Results 61 to 70 of about 193,103 (196)

Tracing the Contribution of Abiotic Methane in Deep Natural Gases From the Songliao Basin, China Using Bulk Isotopes and Methane Clumped Isotopologue 12CH2D2

Geochemistry, Geophysics, Geosystems, Volume 26, Issue 4, April 2025.
Abstract The identification and evaluation of abiotic methane remain an active research area due to uncertainties in traditional indicators that may lead to “false‐positive” detections. As an emerging isotopic tool, methane clumped isotope can provide novel information about the generation and post‐generation processes of methane gases.
Jiacheng Li, Qingmei Liu, Wenmin Jiang, Yun Li, Yanhua Shuai, Yongqiang Xiong   +5 more
wiley   +1 more source

A Unified Treatment of Kepler Occurrence to Trace Planet Evolution. II. The Radius Cliff Formed by Atmospheric Escape

The Astronomical Journal
The Kepler mission enabled us to look at the intrinsic population of exoplanets within our galaxy. In period-radius space, the distribution of the intrinsic population of planets contains structure that can trace planet formation and evolution history ...
Anne Dattilo, Natalie M. Batalha
doaj   +1 more source

Planetary Parameters, XUV Environments, and Mass-loss Rates for Nearby Gaseous Planets with X-Ray-detected Host Stars

The Astronomical Journal, 2023
We leverage Gaia DR2 parallactic distances to deliver new or revised estimates of planetary parameters and X-ray irradiation for a distance-limited (≲100 pc) sample of 27 gaseous planets (from super-Earths to hot Jupiters) with publicly available Chandra
Riccardo Spinelli, Elena Gallo, Francesco Haardt, Andrea Caldiroli, Federico Biassoni, Francesco Borsa, Emily Rauscher   +6 more
doaj   +1 more source

Thermophysical States of MgSiO3 Liquid up to Terapascal Pressures: Implications for Magma Oceans in Super‐Earths and Sub‐Neptunes

Journal of Geophysical Research: Planets, Volume 130, Issue 4, April 2025.
Abstract Thermophysical properties of silicate liquids under extreme conditions are critical for understanding the accretion and evolution of super‐Earths and sub‐Neptunes. The thermal equation of state and viscosity of silicate liquids determine the adiabatic profiles and dynamics of magma oceans. However, these properties are challenging to constrain
Haiyang Luo, Jie Deng
wiley   +1 more source

A High-resolution Non-detection of Escaping Helium in the Ultrahot Neptune LTT 9779b: Evidence for Weakened Evaporation

The Astrophysical Journal Letters
The recent discovery of “ultrahot” ( P < 1 day) Neptunes has come as a surprise: some of these planets have managed to retain gaseous envelopes despite being close enough to their host stars to trigger strong photoevaporation and/or Roche lobe overflow ...
Shreyas Vissapragada, Patrick McCreery, Leonardo A. Dos Santos, Néstor Espinoza, Andrew McWilliam, Noriyuki Matsunaga, Jéa Adams Redai, Patrick Behr, Kevin France, Satoshi Hamano, Charlie Hull, Yuji Ikeda, Haruki Katoh, Hideyo Kawakita, Mercedes López-Morales, Kevin N. Ortiz Ceballos, Shogo Otsubo, Yuki Sarugaku, Tomomi Takeuchi   +18 more
doaj   +1 more source

A New Set of Atmosphere and Evolution Models for Brown Dwarfs and Giant Exoplanets

, 2019
The study of brown dwarfs and giant exoplanets is rapidly evolving as ever-improving instrumentation becomes sensitive to cooler objects. Accurate and reliable atmosphere and evolutionary models are important for placing mass and age constraints on these newly discovered objects, and understanding the rich chemistry and physics taking place in their ...
Mark W Phillips, Pascal Tremblin, Isabelle Baraffe, Gilles Chabrier   +3 more
openaire   +2 more sources

MESSENGER Observations of a Possible Alfvén Wing at Mercury Driven by a Low Alfvénic Mach Number Interplanetary Coronal Mass Ejection

Journal of Geophysical Research: Space Physics, Volume 130, Issue 3, March 2025.
Abstract We investigate Mercury's response to rare, low Alfvénic Mach number MA $\left({M}_{A}\right)$ solar wind conditions using observations from the Mercury Surface, Space Environment, Geochemistry, and Ranging (MESSENGER) mission. This study provides compelling evidence of Mercury's altered magnetospheric state under these extreme conditions ...
Charles F. Bowers, Caitríona M. Jackman, Xianzhe Jia, James A. Slavin, Joachim Saur, Mika K. G. Holmberg, Ryan M. Dewey, Daniel Heyner, Filip Elekes, Lina Z. Hadid, Benoit Lavraud, Yang Wang, Hans L. F. Huybrighs, Matthew J. Rutala, Alexandra R. Fogg, Stephenie Brophy Lee, Daragh M. Hollman   +16 more
wiley   +1 more source

Atmospheric Regimes and Trends on Exoplanets and Brown Dwarfs [PDF]

, 2020
A planetary atmosphere is the outer gas layer of a planet. Besides its scientific significance among the first and most accessible planetary layers observed from space, it is closely connected with planetary formation and evolution, surface and interior processes, and habitability of planets.
arxiv   +1 more source

Is OSSO a Significant Contributor to the Unknown UV Absorber in Venus' Atmosphere?

Geophysical Research Letters, Volume 52, Issue 4, 28 February 2025.
Abstract It has been proposed that two isomers of the SO dimer (cis‐ and trans‐OSSO) are candidates for the unknown UV absorber in Venus' atmosphere because they have a good spectral match with the absorber, despite the low concentrations predicted by 1D photochemical models.
Joanna V. Egan, Wuhu Feng, Alexander D. James, James Manners, Daniel R. Marsh, Sébastien Lebonnois, Franck Lefèvre, Aurélien Stolzenbach, John M. C. Plane   +8 more
wiley   +1 more source

Superhabitable Planets Around Mid‐Type K Dwarf Stars Enhance Simulated JWST Observability and Surface Habitability

Astronomische Nachrichten, Volume 346, Issue 2, February 2025.
ABSTRACT In our search for life beyond the Solar System, certain planetary bodies may be more conducive to life than Earth. However, the observability of these “superhabitable” (SH) planets in the habitable zones around K dwarf stars has not been fully modeled. This study addresses this gap by modeling the atmospheres of SH exoplanets.
Iva Vilović, Jayesh Goyal, René Heller, Fanny Marie von Schauenburg   +3 more
wiley   +1 more source