometry Probes its Evolution, and its Dark Matter
• The Escape Velocity Profile of the Milky Way from Gaia DR3
• Eta-Earth Revisited II: Deriving a Maximum Number of Earth-like Habitats in the Galactic Disk
• Weighing Milky Way and Andromeda in an expanding $\Lambda$CDM Universe: Decreasing the Local Group mass
• All-Sky Kinematics of the Distant Halo: The Reflex Response to the LMC
• On the Galactic rotation curve inferred from the Jeans equations Assessing its robustness using Gaia DR3 and cosmological simulations
• Galactic Mass Estimates using Dwarf Galaxies as Kinematic Tracers
• The outermost edges of the Milky Way halo from galaxy kinematics
• Constrained cosmological simulations of the Local Group using Bayesian hierarchical field-level inference
• The imprint of galaxy mergers on satellite planes in a cosmological context
• Constraining density and metallicity of the Milky Way's hot gas halo from O VII spectra and ram-pressure stripping
• Is the core-cusp problem a matter of perspective: Jeans Anisotropic Modeling against numerical simulations
• Apocalypse When? No Certainty of a Milky Way -- Andromeda Collision
• Proper motion measurements for stars up to $100$ kpc with Subaru HSC and SDSS Stripe 82
• The Local Group as a test system for Modified Newtonian Dynamics
• Chemodynamical study of two CEMP-no stars from the Hamburg/ESO Survey
• Non-Parametric Spherical Jeans Mass Estimation with B-splines
• Constraining the Milky Way Mass with Its Hot Gaseous Halo
• Determining Satellite Infall Times Using Machine Learning
• Equilibrium axisymmetric halo model for the Milky Way and its implications for direct and indirect DM searches
• RR Lyrae stars as probes of the outer Galactic halo: Chemical and kinematic analysis of a pilot sample
• ARTEMIS emulator: exploring the effect of cosmology and galaxy formation physics on Milky Way-mass haloes and their satellites
• Investigating the Dark Matter Halo of NGC 5128 using a Discrete Dynamical Model
• Modeling the Cosmic Dispersion Measure in the D < 120 Mpc Local Universe
• Comparison of the Orbital Properties of the Milky Way Globular Clusters from the Data of the Gaia DR2 and EDR3 Catalogs
• Gamma rays from dark matter spikes in EAGLE simulations
• Can tides explain the low dark matter density in Fornax?
• Galaxy groups in the presence of Cosmological Constant: Increasing the Masses of Groups
• The role of impact parameter in typical close galaxy flybys
• Sensitivity Estimation for Dark Matter Subhalos in Synthetic Gaia DR2 using Deep Learning
• Simulations of the accreted stellar halos of low-mass field galaxies
• The frozen outskirts: a cold Hubble flow and the mass of the Local Group
• Line-of-sight mass estimator and the masses of the Milky Way and Andromeda Galaxy
• Auriga Streams II: orbital properties of tidally disrupting satellites of Milky Way-mass galaxies
• How do the dynamics of the Milky Way -- Large Magellanic Cloud system affect gamma-ray constraints on particle dark matter?
• Uncover 3D Dark Matter Distribution of the Milky Way by an Empirical Triaxial Orbit-Superposition Model: Method Validation
• Line-of-Sight Velocity Projection Impact on the Local Group Mass
• Structure Formation Limits on Axion-Like Dark Matter
• Milky Way Mass Through Escape Velocity Curve from LAMOST K Giants
• Timing Mass of the Local Group
• The Milky Way and M31 Orbital History: Did the Local Group evolve in isolation?
• On the contribution of cosmic-ray interactions in the circumgalactic gas to the observed high-energy neutrino flux
• Quantifying the Milky Way, LMC and their interaction using all-sky kinematics of outer halo stars
• The mass and redshift dependence of halo star clustering
• Probabilistic Inference of the Structure and Orbit of Milky Way Satellites with Semi-Analytic Modeling
• Dynamical Models of the Milky Way in Action Space with LAMOST DR8 and GAIA EDR3
• Correlation between Outlying Halo Abundance and Host Halo Properties
• Determination of the best dark matter profile for the Milky Way with Gaia DR3 using Bayesian Model Comparison
• The long-term stability of the Vast Polar Structure and its connection to a possible previous passage of the LMC
• Broken Expectations: The Effects of Modelling Assumptions on the Inferred Dark Matter Distribution in the Milky Way's Satellites