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Related papers: Revisiting the Tale of Hercules: how stars orbitin…

200 papers

Based on published sources, we have created a kinematic database on 220 massive (>10 solar masses) young Galactic star systems located within <3 kpc of the Sun. Out of them, approximately 100 objects are spectroscopic binary and multiple…

Astrophysics of Galaxies · Physics 2013-07-08 V. V. Bobylev , A. T. Bajkova

We describe the structure and composition of six major stellar streams in a population of 20 574 local stars in the New Hipparcos Reduction with known radial velocities. We find that, once fast moving stars are excluded, almost all stars…

General Physics · Physics 2010-01-15 Charles Francis , Erik Anderson

Hercules is a dwarf spheroidal satellite of the Milky Way, found at a distance of about 138 kpc, and showing evidence of tidal disruption. It is very elongated and exhibits a velocity gradient of 16 +/- 3 km/s/kpc. Using this data a…

Astrophysics of Galaxies · Physics 2015-06-22 M. Blana , M. Fellhauer , R. Smith , G. N. Candlish , R. Cohen , J. P. Farias

This work explores dynamical models of the Milky Way (MW) by analyzing a sample of 86,109 K giant stars selected through cross-matching the LAMOST DR8 and Gaia EDR3 surveys. Our earlier torus models in Wang et al. (2017) did not include…

Astrophysics of Galaxies · Physics 2025-05-26 Guang-Chen Sun , Qiao Wang , Shude Mao , Yichao Li , Richard J. Long , Ping-Jie Ding , Yougang Wang , Xin Zhang , Xuelei Chen

We present evidence for a new Milky Way stellar tidal stream in the direction of the Andromeda and Triangulum (M31 and M33) galaxies. Using a matched-filter technique, we search the Sloan Digital Sky Survey Data Release 8 by creating…

Astrophysics of Galaxies · Physics 2015-06-11 Ana Bonaca , Marla Geha , Nitya Kallivayalil

We present a search for new members of the 300 km s$^{-1}$ stream (300S) near the dwarf galaxy Segue 1 using wide-field survey data. We identify 11 previously unknown bright stream members in the APOGEE-2 and SEGUE-1 and 2 spectroscopic…

This paper presents the detailed results obtained in the search of density- velocity inhomogeneities in a volume limited and absolute magnitude limited sample of A-F type dwarfs within 125 parsecs of the Sun. A 3-D wavelet analysis is used…

Astrophysics · Physics 2009-10-30 E. Chereul , M. Crézé , O. Bienaymé

We report the discovery of a large, dynamically cold, coeval stellar stream that is currently traversing the immediate solar neighborhood at a distance of only 100 pc. The structure was identified in a wavelet decomposition of the 3D…

Astrophysics of Galaxies · Physics 2019-02-20 Stefan Meingast , João Alves , Verena Fürnkranz

The Sun is a magnetic star, and the only spatio-temporally resolved astrophysical system displaying turbulent MHD thermal convection. This makes it a privileged object of study to understand fluid turbulence in extreme regimes and its…

Solar and Stellar Astrophysics · Physics 2025-04-16 F. Rincon , P. Barrère , T. Roudier

We investigate the possibility that the dwarf galaxies Crater II and Hercules have previously been tidally stripped by the Milky Way. We present Magellan/IMACS spectra of candidate member stars in both objects. We identify 37 members of…

Astrophysics of Galaxies · Physics 2019-09-25 Sal Wanying Fu , Joshua D. Simon , Alex G. Alarcón Jara

We reveal the highly structured nature of the Milky Way stellar halo within the footprint of the PAndAS photometric survey from blue main sequence and main sequence turn-off stars. We map no fewer than five stellar structures within a…

We develop statistical methods for identifying star streams in the halo of the Milky Way galaxy that exploit observed spatial and radial velocity distributions. Within a great circle, departures of the observed spatial distribution from…

Astrophysics of Galaxies · Physics 2015-06-03 Charles King , Warren R. Brown , Margaret J. Geller , Scott J. Kenyon

Hercules is the prototype of the ultra-faint dwarf (UFD) galaxies. To date, there are still no firm constraints on its total luminosity, due to the difficulty of disentangling Hercules bona-fide stars from the severe Galactic field…

Stellar streams are sensitive tracers of the gravitational potential, which is typically assumed to be static in the inner Galaxy. However, massive mergers like Gaia-Sausage-Enceladus can impart torques on the stellar disk of the Milky Way…

Astrophysics of Galaxies · Physics 2023-12-18 Jacob Nibauer , Ana Bonaca , Mariangela Lisanti , Denis Erkal , Zoe Hastings

It has been recently shown that the halo near the Sun contains several kinematic substructures associated to past accretion events. For the more distant halo, there is evidence of large-scale density variations -- in the form of stellar…

Astrophysics of Galaxies · Physics 2021-10-04 E. Balbinot , A. Helmi

We present a model for the interaction of the GD-1 stellar stream with a massive perturber that naturally explains many of the observed stream features, including a gap and an off-stream spur of stars. The model involves an impulse by a…

Astrophysics of Galaxies · Physics 2019-07-31 Ana Bonaca , David W. Hogg , Adrian M. Price-Whelan , Charlie Conroy

We use a novel cluster identification tool StarGO to explore the metal poor ([Fe/H] $<$ -1.5) outer stellar halo (d $>$ 15 kpc) of the Milky Way using data from Gaia, LAMOST and SDSS. Our method is built using an unsupervised learning…

Astrophysics of Galaxies · Physics 2019-09-04 Zhen Yuan , M. C. Smith , Xiang-Xiang Xue , Jing Li , Chao Liu , Yue Wang , Lu Li , Jiang Chang

We studied 12 disk streams found in a 250$^3$ pc$^3$ volume in the solar neighborhood, which we define as coeval and comoving stellar structures with aspect ratios greater than 3:1. Using Gaia Data Release 3 data and the advanced clustering…

Astrophysics of Galaxies · Physics 2025-09-11 Sebastian Ratzenböck , João Alves , Emily L. Hunt , Núria Miret-Roig , Stefan Meingast , Torsten Möller

The observed gas dynamics in the Milky Way can only be explained by a bar in the galactic center. Such a bar is directly visible in the near-IR maps of the bulge, where it causes a distinctive asymmetric light distribution pattern. Another…

Astrophysics · Physics 2007-05-23 Peter Englmaier

The nature of our Milky Way Galaxy is reexamined from an eclectic point of view. Evidence for a central bar, for example, is not reflected in the distribution of RR Lyrae variables in the central bulge [4,5], and it is not clear if either a…

Astrophysics of Galaxies · Physics 2015-06-17 David G. Turner