Results 81 to 90 of about 193,103 (196)

JWST/NIRISS Reveals the Water-rich “Steam World” Atmosphere of GJ 9827 d

The Astrophysical Journal Letters
With sizable volatile envelopes but smaller radii than the solar system ice giants, sub-Neptunes have been revealed as one of the most common types of planet in the galaxy. While the spectroscopic characterization of larger sub-Neptunes (2.5–4 R _⊕ ) has
Caroline Piaulet-Ghorayeb, Björn Benneke, Michael Radica, Eshan Raul, Louis-Philippe Coulombe, Eva-Maria Ahrer, Daria Kubyshkina, Ward S. Howard, Joshua Krissansen-Totton, Ryan J. MacDonald, Pierre-Alexis Roy, Amy Louca, Duncan Christie, Marylou Fournier-Tondreau, Romain Allart, Yamila Miguel, Hilke E. Schlichting, Luis Welbanks, Charles Cadieux, Caroline Dorn, Thomas M. Evans-Soma, Jonathan J. Fortney, Raymond Pierrehumbert, David Lafrenière, Lorena Acuña, Thaddeus Komacek, Hamish Innes, Thomas G. Beatty, Ryan Cloutier, René Doyon, Anna Gagnebin, Cyril Gapp, Heather A. Knutson   +32 more
doaj   +1 more source

Understanding Exoplanet Atmospheres with UV Observations I: NUV and Blue/Optical [PDF]

arXiv, 2019
Much of the focus of exoplanet atmosphere analysis in the coming decade will be atinfrared wavelengths, with the planned launches of the James Webb Space Telescope (JWST) and the Wide-Field Infrared Survey Telescope (WFIRST). However, without being placed in the context of broader wavelength coverage, especially in the optical and ultraviolet, infrared
arxiv  

Ionospheric Conductances at the Giant Planets of the Solar System: A Comparative Study of Ionization Sources and the Impact of Meteoric Ions

Journal of Geophysical Research: Space Physics, Volume 130, Issue 1, January 2025.
Abstract The dynamics of giant planet magnetospheres is controlled by a complex interplay between their fast rotation, their interaction with the solar wind, and their diverse internal plasma and momentum sources. In the ionosphere, the Hall and Pedersen conductances are two key parameters that regulate the intensity of currents coupling the ...
Noé Clément, Yuki Nakamura, Michel Blanc, Yuxian Wang, Sariah Al Saati   +4 more
wiley   +1 more source

Metal-rich stars are less suitable for the evolution of life on their planets

Nature Communications, 2023
Atmospheric ozone and oxygen protect the terrestrial biosphere against harmful ultraviolet (UV) radiation. Here, we model atmospheres of Earth-like planets hosted by stars with near-solar effective temperatures (5300 to 6300 K) and a broad range of ...
Anna V. Shapiro, Christoph Brühl, Klaus Klingmüller, Benedikt Steil, Alexander I. Shapiro, Veronika Witzke, Nadiia Kostogryz, Laurent Gizon, Sami K. Solanki, Jos Lelieveld   +9 more
doaj   +1 more source

Shock Compression of Coesite up to 950 GPa

Geophysical Research Letters, Volume 51, Issue 24, 28 December 2024.
Abstract Experimental investigations of silica under high pressure and temperature offer crucial insights into modeling of Earth and super‐Earths’ interiors. Despite extensive studies on Hugoniots of silica polymorphs like fused‐silica (2.20 g/cm3), quartz (2.65 g/cm3) and stishovite (4.29 g/cm3) up to a terapascal, unexplored region of melting and ...
Xiaokang Feng, Kento Katagiri, Jia Qu, Keita Nonaka, Liang Sun, Pinwen Zhu, Norimasa Ozaki, Takayoshi Sano, Toshimori Sekine, Wenge Yang   +9 more
wiley   +1 more source

The Process We Call Earth: Relationships Between Dynamic Feedbacks and the Search for Gaiasignatures in a New Paradigm of Earthlikeness

Perspectives of Earth and Space Scientists, Volume 5, Issue 1, December 2024.
Abstract Standard notions of an “Earthlike” planet rely solely on physical and material properties, like planetary mass, radius, and surface temperature. Here, we introduce a novel, relational perspective on what defines “Earthlikeness.” In our process‐based framework, rocky planets are local pockets of free energy that have the potential to drive the ...
Michael L. Wong, Marissa Duckett, Emilia S. Hernandez, Vahab Rajaei, Kayla J. Smith   +4 more
wiley   +1 more source

Exoplanet Aeronomy: A Case Study of WASP-69 b’s Variable Thermosphere

The Astronomical Journal
Aeronomy, the study of Earth’s upper atmosphere and its interaction with the local space environment, has long traced changes in the thermospheres of Earth and other solar system planets to solar variability in the X-ray and extreme-ultraviolet ...
W. Garrett Levine, Shreyas Vissapragada, Adina D. Feinstein, George W. King, Aleck Hernandez, Lía Corrales, Michael Greklek-McKeon, Heather A. Knutson   +7 more
doaj   +1 more source

UV transit observations of EUV-heated expanded thermospheres of Earth-like exoplanets around M-stars: testing atmosphere evolution scenarios

Astrophysics and Space Science, 2011
The detection and investigation of EUV heated, extended and non-hydrostatic upper atmospheres around terrestrial exoplanets would provide important insights into the interaction of the host stars plasma environment as well as the evolution of Earth-type planets their atmospheres and possible magnetic environments.
V. Eybl, Helmut Lammer, Arnold Hanslmeier, J. Weingrill, J. Weingrill, Maxim L. Khodachenko, Manuel Güdel, Mats Holmström, Petra Odert, Martin Leitzinger, B. Dorner, Kristina G. Kislyakova, M. Xiang Grüß, Yu. N. Kulikov, Ansgar Reiners   +14 more
openaire   +3 more sources

Estimating the Possible Ion Heating Caused by Alfvén Waves at Venus

Journal of Geophysical Research: Space Physics, Volume 129, Issue 12, December 2024.
Abstract In the Earth's magnetosphere wave‐particle interaction is a major ion energization process, playing an important role for the atmospheric escape. A common type of ion heating is associated with low‐frequency broadband electric wave fields. For such waves the energy is not concentrated to a certain narrow frequency range and exhibits no peaks ...
G. Stenberg Wieser, M. André, H. Nilsson, N. Edberg, M. Persson, S. Rojas Mata, M. Mihalikova, H. Gunell, A. Bader, Y. Futaana   +9 more
wiley   +1 more source

Numerical Performance of Correlated-k Distribution Method in Atmospheric Escape Simulation

The Astrophysical Journal
Atmospheric escape is crucial to understanding the evolution of planets in and out of the solar system and to interpreting atmospheric observations. While hydrodynamic escape simulations have been actively developed incorporating detailed processes such ...
Yuichi Ito, Tatsuya Yoshida, Akifumi Nakayama   +2 more
doaj   +1 more source