Results 31 to 40 of about 5,332 (183)

Chemical gradients in the Milky Way from the RAVE data. II. Giant stars [PDF]

, 2014
We provide new constraints on the chemo-dynamical models of the Milky Way by measuring the radial and vertical chemical gradients for the elements Mg, Al, Si, Ti, and Fe in the Galactic disc and the gradient variations as a function of the distance from ...
Bienaymé, O., Boeche, C., Chiappini, C., Freeman, K., Gibson, B. K., Gilmore, G., Grebel, E. K., Just, A., Kordopatis, G., Munari, U., Navarro, J. F., Parker, Q. A., Piffl, T., Reid, W., Seabroke, G. M., Sharma, S., Siebert, A., Siviero, A., Steinmetz, M., Watson, F. G., Wyse, R. F. G., Wyse, R. F.G., Zwitter, T.   +22 more
core   +2 more sources

Model Choice Matters for Age Inference on the Red Giant Branch

The Astrophysical Journal
Galactic archaeology relies on accurate stellar parameters to reconstruct the Galaxy's history, including information on stellar ages. While the precision of data has improved significantly in recent years, stellar models used for age inference have not ...
Leslie M. Morales, Jamie Tayar, Zachary R. Claytor   +2 more
doaj   +1 more source

Magellanic System Stars Identified in SMACS J0723.3-7327 James Webb Space Telescope Early Release Observations Images

The Astrophysical Journal, 2023
We identify 71 distant stars in James Webb Space Telescope/NIRCam early release observations (ERO) images of the field of galaxy cluster SMACS J0723.3-7327 (SMACS 0723).
Jake Summers, Rogier A. Windhorst, Seth H. Cohen, Rolf A. Jansen, Timothy Carleton, Patrick S. Kamieneski, Benne W. Holwerda, Christopher J. Conselice, Nathan J. Adams, Brenda L. Frye, Jose M. Diego, Christopher N. A. Willmer, Rafael Ortiz III, Cheng Cheng, Alex Pigarelli, Aaron Robotham, Jordan C. J. D’Silva, Scott Tompkins, Simon P. Driver, Haojing Yan, Dan Coe, Norman Grogin, Anton M. Koekemoer, Madeline A. Marshall, Nor Pirzkal, Russell E. Ryan Jr.   +25 more
doaj   +1 more source

An unsupervised machine learning approach to iron meteorite classification

Meteoritics &Planetary Science, EarlyView.
Abstract Iron meteorites are usually classified manually using bivariate elemental plots. This study extends iron meteorite classification into multi‐element space. We present a computational method for the classification of iron meteorites by applying unsupervised machine learning using density‐based cluster analysis.
Louis‐Alexandre Lobanov, Hilary Downes
wiley   +1 more source

Scaling K2. VI. Reduced Small-planet Occurrence in High-galactic-amplitude Stars

The Astronomical Journal, 2023
In this study, we performed a homogeneous analysis of the planets around FGK dwarf stars observed by the Kepler and K2 missions, providing spectroscopic parameters for 310 K2 targets —including 239 Scaling K2 hosts—observed with Keck/HIRES.
Jon K. Zink, Kevin K. Hardegree-Ullman, Jessie L. Christiansen, Erik A. Petigura, Kiersten M. Boley, Sakhee Bhure, Malena Rice, Samuel W. Yee, Howard Isaacson, Rachel B. Fernandes, Andrew W. Howard, Sarah Blunt, Jack Lubin, Ashley Chontos, Daria Pidhorodetska, Mason G. MacDougall   +15 more
doaj   +1 more source

Building a Continental‐Scale Geodetic Network: The Plate Boundary Observatory (PBO)

Perspectives of Earth and Space Scientists, Volume 7, Issue 1, December 2026.
Abstract The Plate Boundary Observatory (PBO) transformed the use of geodesy in North America to study crustal deformation and plate boundary processes by establishing a continental‐scale, standardized, open‐access geodetic network. Built and operated by UNAVCO between 2003 and 2018 as part of the National Science Foundation (NSF)‐funded EarthScope ...
Emily E. Zawacki, Michael E. Jackson, Glen S. Mattioli, David J. Mencin, Karl Feaux, Donna J. Charlevoix   +5 more
wiley   +1 more source

SAGA: Stellar Abundances for Galactic Archaeology [PDF]

, 2012
A tutorial for the Stellar Abundances for Galactic Archaeology (SAGA) database is presented. This paper describes the outline of the database, reports the current status of the data compilation and known problems, and presents plans for future updates ...
Suda, Takuma
core   +1 more source

TESS Subgiant and Lower-red-giant Asteroseismology in the Continuous Viewing Zones

The Astrophysical Journal
Asteroseismology, the study of stellar oscillations, and stellar modeling both offer profound insights into the fundamental properties and evolution of stars.
Sophia Grusnis, Jamie Tayar, Diego Godoy-Rivera   +2 more
doaj   +1 more source

Exploring the Universe with Metal-Poor Stars

, 2011
The early chemical evolution of the Galaxy and the Universe is vital to our understanding of a host of astrophysical phenomena. Since the most metal-poor Galactic stars (with metallicities down to [Fe/H]\sim-5.5) are relics from the high-redshift ...
A Frebel, A Frebel, A Frebel, A Frebel, A Frebel, A Frebel, A Frebel, A Frebel, A Frebel, A Heger, A Heger, A Klypin, A Koch, A Koch, A McWilliam, A Stacy, AP Cooper, AS Font, B Moore, B Robertson, C Chiappini, D Carollo, D Geisler, DK Lai, DN Spergel, E Komatsu, E Starkenburg, E Tolstoy, EN Kirby, EN Kirby, EN Kirby, EN Kirby, G Besla, G Meynet, H Umeda, HN Li, I Iben, J Diemand, J Simmerer, JD Simon, JD Simon, JE Norris, JE Norris, JE Norris, JE Norris, JE Norris, JE Norris, JG Cohen, JG Cohen, JK Hollek, JL Johnson, JP Fulbright, JS Sobeck, KV Johnston, L Liu, L Searle, L Wisotzki, M Bergemann, M Geha, M Limongi, M McQuinn, M Shetrone, M Tafelmeyer, MS Bessell, N Christlieb, N Christlieb, N Iwamoto, N Tominaga, N Yoshida, O Zahn, PC Clark, PS Barklem, R Cayrel, R Lunnan, R Schneider, S Feltzing, SC Keller, SE Woosley, SG Ryan, SG Ryan, T Karlsson, T Schörk, T Shigeyama, T Suda, TC Beers, TC Beers, TH Greif, TH Greif, V Bromm, V Bromm, V Springel, V Springel, V Springel, W Aoki, W Aoki, W Aoki   +95 more
core   +1 more source

Subterranean environments contribute to three‐quarters of classified ecosystem services

Biological Reviews, Volume 101, Issue 3, Page 1582-1605, June 2026.
ABSTRACT Beneath the Earth's surface lies a network of interconnected caves, voids, and systems of fissures forming in rocks of sedimentary, igneous, or metamorphic origin. Although largely inaccessible to humans, this hidden realm supports and regulates services critical to ecological health and human well‐being.
Stefano Mammola, David Brankovits, Tiziana Di Lorenzo, Isabel R. Amorim, Raluca Ioana Bancila, Adrià Bellvert, Enrico Bernard, Anna Blomberg, Paulo A.V. Borges, Martina Cappelletti, Rodrigo Lopes Ferreira, Rosalina Gabriel, Diana M. P. Galassi, Laura Garzoli, Vasilis Gerovasileiou, Grant C. Hose, Kathryn L. Korbel, Simone Martino, Ana Z Miller, Nataša Mori, Veronica Nanni, Giuseppe Nicolosi, Mattia Saccò, Troy S. Sakihara, Marconi Souza Silva, Anne E. Tamalavage, Maja Zagmajster, Efraín Chávez, Christian Griebler, Pedro Cardoso, Alejandro Martínez   +30 more
wiley   +1 more source