Sagittarius: The Nearest Dwarf Galaxy

Abstract

We have discovered a new Galactic satellite galaxy in the constellation of Sagittarius. The Sagittarius dwarf galaxy is the nearest galaxy known, subtends an angle of $>10$ degrees on the sky, lies at a distance of $24 \kpc$ from the Sun, $\sim 16 \kpc$ from the centre of the Milky Way. Itis comparable in size and luminosity to the largest dwarf spheroidal, has a well populated red horizontal branch with a blue HB extension; a substantial carbon star population; and a strong intermediate age stellar component with evidence of a metallicity spread. Isodensity maps show it to be markedly elongated along a direction pointing towards the Galactic centre and suggest that it has been tidally distorted. The close proximity to the Galactic centre, the morphological appearance and the radial velocity of 140 km/s indicate that this system must have undergone at most very few close orbital encounters with the Milky Way. It is currently undergoing strong tidal disruption prior to being integrated into the Galaxy. Probably all of the four globular clusters, M54, Arp 2, Ter 7 and Ter 8, are associated with the Sagittarius dwarf galaxy, and will probably share the fate of their progenitor.

MNRAS in press, 22pp uuencoded PS file, 26 printed figures available on request from [email protected]

Cited by in corpus (235)

• The New Galaxy: Signatures of its Formation
• A 2MASS All-Sky View of the Sagittarius Dwarf Galaxy: I. Morphology of the Sagittarius Core and Tidal Arms
• Tracing Galaxy Formation with Stellar Halos I: Methods
• VISTA Variables in the Via Lactea (VVV): The public ESO near-IR variability survey of the Milky Way
• The Field of Streams: Sagittarius and its Siblings
• Rotation Curves of Spiral Galaxies
• Cats and Dogs, Hair and A Hero: A Quintet of New Milky Way Companions
• Stellar Chemical Signatures And Hierarchical Galaxy Formation
• The Ghost of Sagittarius and Lumps in the Halo of the Milky Way
• A Universal Mass Profile for Dwarf Spheroidal Galaxies?
• Near-Field Cosmology with Metal-Poor Stars
• The ACS Survey of Galactic Globular Clusters. VII. Relative Ages
• The Ages of 55 Globular Clusters as Determined Using an Improved delta V_TO^HB Method Along with Color-Magnitude Diagram Constraints, and Their Implications for Broader Issues
• The accretion origin of the Milky Way's stellar halo
• The ACS Virgo Cluster Survey IX: The Color Distributions of Globular Cluster Systems in Early-Type Galaxies
• Evidence for Stellar Substructure in the Halo and Outer Disk of M31
• The Formation of Giant Elliptical Galaxies and Their Globular Cluster Systems
• The properties and luminosity function of extremely low luminosity galaxies
• A New Milky Way Dwarf Satellite in Canes Venatici
• Identification of A-colored Stars and Structure in the Halo of the Milky Way from SDSS Commissioning Data
• A Revised Parallel-Sequence Morphological Classification of Galaxies: Structure and Formation of S0 and Spheroidal Galaxies
• A 2MASS All-Sky View of the Sagittarius Dwarf Galaxy: IV. Modeling the Sagittarius Tidal Tails
• Horizontal Branch Stars: The Interplay between Observations and Theory, and Insights into the Formation of the Galaxy
• Galaxia: a code to generate a synthetic survey of the Milky Way
• The SDSS-III Baryon Oscillation Spectroscopic Survey: Quasar Target Selection for Data Release Nine
• The Milky Way stellar halo out to 40 kpc : Squashed, broken but smooth
• The properties of Galactic globular cluster sub-systems
• The Split Red Clump of the Galactic Bulge from OGLE-III
• Full One-loop Calculation of Neutralino Annihilation into Two Photons
• The exotic chemical composition of the Sagittarius dwarf Spheroidal galaxy
• Dark matter heats up in dwarf galaxies
• Internal Kinematics of the Fornax Dwarf Spheroidal Galaxy
• Elemental Abundance Ratios in Stars of the Outer Galactic Disk. I. Open Clusters
• Chemical Abundance Distributions of Galactic Halos and their Satellite Systems in a Lambda CDM Universe
• Testing LMC Microlensing Scenarios: The Discrimination Power of the SuperMACHO Microlensing Survey
• Comparing the properties of local globular cluster systems: implications for the formation of the Galactic halo
• Dynamical Blueprints for Galaxies
• Galactic accretion and the outer structure of galaxies in the CDM model
• Accurate Stellar Kinematics at Faint Magnitudes: application to the Bootes~I dwarf spheroidal galaxy
• Broken and unbroken: the Milky Way and M31 stellar haloes
• The Ubiquity of the Rapid Neutron-Capture Process
• Kinematics of the stellar halo and the mass distribution of the Milky Way using BHB stars
• Contributions to the accreted stellar halo: an atlas of stellar deposition
• Pre-galactic metal enrichment - The chemical signatures of the first stars
• Quantifying Kinematic Substructure in the Milky Way's Stellar Halo
• Kinematics of SDSS subdwarfs: Structure and substructure of the Milky Way halo
• A Two Micron All-Sky Survey View of the Sagittarius Dwarf Galaxy: II. Swope Telescope Spectroscopy of M Giant Stars in the Dynamically Cold Sagittarius Tidal Stream
• The Ital-FLAMES survey of the Sagittarius dwarf Spheroidal galaxy. I. Chemical abundances of bright RGB stars
• Ages and kinematics of chemically selected, accreted Milky Way halo stars
• Exploring Halo Substructure with Giant Stars: I. Survey Description and Calibration of the Photometric Search Technique
• The Next Generation Virgo Cluster Survey. XXIII. Fundamentals of nuclear star clusters over seven decades in galaxy mass
• Dynamical Relics of the Ancient Galactic Halo
• Taking the Measure of the Universe: Precision Astrometry with SIM PlanetQuest
• Tidal Tails Test the Equivalence Principle in the Dark Sector
• Is the Milky Way ringing? The hunt for high velocity streams
• Exploring Halo Substructure with Giant Stars X. Extended Dark Matter or Tidal Disruption?: The Case for the Leo I Dwarf Spheroidal Galaxy
• Abundances for metal-poor stars with accurate parallaxes II. alpha-elements in the halo
• Galaxy Populations and Evolution in Clusters III. The Origin of Low-Mass Galaxies in Clusters: Constraints from Stellar Populations
• Re-Assembling the Sagittarius Dwarf Galaxy
• Detectability of Weakly Interacting Massive Particles in the Sagittarius Dwarf Tidal Stream
• The Bizarre Chemical Inventory of NGC 2419, An Extreme Outer Halo Globular Cluster
• Was the Progenitor of the Sagittarius Stream a Disc Galaxy?
• Chemical Compositions of Red Giant Stars in Old Large Magellanic Cloud Globular Clusters
• Exploring Halo Substructure with Giant Stars IV: The Extended Structure of the Ursa Minor Dwarf Spheroidal
• Simple dynamical models of the Sagittarius dwarf galaxy
• Evidence for the Hierarchical Formation of the Galactic Spheroid
• The Sgr dSph hosts a metal-rich population
• The last breath of the Sagittarius dSph
• Stream-orbit misalignment I: The dangers of orbit-fitting
• Galactic Indigestion: Numerical Simulations of the Milky Way's Closest Neighbor
• The outer halo globular cluster system of M31 - II. Kinematics
• Constraining the History of the Sagittarius Dwarf Galaxy Using Observations of its Tidal Debris
• Are Ti44-Producing Supernovae Exceptional?
• Observations of the Sagittarius Dwarf galaxy by the H.E.S.S. experiment and search for a Dark Matter signal
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• On the alleged duality of the Galactic halo
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• Touching The Void: A Striking Drop in Stellar Halo Density Beyond 50 kpc
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• Reconstructing the Disrupted Dwarf Galaxy $Gaia$-Sausage/Enceladus Using its Stars and Globular Clusters
• Sloan Digital Sky Survey Imaging of Low Galactic Latitude Fields: Technical Summary and Data Release
• The Accreted Nuclear Clusters of the Milky Way
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• Low-resolution spectroscopy of main sequence stars belonging to 12 Galactic globular clusters. I. CH and CN band strength variations
• The metallicity extremes of the Sagittarius dSph using SALT spectroscopy of PNe
• NGC 2419 -- Another Remnant of Accretion by the Milky Way
• Exploring Halo Substructure with Giant Stars VIII: The Extended Structure of the Sculptor Dwarf Spheroidal Galaxy
• r-process Production Sites as inferred from Eu Abundances in Dwarf Galaxies
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• The Local Group as a time machine: studying the high-redshift Universe with nearby galaxies
• Terzan 8: a Sagittarius-flavoured globular cluster
• Metallicity and $\alpha$-element Abundance Gradients along the Sagittarius Stream as Seen by APOGEE
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• Characterising stellar halo populations I: An extended distribution function for halo K giants
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• The Outer Envelopes of Globular Clusters. I. NGC 7089 (M2)
• The Alpha-element knee of the Sagittarius Stream
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• The Structure of the Sagittarius Stellar Stream as Traced by Blue Horizontal Branch Stars
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• Detailed Chemical Abundances in NGC 5824: Another Metal-Poor Globular Cluster with Internal Heavy Element Abundance Variations
• Pulsating Variable Stars in the Coma Berenices dwarf spheroidal galaxy
• The outer halo globular cluster system of M31 - III. Relationship to the stellar halo
• Testing galaxy formation models with the GHOSTS survey: The color profile of M81's stellar halo
• An Extragalactic HI Cloud with No Optical Counterpart?
• A New Analysis of RR Lyrae Kinematics in the Solar Neighborhood
• Fossil stellar streams and their globular cluster populations in the E-MOSAICS simulations
• A wide-field photometric survey for extratidal tails around five metal-poor globular clusters in the Galactic halo
• Blue Horizontal Branch Stars in the Sagittarius dwarf spheroidal galaxy
• The ACS Survey of Galactic Globular Clusters XI: The Three-Dimensional Orientation of the Sagittarius Dwarf Spheroidal Galaxy and its Globular Clusters
• Young accreted globular clusters in the outer halo of M31
• The Sagittarius Dwarf Galaxy Survey (SDGS) I: CMDs, Reddening and Population Gradients. First evidences of a very metal poor population
• A 2MASS All-Sky View of the Sagittarius Dwarf Galaxy: VII. Kinematics of the Main Body of the Sagittarius dSph
• On the Predicted and Observed Color Boundaries of the RR Lyrae Instability Strip as a Function of Metallicity
• Identifying Sagittarius Stream Stars By Their APOGEE Chemical Abundance Signatures
• Gravitational Microlensing and the Galactic Halo
• Is the LMC Microlensing Due to an Intervening Dwarf Galaxy?
• A Tale Twice Told: The Luminosity Profiles of the Sagittarius Tails
• Metallicity Bias in the Kinematics of the Milky Way Stellar Halo
• Tracing Kinematic and Chemical Properties of Sagittarius Stream by K-Giants, M-Giants, and BHB stars
• The Northern wraps of the Sagittarius Stream as traced by Red Clump stars: distances, intrinsic widths and stellar densities
• The Sagittarius stream in Gaia eDR3 and the origin of the bifurcations
• Testing cold dark matter with the low mass Tully-Fisher relation
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• The M33 Globular Cluster System with PAndAS Data: The Last Outer Halo Cluster?
• Multiplicity and period distribution of Population II field stars in solar vicinity
• Revealing the Complicated Story of the Cetus Stream with StarGO
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• Chemical Abundances of Planetary Nebulae in the Sagittarius Dwarf Elliptical Galaxy
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• The 2MASS Color-Magnitude Diagram of the Center of the Sagittarius Dwarf Galaxy: Photometric Measurements of a Surprisingly High Mean Metallicity
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• Newly Discovered RR Lyrae Stars in the SDSSXPanXSTARRS1XCatalina Footprint
• The Cosmological Significance of High-Velocity Cloud Complex H
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• Group Finding in the Stellar Halo using Photometric Surveys: Current Sensitivity and Future Prospects
• Carbon enrichment of the evolved stars in the Sagittarius dwarf spheroidal
• Modelling the chemical evolution of the Galaxy halo
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• Phase-space Properties and Chemistry of the Sagittarius Stellar Stream Down to the Extremely Metal-poor ($[Fe/H]\lesssim -3$) Regime
• Major Substructure in the M31 Outer Halo: the South-West Cloud
• Are Some Milky Way Globular Clusters Hosted by Undiscovered Galaxies?
• Light Dark Matter Annihilations into Two Photons
• A wide angle view of the Sagittarius dwarf Spheroidal Galaxy. I: VIMOS photometry and radial velocities across Sgr dSph major and minor axis
• Constraining the Milky Way assembly history with Galactic Archaeology. Ludwig Biermann Award Lecture 2015
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• The Kapteyn moving group is not tidal debris from $\omega$ Centauri
• The Panchromatic Hubble Andromeda Treasury II. Tracing the Inner M31 Halo with Blue Horizontal Branch Stars
• VISTA variables in the Sagittarius dwarf spheroidal galaxy: pulsation- vs. dust-driven winds on the giant branches
• Absolute Proper Motions to B~22.5: V. Detection of Sagittarius Dwarf Spheroidal Debris in the Direction of the Galactic Anticenter
• Color-Magnitude Diagrams of Merged Globular Clusters: Metallicity Effects
• The Effect of Substructure on Mass Estimates of Galaxies
• Probing the Halo From the Solar Vicinity to the Outer Galaxy: Connecting Stars in Local Velocity Structures to Large-Scale Clouds
• VISTA's view of the Sagittarius dwarf spheroidal galaxy and southern Galactic Bulge
• 60 candidate high-velocity stars originating from the Sagittarius dwarf spheroidal galaxy in Gaia EDR3
• Dynamical flows through Dark Matter Haloes II: one and two points statistics at the virial radius
• Peeking beneath the precision floor I: metallicity spreads and multiple elemental dispersions in the globular clusters NGC 288 and NGC 362
• Searching for Machos (and other Dark Matter Candidates) in a Simulated Galaxy
• Discovery of 18 stars with -3.10 < [Fe/H] < -1.45 in the Sagittarius dwarf galaxy
• Eight more low luminosity globular clusters in the Sagittarius dwarf galaxy
• The Next Generation Virgo Cluster Survey. XIX. Tomography of Milky Way Substructures in the NGVS Footprint
• On the Edge: the relation between stellar and dark matter haloes of Milky Way-mass galaxies
• The Sagittarius dwarf galaxy as a microlensing target
• Extra-tidal star candidates in globular clusters of the Sagittarius dwarf spheroidal galaxy
• A search for stellar X-ray sourcesin the Sagittarius and Carina dwarf galaxies - I: X-ray observations
• Ironing the folds: The phase space chevrons of a GSE-like merger as a dark matter subhalo detector
• Fabry-Perot Absorption Line Spectroscopy of the Galactic Bar. II. Stellar Metallicities
• The Celestial Buffet: multiple populations and globular cluster formation in dwarf galaxies
• The Dark Matter Tidal Stripping History of the Sagittarius Core with N-body simulations
• Chandra observations of the globular cluster M54
• The Massive M31 Cluster G1: Detailed Chemical Abundances from Integrated Light Spectroscopy
• Tidal stripping stellar substructures around four metal-poor globular clusters in the Galactic bulge
• Hidden deep in the halo: selection of a reduced proper motion halo catalogue and mining retrograde streams in the velocity space
• Chemical Abundances in the PN Wray16-423 in the Sagittarius Dwarf Spheroidal Galaxy: Constraining the Dust Composition
• An optimized Method to Identify RR Lyrae stars in the SDSS X Pan-STARRS1 Overlapping Area Using a Bayesian Generative Technique
• Two Portions of Sagittarius Stream in the LAMOST Complete Spectroscopic Survey of Pointing Area at Southern Galactic Cap
• Observations and Theory of Star Cluster Formation
• Leaves on trees: identifying halo stars with extreme gradient boosted trees
• Spectroscopy of Giants of the Sagittarius Dwarf Galaxy
• Flares, Warps, Truncations, and Satellite: The Ultra-thin Galaxy UGC 11859
• Population gradients and photometric metallicities in early- and transition-type dwarf galaxies: Clues from the Sculptor group
• The kinematics of globular clusters systems in the outer halos of the Aquarius simulations
• AuriDESI: Mock Catalogues for the DESI Milky Way Survey
• Stars, Star Clusters, and Dust in NGC 3077
• The Chemodynamical Nature of the Triangulum-Andromeda Overdensity
• Fitting the density substructure of the stellar halo with MilkyWay@home
• UGC 7388: a galaxy with two tidal loops
• Luminous Satellites versus Dark Subhaloes: Clustering in the Milky Way
• Nuclear star clusters as probes of dark matter halos: the case of the Sagittarius Dwarf Spheroidal Galaxy
• Architecture of the Andromeda: a quantitative analysis of clustering in the inner stellar halo
• V5852 Sgr: An Unusual Nova Possibly Associated with the Sagittarius Stream
• The Resolved Red Giant Branches of E/S0 Galaxies
• Variable Stars in Sagittarius Globular Clusters I. Arp~2
• Discovery of Galactic center ejected star in DESI DR1
• Tidally-induced radial migration waves in LMC-like galaxies
• Predicting Images for the Dynamics Of stellar Clusters (π-DOC): a deep learning framework to predict mass, distance and age of globular clusters
• Rethinking Habitability using Biogenic Precursors: Formaldehyde in Millimeter Molecular Clouds of the Inner Galaxy
• Chemical analysis of carbon stars in the Local Group: I. The Small Magellanic Cloud and the Sagittarius dwarf spheroidal galaxy
• A Search for Wandering Black Holes in the Milky Way with Gaia and DECaLS
• Milky Way globular cluster dynamics: are they preferentially co-rotating?
• Statistical analysis of Galactic globular cluster type properties
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• Current Status of the Microlensing Surveys
• The Escape of Globular Clusters from the Satellite Dwarf Galaxies of the Milky Way
• Abundances in Sagittarius: present state and perspectives for the use of VLT
• Chemical Composition of a Palomar 12 Blue Straggler
• COSTA: the COld STream finder Algorithm. Searching for kinematical substructures in the phase space of discrete tracers
• The Future of Stellar Populations Studies in the Milky Way and the Local Group
• Is the Sgr dSph a dark matter dominated system?