Results 81 to 90 of about 581 (180)
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
doaj +1 more source
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 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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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 ...
openaire +2 more sources
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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A Large and Variable Leading Tail of Helium in a Hot Saturn Undergoing Runaway Inflation
The Astronomical JournalAtmospheric escape shapes the fate of exoplanets, with statistical evidence for transformative mass loss imprinted across the mass–radius–insolation distribution.
Michael Gully-Santiago +16 more
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Magma Ocean Interactions Can Explain JWST Observations of the Sub-Neptune TOI-270 d
The Astrophysical JournalSub-Neptunes with substantial atmospheres may possess magma oceans in contact with the overlying gas, with chemical interactions between the atmosphere and magma playing an important role in shaping atmospheric composition.
Matthew C. Nixon +11 more
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Effects of Ultraviolet Radiation on Sub-Neptune Exoplanet Hazes through Laboratory Experiments
The Planetary Science JournalTemperate sub-Neptune exoplanets could contain large inventories of water in various phases, such as water worlds with water-rich atmospheres or even oceans.
Lori Huseby +11 more
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The Solubility of N2 in High-pressure Ice and Its Consequent Outgassing Limitations in Water Worlds
The Astrophysical JournalExoplanets with a few percent water mass fraction may host a high-pressure ice layer that separates the atmosphere from the interior. We investigate the role played by this layer in the transport of N _2 between the interior and the atmosphere.
Amit Levi +3 more
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