Results 1 to 10 of about 7,811,850 (120)

Thermoelastic Contraction as a Suppressor of Atmospheric Escape in Close-in Exoplanets

The Astrophysical Journal
The survival of volatile-rich atmospheres on close-in exoplanets challenges classical escape models. We identify a fully classical, interior-driven correction: thermoelastic contraction of the planetary mantle slightly increases the gravitational binding
L. Yıldız, D. Kaykı, E. Güdekli
doaj   +1 more source

The Role of Formation Location in Shaping Sulfur-, Nitrogen-, and Carbon-bearing Species in Super-Earth and Sub-Neptune Atmospheres

The Astrophysical Journal
Atmospheric compositions of sub-Neptunes and super-Earths are often interpreted as tracers of formation location relative to volatile ice lines. However, prolonged magma oceans can chemically equilibrate with primordial atmospheres and modify accreted ...
Aaron Werlen, Remo Burn, Caroline Dorn, Lukas Felix, Annika Salmi   +4 more
doaj   +1 more source

Helium Escape in Context: Comparative Signatures of Four Close-in Exoplanets

The Astrophysical Journal
Observations of escaping atmospheres on close-in exoplanets show a wide range in the strength and morphology of He I 10830 Å and H I absorption. Scaling relations attempt to link the He I signal to X-ray and UV irradiation, mass loss, and bulk planetary ...
Anna Ruth Taylor, Tommi T. Koskinen, Chenliang Huang, Anthony Arfaux, Panayotis Lavvas   +4 more
doaj   +1 more source

Nitrogen as a Tracer of Giant Planet Formation. II. Comprehensive Study of Nitrogen Photochemistry and Implications for Observing NH3 and HCN in Transmission and Emission Spectra

The Astrophysical Journal, 2023
Atmospheric nitrogen may provide important constraints on giant planet formation. Following our semianalytical work, we further pursue the relation between observable NH _3 and an atmosphere’s bulk nitrogen abundance by applying the photochemical ...
Kazumasa Ohno, Jonathan J. Fortney
doaj   +1 more source

A Panchromatic Characterization of the Evening and Morning Atmosphere of WASP-107 b: Composition and Cloud Variations, and Insight into the Effect of Stellar Contamination

The Astronomical Journal
Limb-resolved transmission spectroscopy has the potential to transform our understanding of exoplanetary atmospheres. By separately measuring the transmission spectra of the evening and morning limbs, these atmospheric regions can be individually ...
Matthew M. Murphy, Thomas G. Beatty, Everett Schlawin, Taylor J. Bell, Michael Radica, Thomas D. Kennedy, Nishil Mehta, Luis Welbanks, Michael R. Line, Vivien Parmentier, Thomas P. Greene, Sagnick Mukherjee, Jonathan J. Fortney, Kazumasa Ohno, Lindsey Wiser, Anastasia Triantafillides, Emily Rauscher, Isaac R. Edelman, Marcia J. Rieke   +18 more
doaj   +1 more source

Metal Oxide Clusters in Gas-giant Exoplanet Atmospheres

The Astrophysical Journal
This study investigates the thermal stability and absorption of metal oxide clusters in exoplanetary atmospheres. Utilizing our thermochemical data, we analyze eight distinct cluster families: magnesium oxide (MgO), silicon monoxide (SiO), titanium ...
Deepak Bisht, Christiane Helling, David Gobrecht, Ludmila Carone, Helena Lecoq-Molinos, Peter Woitke, Markus Aichhorn, Jan Philip Sindel, Amit Reza   +8 more
doaj   +1 more source

A Possible Metal-dominated Atmosphere below the Thick Aerosols of GJ 1214 b Suggested by Its JWST Panchromatic Transmission Spectrum

The Astrophysical Journal Letters
GJ 1214b is the archetype sub-Neptune for which thick aerosols have prevented us from constraining its atmospheric properties for over a decade. In this study, we leverage the panchromatic transmission spectrum of GJ 1214b established by the Hubble Space
Kazumasa Ohno, Everett Schlawin, Taylor J. Bell, Matthew M. Murphy, Thomas G. Beatty, Luis Welbanks, Thomas P. Greene, Jonathan J. Fortney, Vivien Parmentier, Isaac R. Edelman, Nishil Mehta, Marcia J. Rieke   +11 more
doaj   +1 more source

The Runaway Greenhouse Effect on Hycean Worlds

The Astrophysical Journal, 2023
Hycean worlds are a proposed subset of sub-Neptune exoplanets with substantial water inventories, liquid surface oceans, and extended hydrogen-dominated atmospheres favorable for habitability.
Hamish Innes, Shang-Min Tsai, Raymond T. Pierrehumbert   +2 more
doaj   +1 more source

Up, Up, and Away: Winds and Dynamical Structure as a Function of Altitude in the Ultrahot Jupiter WASP-76b

The Astrophysical Journal
Due to the unprecedented signal strengths offered by the newest high-resolution spectrographs on 10 m class telescopes, exploring the 3D nature of exoplanets is possible with an unprecedented level of precision.
Aurora Y. Kesseli, Hayley Beltz, Emily Rauscher, I. A. G. Snellen   +3 more
doaj   +1 more source

JWST Transmission Spectroscopy of HD 209458b: A Supersolar Metallicity, a Very Low C/O, and No Evidence of CH4, HCN, or C2H2

The Astrophysical Journal Letters
We present the transmission spectrum of the original transiting hot Jupiter HD 209458b from 2.3 to 5.1 μ m as observed with the NIRCam instrument on the James Webb Space Telescope (JWST). Previous studies of HD 209458b’s atmosphere have given conflicting
Qiao Xue, Jacob L. Bean, Michael Zhang, Luis Welbanks, Jonathan Lunine, Prune August   +5 more
doaj   +1 more source