Results 21 to 30 of about 700 (166)

Sub-Neptunes Are Drier than They Seem: Rethinking the Origins of Water-rich Worlds

The Astrophysical Journal Letters
Recent claims of biosignature gases in sub-Neptune atmospheres have renewed interest in water-rich sub-Neptunes with surface oceans, often referred to as Hycean planets. These planets are hypothesized to form beyond the snow line, accreting large amounts
Aaron Werlen, Caroline Dorn, Remo Burn, Hilke E. Schlichting, Simon L. Grimm, Edward D. Young   +5 more
doaj   +1 more source

The Effects of Non-ideal Mixing in Planetary Magma Oceans and Atmospheres

The Astrophysical Journal
Sub-Neptunes with hydrogen-rich envelopes are expected to sustain long-lived magma oceans that continuously exchange volatiles with their overlying atmospheres.
Aaron Werlen, Edward D. Young, Hilke E. Schlichting, Caroline Dorn, Anat Shahar   +4 more
doaj   +1 more source

A Possible Metal-dominated Atmosphere below the Thick Aerosols of GJ 1214 b Suggested by Its JWST Panchromatic Transmission Spectrum

The Astrophysical Journal Letters
GJ 1214b is the archetype sub-Neptune for which thick aerosols have prevented us from constraining its atmospheric properties for over a decade. In this study, we leverage the panchromatic transmission spectrum of GJ 1214b established by the Hubble Space
Kazumasa Ohno, Everett Schlawin, Taylor J. Bell, Matthew M. Murphy, Thomas G. Beatty, Luis Welbanks, Thomas P. Greene, Jonathan J. Fortney, Vivien Parmentier, Isaac R. Edelman, Nishil Mehta, Marcia J. Rieke   +11 more
doaj   +1 more source

Thermoelastic Contraction as a Suppressor of Atmospheric Escape in Close-in Exoplanets

The Astrophysical Journal
The survival of volatile-rich atmospheres on close-in exoplanets challenges classical escape models. We identify a fully classical, interior-driven correction: thermoelastic contraction of the planetary mantle slightly increases the gravitational binding
L. Yıldız, D. Kaykı, E. Güdekli
doaj   +1 more source

Oxidation of the Interiors of Carbide Exoplanets

The Planetary Science Journal, 2020
Astrophysical measurements have shown that some stars have sufficiently high carbon-to-oxygen ratios such that the planets they host would be mainly composed of carbides instead of silicates.
H. W. Horn, E. Garhart, K. Leinenweber, V. Prakapenka, E. Greenberg, S.-H. Shim   +5 more
doaj   +1 more source

Soot Planets Instead of Water Worlds

The Astrophysical Journal Letters
Some low-density exoplanets are thought to be water-rich worlds that formed beyond the snow line of their protoplanetary disk, possibly accreting coequal portions of rock and water.
Jie Li, Edwin A. Bergin, Marc M. Hirschmann, Geoffrey A. Blake, Fred J. Ciesla, Eliza M.-R. Kempton   +5 more
doaj   +1 more source

Ohmic Dissipation During the Formation of Super-Earth

The Astrophysical Journal, 2023
The super-Earth population, as one of the representatives of exoplanets, plays an important role in constraining the planet formation theories. According to the prediction from core-accretion models, super-Earths should be rare because their masses are ...
Shi Jia, Wei, Zhong, Cong Yu
doaj   +1 more source

Impacting Atmospheres: How Late-stage Pollution Alters Exoplanet Composition

The Astrophysical Journal
The atmospheric composition of exoplanets is often considered as a probe of the planet’s formation conditions. How exactly the initial chemical memory may be altered from the birth to the final state of the planet, however, remains unknown.
Emilia Vlahos, Yayaati Chachan, Vincent Savignac, Eve J. Lee   +3 more
doaj   +1 more source

Enhanced constraints on the interior composition and structure of terrestrial exoplanets [PDF]

Monthly Notices of the Royal Astronomical Society, 2018
Exoplanet interior modelling usually makes the assumption that the elemental abundances of a planet are identical to those of its host star. Host stellar abundances are good proxies of planetary abundances, but only for refractory elements. This is particularly true for terrestrial planets, as evidenced by the relative differences in bulk chemical ...
H S Wang, F Liu, T R Ireland, R Brasser, D Yong, C H Lineweaver   +5 more
openaire   +3 more sources

The Not-so Dramatic Effect of Advective Flows on Gas Accretion

The Astrophysical Journal
Super-Earths and mini-Neptunes are the most common types of exoplanets discovered, yet the physics of their formation are still debated. Standard core accretion models in gas-rich environments find that typical mini-Neptune mass planets would blow up ...
Vincent Savignac, Eve J. Lee
doaj   +1 more source