Results 41 to 50 of about 4,002,507 (183)

Chemical and kinematical evolution in nearby dwarf spheroidal galaxies [PDF]

, 2006
Dwarf spheroidal (dSph) galaxies are the least massive and luminous objects known to exist. These galaxies are often considered as the fossil building blocks of massive systems predicted by some cosmological models.
Koch, Andreas
core   +1 more source

The ORCA‐TWIN qCMOS Experiment I. Science Case and Commissioning at Calar Alto Observatory

Astronomische Nachrichten, Volume 347, Issue 7, August 2026.
ABSTRACT We describe a pilot study to explore a new generation of fast and low noise CMOS image sensors for time domain astronomy, using two remote telescopes with a baseline of 1635 km. The experiment involves direct imaging with novel qCMOS image sensor technology that combines fast readout with sub‐electron readout noise.
Martin M. Roth, Paško Roje, Stella Vješnica, Stefan Cikota, Alex J. Brown, Mike Kretlow, Marco Azzaro, Santiago Reinhart, Jesús Aceituno, Harry Dawson, Carsten Denker, Torsten Enßlin, Stephan Geier, Thomas Granzer, Thomas Kupfer, Gianluca Li Causi, Samaya Nissanke, José Luis Ortiz, Fernando Pedichini, Katja Poppenhäger, Axel Schwope   +20 more
wiley   +1 more source

Rising Near-ultraviolet Spectra in Stellar Megaflares

The Astrophysical Journal
Flares from M dwarf stars can attain energies up to 10 ^4 times larger than solar flares but are generally thought to result from similar processes of magnetic energy release and particle acceleration.
Adam F. Kowalski, Rachel A. Osten, Yuta Notsu, Isaiah I. Tristan, Antigona Segura, Hiroyuki Maehara, Kosuke Namekata, Shun Inoue   +7 more
doaj   +1 more source

A New Pencil‐Tailed Tree Mouse Chiropodomys wandingensis sp. nov. (Rodentia: Muridae) From Yunnan, China

Ecology and Evolution, Volume 16, Issue 7, July 2026.
The genus Chiropodomys has seen no new species described since the 1980s. Through integrated morphological and molecular analysis, a specimen from Yunnan, China, is identified as a distinct new species, C. wandingensis sp. nov., supported by significant genetic divergence from its closest relatives.
Yi‐shun Qian, Xin Mou, Shuo Liu, Song Li   +3 more
wiley   +1 more source

Flaring Activity for Low-mass Stars in the β Pictoris Moving Group

The Astronomical Journal
Stellar flares from K and M dwarfs release panchromatic radiation characterized by a significantly higher brightness temperature (∼9–20 kK) than the star. The increased frequency of magnetic activity on young low-mass stars results in the energy released
Jordan N. Ealy, Joshua E. Schlieder, Thaddeus D. Komacek, Emily A. Gilbert   +3 more
doaj   +1 more source

Searching for Rotational X‐Ray Modulation on TIC 277539431

Astronomische Nachrichten, Volume 347, Issue 3, March 2026.
ABSTRACT TIC 277539431, a fast rotating M7 dwarf, was detected to host the highest latitude flare to date at 81°$$ {81}^{{}^{\circ}} $$. Magnetic activity like stellar flares occurring at high latitude indicate occurrence of coronal loops at these latitudes on fully‐convective M dwarfs. In contrast, sunspots usually occur below 30°$$ {30}^{{}^{\circ}} $
Desmond Dsouza, Katja Poppenhäger, Ekaterina Ilin   +2 more
wiley   +1 more source

A Seven-day Multiwavelength Flare Campaign on AU Mic. III. Quiescent and Flaring Properties of the X-Ray Spectra and Chromospheric Lines

The Astrophysical Journal
We present the X-ray quiescent and flaring properties from a unique, 7 days multiwavelength observing campaign on the M1 flare star AU Mic. Combining the XMM-Newton X-ray spectra with the chromospheric line and broadband near-UV (NUV) and optical ...
Yuta Notsu, Isaiah I. Tristan, Rachel A. Osten, Alexander Brown, Adam F. Kowalski, Carol A. Grady   +5 more
doaj   +1 more source

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, Weihao Liu, Jingnan Guo, Mikhail Dobynde, Robert F. Wimmer‐Schweingruber   +4 more
wiley   +1 more source

First Temperature Profile of a Stellar Flare Using Differential Chromatic Refraction

The Astrophysical Journal Letters
We present the first derivation of a stellar flare temperature profile from single-band photometry. Stellar flare DWF 030225.574−545707.45129 was detected in 2015 by the Dark Energy Camera as part of the Deeper, Wider, Faster program. The brightness (Δ m
Riley W. Clarke, Federica Bianco, James R. A. Davenport, Jeffery Cooke, Sara Webb, Igor Andreoni, Tyler Pritchard, Aaron Roodman   +7 more
doaj   +1 more source

New flare stars and flares of the known ones in Orion

, 2016
Observations of red dwarf flare stars were initiated in the Abastumani Astrophysical Observatory in 1969 (Kiladze, 1972). Regions rich in red dwarf stars were selected: the area around Orion Trapezium, and the stellar cluster of Pleiades have been chosen ...
R. Natsvlishvili, I. Kochiashvili, N. Kochiashvili   +2 more
semanticscholar   +1 more source