Results 31 to 40 of about 1,040 (180)

Strong Fractionation of Deuterium and Helium in Sub-Neptune Atmospheres along the Radius Valley

The Astrophysical Journal
We simulate atmospheric fractionation in escaping planetary atmospheres using IsoFATE , a new open-source numerical model. We expand the parameter space studied previously to planets with tenuous atmospheres that exhibit the greatest helium and deuterium
Collin Cherubim, Robin Wordsworth, Renyu Hu, Evgenya Shkolnik   +3 more
doaj   +1 more source

Effect of Laboratory Reagents for Cleaning Modern Contamination on the δ15N Integrity of Nitrogen‐Poor Samples

Rapid Communications in Mass Spectrometry, Volume 40, Issue 19, 15 October 2026.
ABSTRACT Rationale Nitrogen isotope values have been widely used for tracing ancient biogeochemical processes, but contaminant‐sensitive materials, such as Precambrian sedimentary rocks, meteorites, or returned extraterrestrial samples, often have low nitrogen levels and are thus vulnerable to modern organic contamination.
Kunmanee Bubphamanee, Andrew Schauer, Roger Buick   +2 more
wiley   +1 more source

Exploring Warm Jupiter Migration Pathways with Eccentricities. I. Catalog of Uniform Keplerian Fits to Radial Velocities of 200 Warm Jupiters

The Astrophysical Journal Supplement Series
Giant planets are expected to predominantly form beyond the water-ice line and occasionally undergo inward migration. Unlike hot Jupiters, which can result from high-eccentricity tidal migration, warm Jupiters between 0.1 and 1 au (≈10–365 days) are in ...
Marvin Morgan, Brendan P. Bowler, Quang H. Tran, Robert A. Wittenmyer, Duncan J. Wright, George Zhou, Tyler R. Fairnington   +6 more
doaj   +1 more source

Leveraging Multimodal Large Language Models to Analyse Student Exploration Behaviours in Educational Game Environments

Journal of Computer Assisted Learning, Volume 42, Issue 4, August 2026.
ABSTRACT Background Video data provides rich opportunities to examine student behaviour in game‐based learning environments, capturing not only observable actions but also subtle indicators of cognitive engagement. However, traditional video analysis is labor‐intensive, and current applications of AI to this task are limited by models trained on ...
Yiqiu Zhou, Xiner Liu, Andres Felipe Zambrano, Luc Paquette, Amanda Barany, Jaclyn Ocumpaugh, Ryan S. Baker, Jeff Ginger   +7 more
wiley   +1 more source

Massive Rocky Planets May Suppress Deep Melting

AGU Advances, Volume 7, Issue 4, August 2026.
Abstract Melting properties of silicates are critical to understanding the thermal evolution of rocky planetary interiors. In the deep mantles of massive rocky planets, post‐post‐spinel Mg2SiO4 ${\text{Mg}}_{2}{\text{SiO}}_{4}$ is potentially one of the most abundant mineral phases, yet its melting behavior remains unconstrained. Here, we determine the
Donghao Zheng, Yihang Peng, Jie Deng
wiley   +1 more source

Stellar rotation and its connection to the evolution of hydrogen‐dominated atmospheres of exoplanets [PDF]

Astronomische Nachrichten, 2021
AbstractThe population of known low‐ to intermediate‐mass exoplanets shows a large spread in densities, which is believed to be due to the diversity of planetary atmospheres and thus controlled by planetary atmospheric mass loss. One of the main drivers of long‐term atmospheric escape is the absorption of high‐energy X‐ray + extreme ultraviolet (XUV ...
openaire   +2 more sources

Evidence for Low-level Dynamical Excitation in Near-resonant Exoplanet Systems

The Astronomical Journal, 2023
The geometries of near-resonant planetary systems offer a relatively pristine window into the initial conditions of exoplanet systems. Given that near-resonant systems have likely experienced minimal dynamical disruptions, the spin–orbit orientations of ...
Malena Rice, Xian-Yu Wang, Songhu Wang, Avi Shporer, Khalid Barkaoui, Rafael Brahm, Karen A. Collins, Andrés Jordán, Nataliea Lowson, R. Paul Butler, Jeffrey D. Crane, Stephen Shectman, Johanna K. Teske, David Osip, Kevin I. Collins, Felipe Murgas, Gavin Boyle, Francisco J. Pozuelos, Mathilde Timmermans, Emmanuel Jehin, Michaël Gillon   +20 more
doaj   +1 more source

The Complexity of Deep Aqueous Fluids in Planetary Ultramafic Mantles

Geochemistry, Geophysics, Geosystems, Volume 27, Issue 7, July 2026.
Abstract Planetary volatiles cycle through a planet's crust, mantle, and atmosphere, playing a crucial role in surface processes and habitability. Discussions of planetary volatiles traditionally focus on water, carbon, nitrogen, and sulfur, but fluids in contact with silicate rocks and ultramafic mantles can contain significant amounts of magnesium ...
Sophia E. Economon, Dimitri A. Sverjensky   +1 more
wiley   +1 more source

Helium Depletion in Escaping Atmospheres of Sub-Neptunes: A Signature of Primary-to-secondary Transition

The Astrophysical Journal
Short-period sub-Neptunes are common in extrasolar systems. These sub-Neptunes are generally thought to have primary atmospheres of protoplanetary-disk gas origin.
Issei Kobayashi, Hiroyuki Kurokawa, Laura Schaefer, Satoshi Okuzumi   +3 more
doaj   +1 more source

Interactions of Sublimated Frost With Volcanic Plumes: Modeling Io's SO2 Atmosphere Using the DSMC Method

Journal of Geophysical Research: Planets, Volume 131, Issue 7, July 2026.
Abstract Io's tenuous atmosphere consists primarily of sulfur dioxide (SO2 ${\text{SO}}_{2}$) with observed column densities of approximately 1016−1017 $1{0}^{16}-1{0}^{17}$ cm−2 ${\text{cm}}^{-2}$. However, it remains uncertain whether the sublimation of SO2 ${\text{SO}}_{2}$ surface frost or volcanic outgassing is the primary source of the SO2 ...
Leander Schlarmann, Audrey Vorburger, Tim Mosimann, Nicolas Thomas, Peter Wurz   +4 more
wiley   +1 more source