Related papers: Most Super-Earths Have Less Than 3% Water
The atmospheres of small exoplanets likely derive from a combination of geochemical outgassing and primordial gases left over from formation. Secondary atmospheres, such as those of Earth, Mars and Venus, are sourced by outgassing.…
Iron disproportionation reactions in mantle silicates can produce metallic iron that drives Earth's deep mantle toward metal saturation under reduced conditions. Subducting slabs transport hydrated silicates to these depths, where…
Recent discoveries of water-rich, sub-Neptunian to Neptunian-massed exoplanets with short-period orbits present a new parameter space for the study of exoplanetary dynamos. We explore the geometry of the dynamo source region within this…
The isotopic compositions of terrestrial hydrogen and nitrogen are clearly different from those of the nebular gas from which the solar system formed, and also differ from most of cometary values. Terrestrial N and H isotopic compositions…
Modeling the interior of exoplanets is essential to go further than the conclusions provided by mean density measurements. In addition to the still limited precision on the planets' fundamental parameters, models are limited by the…
It has been suggested that Earth's present water budget formed from oxidation reactions between its initial hydrogen-rich primordial atmosphere and its magma ocean. Here we examine this hypothesis by building a comprehensive…
A substantial number of super-Earths have been discovered, and atmospheres of transiting super-Earths have also been observed by transmission spectroscopy. Several lines of observational evidence indicate that most super-Earths do not…
The composition of the lower mantle $-$ comprising 56% of Earth's volume $-$ remains poorly constrained. Among the major elements, Mg/Si ratios ranging from $\sim$0.9$-$1.1, such as in rocky solar-system building blocks (or chondrites), to…
Internal redox reactions may irreversibly alter the mantle composition and volatile inventory of terrestrial and super-Earth exoplanets and affect the prospects for atmospheric observations. The global efficacy of these mechanisms, however,…
The nature of sub-Neptunes remains unknown due to degeneracies in interior structure solutions. However, a statistical set of small planets with measured masses and radii can be used to test the planet formation theory prediction of large…
Currently, there are about 3 dozen known super-Earth (M < 10 MEarth), of which 8 are transiting planets suitable for atmospheric follow-up observations. Some of the planets are exposed to extreme temperatures as they orbit close to their…
Terrestrial exoplanets in the canonical habitable zone may have a variety of initial water fractions due to random volatile delivery by planetesimals. If the total planetary water complement is high, the entire surface may be covered in…
The chemical composition of stars that have orbiting planets provides important clues about the frequency, architecture, and composition of exoplanet systems. We explore the possibility that stars from different galactic populations that…
Planets and stars are expected to be compositionally linked because they accrete from the same material reservoir. However, astronomical observations revealed the existence of exoplanets whose bulk density is far higher than what is…
The water content and habitability of terrestrial planets are determined during their final assembly, from perhaps a hundred 1000-km "planetary embryos" and a swarm of billions of 1-10 km "planetesimals." During this process, we assume that…
We generalize the problem of the semi-gray model to cases in which a non-negligible fraction of the stellar radiation falls on the long-wavelength range, and/or that the planetary long-wavelength emission penetrates into the transparent…
We study the transport of methane in the external water envelopes surrounding water-rich super-Earths and estimate its outgassing into the atmosphere. We investigate the influence of methane on the thermodynamics and mechanics of the water…
The climates of terrestrial planets with a small amount of water on their surface, called land planets, are significantly different from the climates of planets having a large amount of surface water. Land planets have a higher runaway…
A large fraction of giant planets have gaseous envelopes that are limited to about 10 % of their total mass budget. Such planets are present in the Solar System (Uranus, Neptune) and are frequently observed in short periods around other…
Differentiation in terrestrial planets is expected to include the formation of a metallic iron core. We predict the existence of terrestrial planets that have differentiated but have no metallic core--planets that are effectively a giant…