Results 91 to 100 of about 2,624,667 (213)
AGU Advances, Volume 6, Issue 2, April 2025.Abstract Characterizing the evolution of drought frequency and severity under anthropogenic global warming remains a key challenge because of the mismatch between the length of instrumental records and the long‐term variability of drought features.
Rui Guo +4 more
wiley +1 more source
The South African Astronomical Observatory [PDF]
Topics discussed in the Overview of Year 1988 include the following: Supernova in the Large Magellanic Cloud; Galaxies; Ground based observations of celestial x ray sources; the Magellanic Clouds; Pulsating variables; Galactic structure; Binary star ...
core +1 more source
Stellar evolution and modelling stars
, 2017 In this chapter I give an overall description of the structure and evolution of stars of different masses, and review the main ingredients included in state-of-the-art calculations aiming at reproducing observational features.
A. Bressan +84 more
core +1 more source
Distances and Stellar Population properties using the SBF method [PDF]
arXiv, 2008 We present some results on the study of stellar population properties and distances of galaxies using the SBF technique. The applications summarized here show that the Surface Brightness Fluctuations (SBF) method is able to i) provide accurate distances of resolved and unresolved stellar systems from ~10 Kpc to ~150 Mpc, and ii) to reliably constrain ...
arxiv
The Need for Better Monitoring of Climate Change in the Middle and Upper Atmosphere
AGU Advances, Volume 6, Issue 2, April 2025.Abstract Anthropogenic greenhouse gas emissions significantly impact the middle and upper atmosphere. They cause cooling and thermal shrinking and affect the atmospheric structure. Atmospheric contraction results in changes in key atmospheric features, such as the stratopause height or the peak ionospheric electron density, and also results in reduced ...
Juan A. Añel +13 more
wiley +1 more source
Elemental ratios in stars vs planets
, 2015 Context. The chemical composition of planets is an important constraint for planet formation and subsequent differentiation. While theoretical studies try to derive the compositions of planets from planet formation models in order to link the composition
Alibert, Yann +4 more
core +1 more source
High‐Speed Electron Flows in the Earth Magnetotail
AGU Advances, Volume 6, Issue 2, April 2025.Abstract High‐speed electron flows (HSEFs) play a crucial role in the energy dissipation and conversion processes within the terrestrial magnetosphere and can drive various types of plasma waves and instabilities, affecting the electron‐scale dynamics.
Huijie Liu +20 more
wiley +1 more source
Jets (relativistic and non) in astrophysics [PDF]
arXiv, 2010 Let's take stock of the situation on one of the most studied astrophysical phenomena during the latest years: the jets escaping from protostars, stellar singularities, GRB and active galactic nuclei.
arxiv
Journal of Geophysical Research: Space Physics, Volume 130, Issue 4, April 2025.Abstract While whistler‐mode waves are generated by injected anisotropic electrons on the nightside, the observed day‐night asymmetry of wave distributions raises an intriguing question about their generation on the dayside. In this study, we evaluate the distributions of whistler‐mode wave amplitudes and electrons as a function of distance from the ...
Y. Peng, W. Li, Q. Ma, X.‐C. Shen
wiley +1 more source
Cluster Observations of Plasma in the High Latitude Magnetotail Associated With Cusp‐Aligned Arcs
Journal of Geophysical Research: Space Physics, Volume 130, Issue 4, April 2025.Abstract During periods of northward interplanetary magnetic field (IMF), the magnetospheric structure and dynamics are dramatically different compared to the southward IMF case. Previous studies using both observations and simulations have shown that under northward IMF the magnetotail becomes dominated by closed magnetic flux and associated trapped ...
M. K. Mooney +5 more
wiley +1 more source