Results 81 to 90 of about 58,632 (214)
The Constraint of Crewed Mars Missions Based on Current Radiation Dose Measurements
Space Weather, Volume 24, Issue 3, March 2026.Abstract Crewed missions to Mars will be a milestone of future space exploration programs. However, the absence of Earth's magnetic field leaves astronauts directly exposed to unattenuated energetic particles in deep space, primarily galactic cosmic rays (GCRs), resulting in significantly higher radiation levels and enhanced health risks. Understanding
Chao Zhang +4 more
wiley +1 more source
Abundance Ratios in Dwarf Elliptical Galaxies [PDF]
Proceedings of the International Astronomical Union, 2016 AbstractThe aim of this study is to determine abundance ratios and star formation histories (SFH) of dwarf ellipticals in the nearby Virgo cluster. We perform a stellar population analysis of 39 dEs and study them using index-index and scaling relations. We find an unusual behaviour where [Na/Fe] is under-abundant w.r.t.
Sen, Seyda +3 more
openaire +4 more sources
X-Ray Bright Active Galactic Nuclei in Local Dwarf Galaxies: Insights from eROSITA
The Astrophysical JournalAlthough supermassive black holes (SMBHs) reside in the heart of virtually every massive galaxy, it remains debated whether dwarf galaxies commonly host SMBHs. Because low-mass galaxies may retain memory of the assembly history of their black holes (BHs),
Andrea Sacchi +3 more
doaj +1 more source
Shock metamorphic effects in Itokawa phosphates: A comparison with megaregolith‐derived meteorites
Meteoritics &Planetary Science, Volume 61, Issue 3, Page 351-370, March 2026.Abstract Returned regolith samples from the asteroid Itokawa provide a unique opportunity to compare shock metamorphic effects in unconsolidated regolith materials with those preserved in lithified meteorites, that is, megaregolith. We analyzed four Itokawa particles (Ueda—RA‐QD02‐0519, Narahara—RA‐QD02‐0573, Domon—RA‐QD02‐0588, Ishiuchi—RX‐MD03‐0212 ...
E. Dobrică, A. N. Krot, A. J. Brearley
wiley +1 more source
Abundance ratios in dwarf elliptical galaxies [PDF]
Monthly Notices of the Royal Astronomical Society, 2017 We determine abundance ratios of 37 dwarf ellipticals (dEs) in the nearby Virgo cluster. This sample is representative of the early-type population of galaxies in the absolute magnitude range -19.0 < Mr < -16.0. We analyze their absorption line-strength indices by means of index-index diagrams and scaling relations and use the stellar population ...
Şen, Ş. +16 more
openaire +9 more sources
The mass of dwarf spheroidal galaxies and the missing satellite problem
, 2005 We present the results from a suite of N-body simulations of the tidal stripping of two-component dwarf galaxies comprising some stars and dark matter. We show that recent kinematic data from the local group dwarf spheroidal (dSph) galaxies suggests that
Evans, N. Wyn +4 more
core +1 more source
Astronomische Nachrichten, Volume 347, Issue 1, January 2026.ABSTRACT Isochrones, equal‐age curves, are widely used in astrophysics to estimate stellar ages. Classical stellar parameters are, however, very limited in their usability for main sequence stars because of their weak age‐dependence. Here, rotation period measurements provide complementary information.
David Gruner, Sydney A. Barnes
wiley +1 more source
Dwarf Galaxies and Cluster Environments
Proceedings of the International Astronomical Union, 2018 AbstractWe report an investigation of the properties of dwarf galaxies (Mr < -15) inside 26 clusters at z = 0.15 – 0.25, using the X-ray data from the Chandra archive, and optical images taken with Subaru Suprime-Cam. Our results include: 1. Investigation of the dwarf galaxy density distribution is sensitive to the background galaxies and the choice
Hashimoto, Y., Henry, J., Boehringer, H.
openaire +3 more sources
NGC 3627: a galaxy-dwarf collision? [PDF]
Astronomy & Astrophysics, 2012 8 pages, 6 figures, 5 tables.
Weżgowiec, Marek +2 more
openaire +3 more sources
The Open Journal of AstrophysicsI present the Local Volume Database (LVDB), a catalog of the observed properties of dwarf galaxies and star clusters in the Local Group and Local Volume.
Andrew B Pace
doaj +1 more source