Results 81 to 90 of about 468,207 (173)

Chemical Timescales in the Atmospheres of Highly Eccentric Exoplanets [PDF]

, 2012
Close-in exoplanets with highly eccentric orbits are subject to large variations in incoming stellar flux between periapse and apoapse. These variations may lead to large swings in atmospheric temperature, which in turn may cause changes in the chemistry of the atmosphere from higher CO abundances at periapse to higher CH4 abundances at apoapse.
arxiv   +1 more source

Shock Compression of Coesite up to 950 GPa

Geophysical Research Letters, Volume 51, Issue 24, 28 December 2024.
Abstract Experimental investigations of silica under high pressure and temperature offer crucial insights into modeling of Earth and super‐Earths’ interiors. Despite extensive studies on Hugoniots of silica polymorphs like fused‐silica (2.20 g/cm3), quartz (2.65 g/cm3) and stishovite (4.29 g/cm3) up to a terapascal, unexplored region of melting and ...
Xiaokang Feng, Kento Katagiri, Jia Qu, Keita Nonaka, Liang Sun, Pinwen Zhu, Norimasa Ozaki, Takayoshi Sano, Toshimori Sekine, Wenge Yang   +9 more
wiley   +1 more source

Recovering the colour-dependent albedo of exoplanets with high-resolution spectroscopy: from ESPRESSO to the ELT [PDF]

, 2018
The characterization of planetary atmospheres is a daunting task, pushing current observing facilities to their limits. The next generation of high-resolution spectrographs mounted on large telescopes -- such as ESPRESSO@VLT and HIRES@ELT -- will allow us to probe and characterize exoplanetary atmospheres in greater detail than possible to this point ...
arxiv   +1 more source

The Process We Call Earth: Relationships Between Dynamic Feedbacks and the Search for Gaiasignatures in a New Paradigm of Earthlikeness

Perspectives of Earth and Space Scientists, Volume 5, Issue 1, December 2024.
Abstract Standard notions of an “Earthlike” planet rely solely on physical and material properties, like planetary mass, radius, and surface temperature. Here, we introduce a novel, relational perspective on what defines “Earthlikeness.” In our process‐based framework, rocky planets are local pockets of free energy that have the potential to drive the ...
Michael L. Wong, Marissa Duckett, Emilia S. Hernandez, Vahab Rajaei, Kayla J. Smith   +4 more
wiley   +1 more source

Eclipse Mapping with MIRI: 2D Map of HD 189733b from 8 μm JWST MIRI LRS Observations

The Astrophysical Journal Letters
Observations and models of transiting hot Jupiter exoplanets indicate that atmospheric circulation features may cause large spatial flux contrasts across their daysides.
Maura Lally, Ryan C. Challener, Nikole K. Lewis, Julie Inglis, Tiffany Kataria, Heather A. Knutson, Brian M. Kilpatrick, Natasha E. Batalha, Paul Bonney, Ian J. M. Crossfield, Trevor Foote, Gregory W. Henry, David K. Sing, Kevin B. Stevenson, Hannah R. Wakeford, Robert T. Zellem   +15 more
doaj   +1 more source

Simultaneous Infrared Observations of the Jovian Auroral Ionosphere and Thermosphere

Journal of Geophysical Research: Space Physics, Volume 129, Issue 12, December 2024.
Abstract Simultaneous observations of H3+ ${\mathrm{H}}_{3}^{+}$ and H2 ${\mathrm{H}}_{2}$ in Jupiter's northern infrared aurora were conducted on 02 June 2017 using Keck‐NIRSPEC to produce polar projection maps of H3+ ${\mathrm{H}}_{3}^{+}$ radiance, rotational temperature, column density, and H2 ${\mathrm{H}}_{2}$ radiance. The temperature variations
Ruoyan Wang, Tom S. Stallard, Henrik Melin, Kevin H. Baines, Luke Moore, James O’Donoghue, Rosie E. Johnson, Emma M. Thomas, Katie L. Knowles, Paola I. Tiranti, Steve Miller   +10 more
wiley   +1 more source

A Direct Comparison between the Use of Double Gray and Multiwavelength Radiative Transfer in a General Circulation Model with and without Radiatively Active Clouds

The Astrophysical Journal
Inhomogeneous cloud formation and wavelength-dependent phenomena are expected to shape hot Jupiter atmospheres. We present a general circulation model with multiwavelength “picket fence” radiative transfer and radiatively active, temperature-dependent ...
Isaac Malsky, Emily Rauscher, Michael T. Roman, Elspeth K. H. Lee, Hayley Beltz, Arjun Savel, Eliza M.-R. Kempton, L. Cinque   +7 more
doaj   +1 more source

Magma Ocean Evolution at Arbitrary Redox State

Journal of Geophysical Research: Planets, Volume 129, Issue 12, December 2024.
Abstract Interactions between magma oceans and overlying atmospheres on young rocky planets leads to an evolving feedback of outgassing, greenhouse forcing, and mantle melt fraction. Previous studies have predominantly focused on the solidification of oxidized Earth‐similar planets, but the diversity in mean density and irradiation observed in the low ...
Harrison Nicholls, Tim Lichtenberg, Dan J. Bower, Raymond Pierrehumbert   +3 more
wiley   +1 more source

Analogous response of temperate terrestrial exoplanets and Earth's climate dynamics to greenhouse gas supplement [PDF]

arXiv, 2023
Humanity is close to characterizing the atmospheres of rocky exoplanets due to the advent of JWST. These astronomical observations motivate us to understand exoplanetary atmospheres to constrain habitability. We study the influence greenhouse gas supplement has on the atmosphere of TRAPPIST-1e, an Earth-like exoplanet, and Earth itself by analyzing ...
arxiv  

Solar Wind Power Likely Governs Uranus' Thermosphere Temperature

Geophysical Research Letters, Volume 51, Issue 22, 28 November 2024.
Abstract Observations of Uranus in the near‐infrared by ground‐based telescopes from 1992 to 2018 have shown that the planet's upper atmosphere (thermosphere) steadily cooled from ∼700 to ∼450 K. We explain this cooling as due to the concurrent decline in the power of the solar wind incident on Uranus' magnetic field, which has dropped by ∼50% over the
A. Masters, J. R. Szalay, S. Zomerdijk‐Russell, M. M. Kao   +3 more
wiley   +1 more source