Results 111 to 120 of about 10,220 (206)

Blowin’ in the Nonisothermal Wind: Core-powered Mass Loss with Hydrodynamic Radiative Transfer

The Astrophysical Journal
The 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, Matthäus Schulik, Hilke E. Schlichting, James E. Owen   +3 more
doaj   +1 more source

Coupled Planetary Interior and Tidal Evolution

The Astrophysical Journal
We 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

Heating of the Atmospheres of Short-orbit Exoplanets by Their Rapid Orbital Motion through an Extreme Space Environment

The Astrophysical Journal
Exoplanets 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, Alex Glocer, Cecilia Garraffo, Julián D. Alvarado-Gómez, Jeremy J. Drake, Kristina Monsch, Farah Fauth Puigdomenech   +6 more
doaj   +1 more source

Modelling the effect of stellar metallicity on the XUV evolution of low-mass stars and its impact on exoplanet atmospheres/habitability

Monthly Notices of the Royal Astronomical Society
ABSTRACT Understanding how exoplanet atmospheres evolve is a key question in the context of habitability. One key process governing this evolution is atmospheric evaporation by stellar X-ray and EUV (extreme ultraviolet) emission (collectively, XUV).
Victor See, Charlotte Fairman, Louis Amard, Oliver Hall   +3 more
openaire   +2 more sources

Not All Sub-Neptune Exoplanets Have Magma Oceans

The Astrophysical Journal Letters
The 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, Matthew C. Nixon, Eliza M.-R. Kempton   +2 more
doaj   +1 more source

Searching for Helium Escape and a Low-density Atmosphere Around the 120 Myr Old Sub-Neptune HIP94235b Using CRIRES+

The Astronomical Journal
Atmospheric 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, George Zhou, Chelsea X. Huang, Duncan Wright, Neale Gibson, Keighley E. Rockcliffe, Elisabeth R. Newton, James Kirk, Daniel Bayliss   +8 more
doaj   +1 more source

An Oxidation Gradient Straddling the Small Planet Radius Valley

The Astrophysical Journal
We 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, Robin Wordsworth, Dan J. Bower, Paolo A. Sossi, Danica Adams, Renyu Hu   +5 more
doaj   +1 more source

A Large and Variable Leading Tail of Helium in a Hot Saturn Undergoing Runaway Inflation

The Astronomical Journal
Atmospheric escape shapes the fate of exoplanets, with statistical evidence for transformative mass loss imprinted across the mass–radius–insolation distribution.
Michael Gully-Santiago, Caroline V. Morley, Jessica Luna, Morgan MacLeod, Antonija Oklopčić, Aishwarya Ganesh, Quang H. Tran, Zhoujian Zhang, Brendan P. Bowler, William D. Cochran, Daniel M. Krolikowski, Suvrath Mahadevan, Joe P. Ninan, Guđmundur Stefánsson, Andrew Vanderburg, Joseph A. Zalesky, Gregory R. Zeimann   +16 more
doaj   +1 more source

Magma Ocean Interactions Can Explain JWST Observations of the Sub-Neptune TOI-270 d

The Astrophysical Journal
Sub-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, R. Sander Somers, Arjun B. Savel, Jegug Ih, Eliza M.-R. Kempton, Edward D. Young, Hilke E. Schlichting, Tim Lichtenberg, Luis Welbanks, William Misener, Anjali A. A. Piette, Nicholas F. Wogan   +11 more
doaj   +1 more source

Effects of Ultraviolet Radiation on Sub-Neptune Exoplanet Hazes through Laboratory Experiments

The Planetary Science Journal
Temperate 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, Sarah E. Moran, Neil Pearson, Tiffany Kataria, Chao He, Cara Pesciotta, Sarah M. Hörst, Pierre Haenecour, Travis Barman, Vishnu Reddy, Nikole K. Lewis, Véronique Vuitton   +11 more
doaj   +1 more source