Results 71 to 80 of about 517 (155)

Effects of the three-dimensional structure of hot exoplanet atmospheres on observations and retrieval models

, 2020
Nowdays, we are able to discover more and more exoplanets, and even more important we can observe their atmospheres and we are starting to get information on their physical, dynamic and, chemical properties. With the new generation of space telescopes such as the JWST or Ariel, we will be able to observe spectral features that are now unobservable ...
openaire   +1 more source

Thermal structure, composition, atmospheric dynamics and long-terme evolution of irradiated exoplanets

Structure thermique, composition, dynamique de l’atmosphère et évolution à long-terme des exoplanètes irradiées Plus d’un millier d’exoplanètes ont été découvertes depuis une dizaine d’années. Plus incroyable encore, nous pouvons maintenant caractériser les atmosphères de ces mondes lointains.
openaire   +2 more sources

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

Oxygen Left Behind: Atmospheric Enrichment Due to Fractionation in Sub-Neptunes Using BOREAS

The Astrophysical Journal
The evolution of exoplanetary atmospheres is strongly influenced by atmospheric escape, particularly for close-in planets. Fractionation during atmospheric loss can preferentially remove lighter elements such as hydrogen, while retaining heavier species ...
Marilina Valatsou, Caroline Dorn, Pierlou Marty, James E. Owen   +3 more
doaj   +1 more source

A Next-generation Exoplanet Atmospheric Retrieval Framework for Transmission Spectroscopy (NEXOTRANS): Comparative Characterization for WASP-39 b Using JWST NIRISS, NIRSpec PRISM, and MIRI Observations

The Astrophysical Journal
The advent of JWST has marked a new era in exoplanetary atmospheric studies, offering higher-resolution data and greater precision across a broader spectral range than previous space-based telescopes.
Tonmoy Deka, Tasneem Basra Khan, Swastik Dewan, Priyankush Ghosh, Debayan Das, Liton Majumdar   +5 more
doaj   +1 more source

A Comprehensive Sulfur Chemistry Network Including Excited S(1D) and SO(1Δ) for the XODIAC Photochemical Model: Accounting for Missing Sulfur Processes in Venus and Exo-Venus Analogs

The Astrophysical Journal
Sulfur chemistry plays a central role in controlling the atmospheric structure, cloud formation, and composition of Venus and Venus-like exoplanets. However, key reactions involving ground- and excited-state sulfur species remain poorly constrained, and ...
Priyankush Ghosh, Namrata Rani, Jeehyun Yang, Karen Willacy, P. B. Rimmer, Liton Majumdar   +5 more
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First Results from WINERED: Detection of Emission Lines from Neutral Iron and a Combined Set of Trace Species on the Dayside of WASP-189 b

The Astronomical Journal
Ground- and space-based observations have revealed that ultrahot Jupiters (UHJs, T _eq  > 2200 K) typically have inverted thermal profiles, while cooler hot Jupiters have noninverted ones.
Lennart van Sluijs, Emily Rauscher, Eliza M.-R. Kempton, Thomas Kennedy, Isaac Malsky, Noriyuki Matsunaga, Michael Meyer, Andrew McWilliam, John D. Monnier, Shogo Otsubo, Yuki Sarugaku, Tomomi Takeuchi   +11 more
doaj   +1 more source

Photochemical Hazes in Exoplanetary Skies with Diamonds: Microphysical Modeling of Haze Composition Evolution via Chemical Vapor Deposition

The Astrophysical Journal
Observational efforts in the last decade suggest the prevalence of photochemical hazes in exoplanetary atmospheres. Recent JWST observations raise growing evidence that exoplanetary hazes tend to have reflective compositions, unlike the conventionally ...
Kazumasa Ohno
doaj   +1 more source

3D Modeling of Moist Convective Inhibition in Idealized Sub-Neptune Atmospheres

The Astrophysical Journal
Atmospheric convection behaves differently in hydrogen-rich atmospheres compared to higher mean molecular weight atmospheres due to compositional gradients of tracers.
Namrah Habib, Raymond T. Pierrehumbert
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A Window for Water-hydrogen Demixing on Warm Metal-rich Sub-Neptunes

The Astrophysical Journal
Sub-Neptunes represent the largest exoplanet demographic, yet their bulk compositions remain poorly understood. Recent studies suggested that only very cold planets, such as Uranus and Neptune, could experience stratification of volatiles in their ...
Caroline Piaulet-Ghorayeb, Daniel P. Thorngren, Eliza M.-R. Kempton, Justin Lipper, Leslie Rogers, Fernanda Correa Horta, Shi Lin Sun   +6 more
doaj   +1 more source