Results 81 to 90 of about 590 (181)
Coupling the Secular Dynamical and Atmospheric Evolution of Close-in Exoplanets
This thesis plunges into the enigmatic formation of the hot Neptune desert, a sparsely populated region of exoplanetary demographics, by exploring the processes that shape close-in exoplanets. Central to this inquiry is the interplay between atmospheric evaporation and orbital migration, two pivotal mechanisms governing the evolution of planetary ...
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Blowin’ in the Nonisothermal Wind: Core-powered Mass Loss with Hydrodynamic Radiative Transfer
The Astrophysical JournalThe mass loss rates of planets undergoing core-powered escape are usually modeled using an isothermal Parker-type wind at the equilibrium temperature, T _eq .
William Misener +3 more
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Coupled Planetary Interior and Tidal Evolution
The Astrophysical JournalWe present a new planetary structure/thermal evolution model, designed for use in problems that couple orbital dynamics with planetary structure. We first benchmark our structural/thermal evolution calculations against the MESA stellar evolution code ...
Tim Hallatt, Sarah Millholland
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Astronomy & AstrophysicsThe formation and global spatial distribution of photochemically produced haze particles in exoplanet atmospheres remain key processes for understanding their observed properties. We aim to develop a flexible haze particle formation and evolution model suitable for time-dependent exoplanet atmosphere simulations.
Lee, Elspeth K. H. +4 more
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The Astrophysical JournalExoplanets with short orbit periods reside very close to their host stars. They transition very rapidly between different sectors of the circumstellar space environment along their orbit, leading to large variations of the magnetic field in the vicinity ...
Ofer Cohen +6 more
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Not All Sub-Neptune Exoplanets Have Magma Oceans
The Astrophysical Journal LettersThe evolution and structure of sub-Neptunes may be strongly influenced by interactions between the outer gaseous envelope of the planet and a surface magma ocean.
Bodie Breza +2 more
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The impact of stellar activity evolution on atmospheric mass loss of young exoplanets
The increasing number of known exoplanets raises questions about their demographics and the mechanisms that shape planets into how we observe them today. Young planets in close-in orbits are exposed to harsh environments due to the host star being magnetically highly active, which results in high X-ray and extreme UV fluxes impinging on the planet ...
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The Astronomical JournalAtmospheric mass loss is thought to induce the bimodality in the small planet population as we observe it today. Observationally, active mass loss can be traced by excess absorption in spectral lines of lighter species, such as the hydrogen Ly α line and
Ava Morrissey +8 more
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An Oxidation Gradient Straddling the Small Planet Radius Valley
The Astrophysical JournalWe present a population-level view of volatile gas species (H _2 , He, H _2 O, O _2 , CO, CO _2 , CH _4 ) distribution during the sub-Neptune to rocky planet transition, revealing in detail the dynamic nature of small planet atmospheric compositions. Our
Collin Cherubim +5 more
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The Orbital Imperative: Charting Cosmic Evolution from Gamma-Ray Bursts to Exoplanet Atmospheres
This paper explores the intricate connection between early universe energetic phenomena, specifically Gamma-Ray Bursts (GRBs), and the later-stage evolution of planetary systems, as evidenced by exoplanet atmospheres. We propose an "orbital imperative" framework, suggesting that gravitational dynamics and the resulting distribution of matter play a ...
Revista, Zen, ASTRO, 10
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