Results 131 to 140 of about 6,507,263 (232)

X-Ray Flares of Sun-Like Young Stellar Objects and Their Effects on Protoplanetary Disks

, 2005
Astronomical observations of flares from analogs of the early Sun have the potential to give critical insights into the high energy irradiation environment of protoplanetary disks. Solar-mass young stellar objects are significantly more X-ray luminous than the typical low-mass T Tauri star.
Glassgold, A. E., Feigelson, E. D., Momtmerle, T., Wolk, S.   +3 more
openaire   +2 more sources

Detecting Stellar Coronal Mass Ejections via Coronal Dimming in the Extreme Ultraviolet

The Astrophysical Journal
Stellar flares and coronal mass ejections (CMEs) can strip planetary atmospheres, reducing the potential habitability of terrestrial planets. While flares have been observed for decades, stellar CMEs remain elusive.
James Paul Mason, Allison Youngblood, Kevin France, Astrid M. Veronig, Meng Jin   +4 more
doaj   +1 more source

Unraveling the Evolution of Silicic Volcanism in a Distributed Volcanic Field: Insights From Harrat Khaybar, Western Saudi Arabia

Geochemistry, Geophysics, Geosystems, Volume 27, Issue 10, October 2026.
Abstract Distributed basaltic volcanic fields commonly host minor but significant silicic magmas, the origin of which remains debated. At Harrat Khaybar (western Saudi Arabia; ca. 1.7 Ma to present), volcanic activity erupted compositions range from alkali olivine basalt to trachyte and comendite.
Abdullah Alohali, Shanaka de Silva, Charles Lewis, Suhail S. Alhejji, Shane J. Cronin, Chris J. Russo   +5 more
wiley   +1 more source

Multiwavelength Study of a Superflare on RS CVn–Type Star HD 22468 Triggered at Hard X-Ray by SVOM

The Astrophysical Journal
Detection of stellar flares at hard X-ray is still rare at the current stage. A transient was recently detected by the hard X-ray camera ECLAIRs on board the SVOM mission at 11:39:01.2 UT on 2025 January 09. Simultaneous monitoring in the optical band on
J. Wang, W. J. Xie, F. Cangemi, A. Coleiro, H. L. Li, Y. Xu, X. H. Han, H. Yang, L. P. Xin, X. Mao, J. Zheng, J. J. Jin, G. W. Li, J. Rodriguez, L. Tao, B. Cordier, J. Y. Wei, P. Bacon, N. Bellemont, L. Bouchet, H. B. Cai, C. Cavet, Z. G. Dai, O. Godet, A. Goldwurm, S. Guillot, L. Huang, M. H. Huang, N. Jiang, E. W. Liang, X. M. Lu, S. Schanne, S. Le Stum, Y. L. Qiu, X. G. Wang, X. Y. Wang, C. Wu, L. Zhang, S. N. Zhang, S. J. Zheng   +39 more
doaj   +1 more source

Subduction Recycling and Closure of the Paleo‐Asian Ocean in the Beishan Orogen: Constraints From the Niujuanzi Ophiolitic Mélange and Associated Intrusions

Geochemistry, Geophysics, Geosystems, Volume 27, Issue 10, October 2026.
Abstract Ophiolitic mélanges and associated intrusions provide key archives for reconstructing the evolution of ancient ocean basins and subduction‐related mantle modification. The Hongliuhe–Niujuanzi–Xichangjing ophiolitic mélange in the central Beishan Orogen preserves important records of the Paleo‐Asian Ocean, but the timing of oceanic subduction ...
Yujia Song, Xijun Liu, Yao Xiao, Honghu Zeng, Pengde Liu   +4 more
wiley   +1 more source

Apache Point Observatory (APO)/SMARTS Flare Star Campaign Observations. I. Blue Wing Asymmetries in Chromospheric Lines during Mid-M-Dwarf Flares from Simultaneous Spectroscopic and Photometric Observation Data

The Astrophysical Journal
We conducted the time-resolved simultaneous optical spectroscopic and photometric observations of mid-M-dwarf flare stars YZ CMi, EV Lac, and AD Leo. Spectroscopic observations were obtained using Apache Point Observatory 3.5 m and Small and Moderate ...
Yuta Notsu, Adam F. Kowalski, Hiroyuki Maehara, Kosuke Namekata, Kenji Hamaguchi, Teruaki Enoto, Isaiah I. Tristan, Suzanne L. Hawley, James R. A. Davenport, Satoshi Honda, Kai Ikuta, Shun Inoue, Keiichi Namizaki, Daisaku Nogami, Kazunari Shibata   +14 more
doaj   +1 more source

Role of Post‐Collisional Magmatism in Continental Growth and Reworking Since the Late Archean

Geochemistry, Geophysics, Geosystems, Volume 27, Issue 10, October 2026.
Abstract The mechanisms responsible for the formation and compositional evolution of continental crust remain central questions in Earth science. Post‐collisional magmatism is widely preserved in the continental record; however, its contribution to crustal growth may be underestimated because enriched isotopic signatures obscure juvenile mantle input ...
Dongjian Ouyang, Ross N. Mitchell, Peng Peng, Jinghui Guo, Qiuli Li   +4 more
wiley   +1 more source

Multiwavelength Campaign Observations of a Young Solar-type Star, EK Draconis. II. Understanding Prominence Eruption through Data-driven Modeling and Observed Magnetic Environment

The Astrophysical Journal
EK Draconis, a nearby young solar-type star (G1.5V, 50–120 Myr), is known as one of the best proxies for inferring the environmental conditions of the young Sun.
Kosuke Namekata, Kai Ikuta, Pascal Petit, Vladimir S. Airapetian, Aline A. Vidotto, Petr Heinzel, Jiří Wollmann, Hiroyuki Maehara, Yuta Notsu, Shun Inoue, Stephen Marsden, Julien Morin, Sandra V. Jeffers, Coralie Neiner, Rishi R. Paudel, Antoaneta A. Avramova-Boncheva, Keith Gendreau, Kazunari Shibata   +17 more
doaj   +1 more source

The Sun as an X-ray star

Astronomy & Astrophysics
Context. Stellar coronae are unresolved in X-rays, so inferences about their structure rely on spectral analysis. The Sun-as-an-X-ray-star (SaXS) approach uses the Sun as a spatially resolved template to interpret stellar spectra, but previous SaXS ...
Joseph W. M., Stelzer B., Orlando S., Klawin M.   +3 more
doaj   +1 more source

Features of Ground Level Enhancement (GLE #74) Event on 11 May 2024

Journal of Geophysical Research: Space Physics, Volume 131, Issue 10, October 2026.
Abstract Ground Level Enhancement (GLE #74) occurred on 11 May 2024 following an X5.8 solar flare from active region AR 13668 and the associated halo coronal mass ejection. The event was observed by both ground‐based neutron monitors (NMs) and space‐borne instruments and occurred during a deep Forbush decrease and one of the strongest geomagnetic ...
Alexander Mishev, Nicholas Larsen, Sergey Koldobskiy, Hishashi Hayakawa, Yusuke Ebihara, Ilya Usoskin   +5 more
wiley   +1 more source