Results 41 to 50 of about 1,022 (196)

Evidence for a Natural Limit to Electron Space Radiation: An Application of Benford's Law

Journal of Geophysical Research: Space Physics, Volume 130, Issue 10, October 2025.
Abstract Recent research has highlighted observational evidence for a natural limit to the severity of energetic electron differential fluxes in the Van Allen radiation belts. Here, we analyze the occurrence distributions of electron differential fluxes from the entire Van Allen Probes mission (2012–2019) to further investigate the energy dependence of
L. Olifer, I. R. Mann
wiley   +1 more source

The First Evidence of a Host Star Metallicity Cutoff in the Formation of Super-Earth Planets

The Astronomical Journal
Planet formation is expected to be severely limited in disks of low metallicity, owing to both the small solid mass reservoir and the low-opacity accelerating the disk gas dissipation.
Kiersten M. Boley, Jessie L. Christiansen, Jon Zink, Kevin Hardegree-Ullman, Eve J. Lee, Philip F. Hopkins, Ji Wang, Rachel B. Fernandes, Galen J. Bergsten, Sakhee Bhure   +9 more
doaj   +1 more source

Doppler Constraints on Planetary Companions to Nearby Sun-like Stars: An Archival Radial Velocity Survey of Southern Targets for Proposed NASA Direct Imaging Missions

The Astronomical Journal, 2023
Directly imaging temperate rocky planets orbiting nearby, Sun-like stars with a 6 m class IR/O/UV space telescope, recently dubbed the Habitable Worlds Observatory, is a high-priority goal of the Astro2020 Decadal Survey.
Katherine Laliotis, Jennifer A. Burt, Eric E. Mamajek, Zhexing Li, Volker Perdelwitz, Jinglin Zhao, R. Paul Butler, Bradford Holden, Lee Rosenthal, B. J. Fulton, Fabo Feng, Stephen R. Kane, Jeremy Bailey, Brad Carter, Jeffrey D. Crane, Elise Furlan, Crystal L. Gnilka, Steve B. Howell, Gregory Laughlin, Stephen A. Shectman, Johanna K. Teske, C. G. Tinney, Steven S. Vogt, Sharon Xuesong Wang, Robert A. Wittenmyer   +24 more
doaj   +1 more source

Ancient Mars Climate With a Polar Ocean and Ice Sheet Dynamics

Journal of Geophysical Research: Planets, Volume 130, Issue 10, October 2025.
Abstract In this article, we study the conditions required to maintain a stable ocean on Mars 3 Ga using a new suite of simulations. These simulations couple a 3D Global Climate Model with ocean dynamics and ice sheet flow. The model includes the main processes of the atmosphere/hydrosphere/cryosphere to investigate Mars' ancient climate.
Frédéric Schmidt, Michael J. Way, Aurélien Quiquet, Igor Aleinov, Christophe Dumas   +4 more
wiley   +1 more source

Gravity-sensitive Spectral Indices in Ultracool Dwarfs: Investigating Correlations with Metallicity and Planet Occurrence Using SpeX and Fire Observations

The Astronomical Journal
We present a near-infrared spectroscopic analysis (0.9–2.4 μ m) of gravity indices for 56 ultracool dwarfs (M5.5–L0), including exoplanet hosts SPECULOOS-2, SPECULOOS-3, and LHS 3154.
Fatemeh Davoudi, Benjamin V. Rackham, Julien de Wit, Jan Toomlaid, Michaël Gillon, Amaury H. M. J. Triaud, Adam J. Burgasser, Christopher A. Theissen   +7 more
doaj   +1 more source

Electrical Resistivity of Liquid Fe‐16S‐2Si up to 13 GPa With Implications for the Adiabatic Heat Flux Through the Core of Exoplanet TRAPPIST‐1h

Journal of Geophysical Research: Planets, Volume 130, Issue 10, October 2025.
Abstract Thermal convective processes in the liquid cores of terrestrial planetary bodies with the capacity to generate magnetic dynamos may be better characterized by thermal conductivity estimates of core conditions. The composition of the core of asteroid 4 Vesta as determined by geochemical studies of HED meteorites is used as an analog for the ...
E. M. Lenhart, W. Yong, R. A. Secco
wiley   +1 more source

Re‐Analysis of Pioneer Venus Data: Water, Iron Sulfate, and Sulfuric Acid are Major Components in Venus' Aerosols

Journal of Geophysical Research: Planets, Volume 130, Issue 9, September 2025.
Abstract We present a new and transformative composition for Venus' cloud aerosols using previously uncharacterized data acquired by the Pioneer Venus Large Probe, which descended through Venus' atmosphere in 1978. This aerosol composition was extracted by re‐analyzing data acquired by the Large Probe Neutral Mass Spectrometer (LNMS) and re‐evaluating ...
R. Mogul, M. Yu. Zolotov, M. J. Way, S. S. Limaye   +3 more
wiley   +1 more source

The PEPSI Exoplanet Transit Survey (PETS). II. A Deep Search for Thermal Inversion Agents in KELT-20 b/MASCARA-2 b with Emission and Transmission Spectroscopy

The Astronomical Journal, 2023
Recent observations have shown that the atmospheres of ultrahot Jupiters (UHJs) commonly possess temperature inversions, where the temperature increases with increasing altitude.
Marshall C. Johnson, Ji Wang, Anusha Pai Asnodkar, Aldo S. Bonomo, B. Scott Gaudi, Thomas Henning, Ilya Ilyin, Engin Keles, Luca Malavolta, Matthias Mallonn, Karan Molaverdikhani, Valerio Nascimbeni, Jennifer Patience, Katja Poppenhaeger, Gaetano Scandariato, Everett Schlawin, Evgenya Shkolnik, Daniela Sicilia, Alessandro Sozzetti, Klaus G. Strassmeier, Christian Veillet, Fei Yan   +21 more
doaj   +1 more source

The “Analogs for VENus' GEologically Recent Surfaces” (AVENGERS) Initiative: Using Terrestrial Analogs to Study Recent Volcano‐Tectonic Activity on Venus and Inform the Characterization of Terrestrial Exoplanets

Journal of Geophysical Research: Planets, Volume 130, Issue 9, September 2025.
Abstract Several missions to Venus have recently been selected for launch, opening a new era for the exploration of the planet. A key question these missions seek to address is whether Venus is geologically active today. Detecting active volcanism on Venus would contribute to a better understanding of volcanic and atmospheric processes on Earth.
P. D’Incecco, J. Filiberto, J. B. Garvin, G. N. Arney, S. A. Getty, E. Kohler, L. M. Zelenyi, L. V. Zasova, O. I. Korablev, M. A. Ivanov, J. W. Head, D. A. Gorinov, S. Bhattacharya, S. S. Bhiravarasu, D. Putrevu, I. López, R. Ghail, P. Mason, J. Brossier, C. Monaco, S. Branca, R. A. Corsaro, D. Trang, J. R. Crandall, N. Mari, M. Blackett, G. Komatsu, A. Kosenkova, I. Flynn, S. Aveni, N. Lang, B. J. Thomson, I. Pagano, S. Cassisi, G. Eggers, R. E. Ernst, H. El Bilali, T. Kremic, J. Lustig‐Yaeger, N. Izenberg, L. Bruzzone, M. El Yazidi, E. Ferroni, D. Coero Borga, C. Badia, S. Parisini, G. Fiasconaro, S. Cussini, M. Dolci, E. Brocato, G. Gallardo i Peres, N. Davidova, S. Kane, C. Ostberg, V. Ortega‐Ramos, G. Di Achille   +55 more
wiley   +1 more source

Estimating the Mass Escaping Rates of Radius-valley-spanning Planets in the TOI-431 System via X-Ray and Ultraviolet Evaporation

The Astrophysical Journal
The TOI-431 system has three close-in exoplanets, which gives an ideal lab to study gas escape. In this study, we measure the X-ray and ultraviolet luminosity for TOI-431 with XMM-Newton’s European Photon Imaging Camera-pn and Optical/UV Monitor ...
Xiaoming Jiang, Jonathan H. Jiang, Remo Burn, Zong-Hong Zhu   +3 more
doaj   +1 more source