Results 71 to 80 of about 10,594 (212)

The Hubble Space Telescope Survey of M31 Satellite Galaxies. II. The Star Formation Histories of Ultrafaint Dwarf Galaxies

The Astrophysical Journal, 2023
We present the lifetime star formation histories (SFHs) for six ultrafaint dwarf (UFD; M _V > − 7.0, $4.9\lt {\mathrm{log}}_{10}({M}_{* }(z=0)/{M}_{\odot })\lt 5.5$ ) satellite galaxies of M31 based on deep color–magnitude diagrams constructed from ...
Alessandro Savino, Daniel R. Weisz, Evan D. Skillman, Andrew Dolphin, Andrew A. Cole, Nitya Kallivayalil, Andrew Wetzel, Jay Anderson, Gurtina Besla, Michael Boylan-Kolchin, Thomas M. Brown, James S. Bullock, Michelle L. M. Collins, M. C. Cooper, Alis J. Deason, Aaron L. Dotter, Mark Fardal, Annette M. N. Ferguson, Tobias K. Fritz, Marla C. Geha, Karoline M. Gilbert, Puragra Guhathakurta, Rodrigo Ibata, Michael J. Irwin, Myoungwon Jeon, Evan N. Kirby, Geraint F. Lewis, Dougal Mackey, Steven R. Majewski, Nicolas Martin, Alan McConnachie, Ekta Patel, R. Michael Rich, Joshua D. Simon, Sangmo Tony Sohn, Erik J. Tollerud, Roeland P. van der Marel   +36 more
doaj   +1 more source

PAndAS' cubs: discovery of two new dwarf galaxies in the surroundings of the Andromeda and Triangulum galaxies

, 2009
We present the discovery of two new dwarf galaxies, Andromeda XXI and Andromeda XXII, located in the surroundings of the Andromeda and Triangulum galaxies (M31 and M33).
Alan W. McConnachie, Annette M. N. Ferguson, Arif Babul, Armandroff, Bellazzini, Chapman, Davenhall, Dotter, Ferguson, Ferguson, Geraint F. Lewis, Grcevich, Huxor, Ibata, Irwin, John Dubinski, Julio Navarro, Karachentsev, Komatsu, Koposov, Lawrence M. Widrow, Majewski, Mark Fardal, Martin, McConnachie, McConnachie, Mike Irwin, Morrison, Navarro, Nicolas F. Martin, Peñarrubia, R. Michael Rich, Rodrigo A. Ibata, Schlegel, Scott Chapman, Tikhonov, Tolstoy, Walsh, Zucker, Zucker   +39 more
core   +1 more source

Morphological transformation of dwarf galaxies in the Local Group [PDF]

, 2015
In the Local Group there are three main types of dwarf galaxies: Dwarf Irregulars, Dwarf Spheroidals, and Dwarf Ellipticals. Intermediate/transitional types are present as well.
Carraro, Giovanni
core   +1 more source

Reflecting on Our Present Self‐Awareness of Not Having Found Any Life Beyond Earth

Earth and Space Science, Volume 11, Issue 1, January 2024.
Abstract Ever gazed at the stars and wondered if we’re alone? Scientists have been on a quest to find life beyond Earth, but no aliens yet. It’s tough because space is huge, and potential life is incredibly far away, making it difficult to detect their signals. Despite this, our ability to search is improving.
Stuart F. Taylor, Jonathan H. Jiang, Nick Searra, Philip E. Rosen   +3 more
wiley   +1 more source

A Comparison Between the Half-Light Radii, Luminosities, and UBV Colors of Globular Clusters in M31 and the Galaxy

, 2010
The Milky Way System and the Andromeda galaxy experienced radically different evolutionary histories. Nevertheless, it is found that these two galaxies ended up with globular cluster systems in which individual clusters have indistinguishable ...
Barmby, Brown, Giuricin, Hammer, Jester, Jordán, Law, Masters, Murphy, Nair, Peacock, Peacock, Perrett, Shapley, Sidney van den Bergh, van den Bergh, Wang   +16 more
core   +1 more source

The Local Group as a test of cosmological models [PDF]

, 1996
The dynamics of the Local Group and its environment provide a unique challenge to cosmological models. The velocity field within 5h-1 Mpc of the Local Group (LG) is extremely ``cold''.
Aaronson, Bahcall, Bardeen, Binney, Bohringer, Bond, Branchini, Brandenberger, Bunn, Bushouse, Cen, Cen, Cen, Cen, Cen, Dikaiakos, Dressler, Dunn, Eke, Faber, Fisher, Frederic, Freedman, Gardner, Gelato, Gelb, Gelb, Giraud, Gnedin, Gorski, Governato, Gunn, Gunn, Hernquist, Huchra, Hudson, Jacoby, Kahn, Kaiser, Karachentsev, Katz, Katz, Kauffmann, Kauffmann, Kochanek, Kraan-Korteweg, Kroeker, Lacey, Ma, Marzke, Mo, Moore, Moore, Moore, Moscardini, Nusser, Ostriker, Oukbir, Peebles, Peebles, Peebles, Rees, Sandage, Schlegel, Shaya, Silk, Somerville, Somerville, Strauss, Subramanian, Villumsen, White, Yahil, Yahil, Zhang   +74 more
core   +3 more sources

Exploring the Structures and Substructures of the Andromeda Satellite Dwarf Galaxies Cassiopeia III, Perseus I, and Lacerta I

The Astronomical Journal, 2023
We present results from wide-field imaging of the resolved stellar populations of the dwarf spheroidal galaxies Cassiopeia III (And XXXII) and Perseus I (And XXXIII), two satellites in the outer stellar halo of the Andromeda galaxy (M31).
Katherine L. Rhode, Nicholas J. Smith, Denija Crnojevic, David J. Sand, Ryan A. Lambert, Enrico Vesperini, Madison V. Smith, Steven Janowiecki, John J. Salzer, Ananthan Karunakaran, Kristine Spekkens   +10 more
doaj   +1 more source

Disk Heating, Galactoseismology, and the Formation of Stellar Halos [PDF]

, 2017
Deep photometric surveys of the Milky Way have revealed diffuse structures encircling our Galaxy far beyond the "classical" limits of the stellar disk. This paper reviews results from our own and other observational programs, which together suggest that,
Beaton, Rachael S., Bergemann, Maria, Johnston, Kathryn V., Laporte, Chervin, Li, Ting S., Majewski, Steven R., Price-Whelan, Adrian M., Sesar, Branimir, Sharma, Sanjib, Sheffield, Allyson A.   +9 more
core   +5 more sources

Gamma-Rays from Dark Matter Mini-Spikes in M31

, 2007
The existence of a population of wandering Intermediate Mass Black Holes (IMBHs) is a generic prediction of scenarios that seek to explain the formation of Supermassive Black Holes in terms of growth from massive seeds.
Gianfranco Bertone, J. J. Geehan, Marco Taoso, Mattia Fornasa   +3 more
core   +2 more sources

Dust around Massive Stars Is Agnostic to Galactic Environment: New Insights from PHAT/BEAST

The Astrophysical Journal
Resolving the environments of massive stars is crucial for understanding their formation mechanisms and their impact on galaxy evolution. An important open question is whether massive stars found in diffuse regions outside spiral arms formed in situ or ...
Christina Willecke Lindberg, Claire E. Murray, Julianne J. Dalcanton, J. E. G. Peek, Karl D. Gordon   +4 more
doaj   +1 more source