Explanipedia

A Galactic Self-portrait: Density Structure and Integrated Properties of the Milky Way Disk Open

Julie Imig, Jon A. Holtzman, Gail Zasowski, Jianhui Lian, Nicholas Fraser Boardman , et al. · 2025

The evolutionary history of the Milky Way disk is imprinted in the ages, positions, and chemical compositions of individual stars. In this study, we derive the intrinsic density distribution of different stellar populations using the final…

SF-R You Sure? The Conflicting Role of Star Formation Rates in Constraining the Evolution of Milky Way Analogs in Cosmological Simulations Open

Alicia M. Savelli, Joshua S. Speagle, J. Ted Mackereth, Norman Murray, Kartheik G. Iyer · 2025

Milky Way analogs (MWAs) have long been studied by astronomers to place our Galaxy within an extragalactic context. With the power of cosmological simulations, we are now able to not only characterize MWAs today, but also watch as they evo…

SF-R You Sure? The Conflicting Role of Star Formation Rates in Constraining the Evolution of Milky Way Analogues in Cosmological Simulations Open

Alicia M. Savelli, Joshua S. Speagle, J. Ted Mackereth, Norman Murray, Kartheik G. Iyer · 2024

Milky Way analogues (MWAs) have long been studied by astronomers to place our Galaxy within an extragalactic context. With the power of cosmological simulations, we are now able to not only characterize MWAs today, but also watch as they e…

Disentangling Stellar Age Estimates from Galactic Chemodynamical Evolution Open

Jeff Shen, Joshua S. Speagle, J. Ted Mackereth, Yuan-Sen Ting, Jo Bovy · 2023

Stellar ages are key for determining the formation history of the Milky Way, but are difficult to measure precisely. Furthermore, methods that use chemical abundances to infer ages may entangle the intrinsic evolution of stars with the che…

The Galactic Interstellar Object Population: A Framework for Prediction and Inference Open

Matthew J. Hopkins, Chris Lintott, Michele T. Bannister, J. Ted Mackereth, John C. Forbes · 2023

The Milky Way is thought to host a huge population of interstellar objects (ISOs), numbering approximately 10 15 pc −3 around the Sun, which are formed and shaped by a diverse set of processes ranging from planet formation to Galactic dyna…

The stellar mass of the <i>Gaia</i>-Sausage/Enceladus accretion remnant Open

James Lane, Jo Bovy, J. Ted Mackereth · 2023

The Gaia-Sausage/Enceladus (GS/E) structure is an accretion remnant that comprises a large fraction of the Milky Way’s stellar halo. We study GS/E using high-purity samples of kinematically selected stars from APOGEE DR16 and Gaia. Employi…

MCMC chains representing stellar halo fits for Lane et al. (2023) paper published in MNRAS Open

James Lane, Jo Bovy, J. Ted Mackereth · 2023

Results for the paper entitled "The stellar mass of the Gaia-Sausage/Enceladus accretion remnant" published in MNRAS by Lane, Bovy, & Mackereth. The results are in the form of MCMC posterior chains, which are used to generate the results r…

MCMC chains representing stellar halo fits for Lane et al. (2023) paper published in MNRAS Open

James Lane, Jo Bovy, J. Ted Mackereth · 2023

Results for the paper entitled "The stellar mass of the Gaia-Sausage/Enceladus accretion remnant" published in MNRAS by Lane, Bovy, & Mackereth. The results are in the form of MCMC posterior chains, which are used to generate the results r…

The Galactic Interstellar Object Population: A Framework for Prediction and Inference Open

Matthew J. Hopkins, Chris Lintott, Michele T. Bannister, J. Ted Mackereth, John C. Forbes · 2023

The Milky Way is thought to host a huge population of interstellar objects (ISOs), numbering approximately $10^{15}\mathrm{pc}^{-3}$ around the Sun, which are formed and shaped by a diverse set of processes ranging from planet formation to…

The evolution of the Milky Way’s thin disc radial metallicity gradient with K2 asteroseismic ages Open

E. Willett, A. Miglio, J. Ted Mackereth, C. Chiappini, Alexander J Lyttle , et al. · 2023

The radial metallicity distribution of the Milky Way’s disc is an important observational constraint for models of the formation and evolution of our Galaxy. It informs our understanding of the chemical enrichment of the Galactic disc and …

The evolution of the Milky Way's thin disc radial metallicity gradient with K2 asteroseismic ages Open

E. Willett, A. Miglio, J. Ted Mackereth, C. Chiappini, Alexander J Lyttle , et al. · 2023

The radial metallicity distribution of the Milky Way's disc is an important observational constraint for models of the formation and evolution of our Galaxy. It informs our understanding of the chemical enrichment of the Galactic disc and …

The stellar mass of the Gaia-Sausage/Enceladus accretion remnant Open

J. Matthew D. Lane, Jo Bovy, J. Ted Mackereth · 2023

The \textit{Gaia}-Sausage/Enceladus (GS/E) structure is an accretion remnant which comprises a large fraction of the Milky Way's stellar halo. We study GS/E using high-purity samples of kinematically selected stars from APOGEE DR16 and \te…

Disentangling Stellar Age Estimates from Galactic Chemodynamical Evolution Open

Jeff Shen, Joshua S. Speagle, J. Ted Mackereth, Yuan-Sen Ting, Jo Bovy · 2023

Stellar ages are key for determining the formation history of the Milky Way, but are difficult to measure precisely. Furthermore, methods that use chemical abundances to infer ages may entangle the intrinsic evolution of stars with the che…

A variational encoder–decoder approach to precise spectroscopic age estimation for large Galactic surveys Open

Henry Leung, Jo Bovy, J. Ted Mackereth, A. Miglio · 2023

Constraints on the formation and evolution of the Milky Way Galaxy require multidimensional measurements of kinematics, abundances, and ages for a large population of stars. Ages for luminous giants, which can be seen to large distances, a…

A variational encoder-decoder approach to precise spectroscopic age estimation for large Galactic surveys Open

Henry Leung, Jo Bovy, J. Ted Mackereth, A. Miglio · 2023

Constraints on the formation and evolution of the Milky Way Galaxy require multi-dimensional measurements of kinematics, abundances, and ages for a large population of stars. Ages for luminous giants, which can be seen to large distances, …

A measurement of the distance to the Galactic centre using the kinematics of bar stars Open

Henry Leung, Jo Bovy, J. Ted Mackereth, John Douglas Hunt, Richard R. Lane , et al. · 2022

The distance to the Galactic centre R0 is a fundamental parameter for understanding the Milky Way, because all observations of our Galaxy are made from our heliocentric reference point. The uncertainty in R0 limits our knowledge of many as…

Correction to: The contribution of N-rich stars to the Galactic stellar halo using APOGEE red giants Open

Danny Horta, J. Ted Mackereth, Ricardo P. Schiavon, Sten Hasselquist, Jo Bovy , et al. · 2022

This is a correction to the paper 'The contribution of N-rich stars to the Galactic stellar halo using APOGEE red giants' (

The chemical characterization of halo substructure in the Milky Way based on APOGEE Open

Danny Horta, Ricardo P. Schiavon, J. Ted Mackereth, David H. Weinberg, Sten Hasselquist , et al. · 2022

Galactic haloes in a Λ-CDM universe are predicted to host today a swarm of debris resulting from cannibalized dwarf galaxies. The chemodynamical information recorded in their stellar populations helps elucidate their nature, constraining t…

Simulated Bars May Be Shorter but Are Not Slower Than Those Observed: TNG50 versus MaNGA Open

Neige Frankel, Annalisa Pillepich, Hans‐Walter Rix, Vicente Rodríguez-Gómez, Jason L. Sanders , et al. · 2022

Galactic bars are prominent dynamical structures within disk galaxies whose size, formation time, strength, and pattern speed influence the dynamical evolution of their hosts’ galaxies. Yet, their formation and evolution in a cosmological …

Chemical Cartography with APOGEE: Mapping Disk Populations with a 2-process Model and Residual Abundances Open

David H. Weinberg, Jon A. Holtzman, Jennifer A. Johnson, Christian R. Hayes, Sten Hasselquist , et al. · 2022

We apply a novel statistical analysis to measurements of 16 elemental abundances in 34,410 Milky Way disk stars from the final data release (DR17) of APOGEE-2. Building on recent work, we fit median abundance ratio trends [X/Mg] versus [Mg…

A direct measurement of the distance to the Galactic center using the kinematics of bar stars Open

Henry Leung, Jo Bovy, J. Ted Mackereth, John Douglas Hunt, Richard R. Lane , et al. · 2022

The distance to the Galactic center $R_0$ is a fundamental parameter for understanding the Milky Way, because all observations of our Galaxy are made from our heliocentric reference point. The uncertainty in $R_0$ limits our knowledge of m…

The Milky Way tomography with APOGEE: intrinsic density distribution and structure of mono-abundance populations Open

Jianhui Lian, Gail Zasowski, J. Ted Mackereth, Julie Imig, Jon A. Holtzman , et al. · 2022

The spatial distribution of mono-abundance populations (MAPs, selected in [Fe/H] and [Mg/Fe]) reflect the chemical and structural evolution in a galaxy and impose strong constraints on galaxy formation models. In this paper, we use APOGEE …

The chemical characterisation of halo substructure in the Milky Way based on APOGEE Open

Danny Horta, Ricardo P. Schiavon, J. Ted Mackereth, David H. Weinberg, Sten Hasselquist , et al. · 2022

Galactic haloes in a $Λ$-CDM universe are predicted to host today a swarm of debris resulting from cannibalised dwarf galaxies. The chemo-dynamical information recorded in their stellar populations helps elucidate their nature, constrainin…

Simulated Bars May Be Shorter But Are Not Slower Than Observed: TNG50 vs. MaNGA Open

Neige Frankel, Annalisa Pillepich, Hans‐Walter Rix, Vicente Rodríguez-Gómez, Jason L. Sanders , et al. · 2022

Galactic bars are prominent dynamical structures within disk galaxies whose size, formation time, strength, and pattern speed influence the dynamical evolution of their hosts galaxies. Yet, their formation and evolution in a cosmological c…

The kinematic properties of Milky Way stellar halo populations Open

James Lane, Jo Bovy, J. Ted Mackereth · 2021

In the Gaia era, stellar kinematics are extensively used to study Galactic halo stellar populations, to search for halo structures, and to characterize the interface between the halo and hot disc populations. We use distribution function-b…

Predicting the Water Content of Interstellar Objects from Galactic Star Formation Histories Open

Chris Lintott, Michele T. Bannister, J. Ted Mackereth · 2021

Planetesimals inevitably bear the signatures of their natal environment, preserving in their composition a record of the metallicity of their system’s original gas and dust, albeit one altered by the formation processes. When planetesimals…

APOGEE detection of N-rich stars in the tidal tails of Palomar 5 Open

Siân Phillips, Ricardo P. Schiavon, J. Ted Mackereth, Carlos Allende Prieto, Borja Anguiano , et al. · 2021

Recent results from chemical tagging studies using Apache Point Observatory Galactic Evolution Experiment data suggest a strong link between the chemical abundance patterns of stars found within globular clusters (GC), and chemically pecul…

New Families in our Solar Neighborhood: Applying Gaussian Mixture Models for Objective Classification of Structures in the Milky Way and in Simulations Open

Farnik Nikakhtar, Robyn E. Sanderson, Andrew Wetzel, Sarah Loebman, Sanjib Sharma , et al. · 2021

The standard picture of galaxy formation motivates the decomposition of the Milky Way into 3–4 stellar populations with distinct kinematic and elemental abundance distributions: the thin disk, thick disk, bulge, and stellar halo. To test t…

Chemical Cartography with APOGEE: Mapping Disk Populations with a Two-Process Model and Residual Abundances Open

David H. Weinberg, Jon A. Holtzman, Jennifer A. Johnson, Christian R. Hayes, Sten Hasselquist , et al. · 2021

We apply a novel statistical analysis to measurements of 16 elemental abundances in 34,410 Milky Way disk stars from the final data release (DR17) of APOGEE-2. Building on recent work, we fit median abundance ratio trends [X/Mg] vs. [Mg/H]…

New families in our Solar neighborhood: applying Gaussian Mixture models\n for objective classification of structures in the Milky Way and in\n simulations Open

Farnik Nikakhtar, Robyn E. Sanderson, Andrew Wetzel, Sarah Loebman, Sanjib Sharma , et al. · 2021

The standard picture of galaxy formation motivates the decomposition of the\nMilky Way into 3--4 stellar populations with distinct kinematic and elemental\nabundance distributions: the thin disk, thick disk, bulge, and stellar halo. To\nte…

J. Ted Mackereth YOU? Author Swipe