Related papers: Experiments reveal extreme water generation during…
Diamonds melt at temperatures above 4000 K. There are no measurements of the steady-state rate of the reverse process: diamond nucleation from the melt, because experiments are difficult at these extreme temperatures and pressures. Using…
Using ab initio simulations we investigate whether water ice is stable in the cores of giant planets, or whether it dissolves into the layer of metallic hydrogen above. By Gibbs free energy calculations we find that for pressures between 10…
The atmosphere of a terrestrial planet that is replenished with secondary gases should have accumulated hydrogen-rich gas from its protoplanetary disk. Although a giant impact blows off a large fraction of the primordial atmosphere of a…
Recently there has been tremendous increase in the number of identified extra-solar planetary systems. Our understanding of their formation is tied to exoplanet internal structure models, which rely upon equations of state of light elements…
Exoplanet surveys around M dwarfs have detected a growing number of exoplanets with Earth-like insolation. It is expected that some of those planets are rocky planets with the potential for temperate climates favourable to surface liquid…
[Abridged] We present the first results of hydrodynamical simulations that follow the formation of galaxies to z=0 in spherical regions of radius ~20 Mpc/h drawn from the Millennium Simulation. The regions have overdensities that deviate by…
In this thesis we have identified two star formation sites for star formation in galaxies which differ widely in metal content. We conclude that `massive' star formation that occurs in a high density, high metallicity environment, like that…
Astronomers have discovered a handful of exoplanets with rocky bulk compositions but orbiting so close to their host star that the surface of the planet must be at least partially molten. It is expected that the dayside of such "lava…
Because of the high energies involved, giant impacts that occur during planetary accretion cause large degrees of melting. The depth of melting in the target body after each collision determines the pressure and temperature conditions of…
This is the second paper in a series where we build a self-consistent model to simulate the mass-loss process of a close-orbit magnetized giant exoplanet, so-called hot Jupiter (HJ). In this paper we generalize the hydrodynamic (HD) model…
Small planets ($\sim$1--3.9 $\Rearth$) constitute more than half of the inventory of the 4000-plus exoplanets discovered so far. Smaller planets are sufficiently dense to be rocky, but those with radii larger than $\sim$1.6 $\Rearth$ are…
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…
Most current models of hot-exoplanet atmospheres assume shallow heating, a strong day-night differential heating near the top of the atmosphere. Here we investigate the effects of energy deposition at differing depths in a model tidally…
We show that planet formation via both gravitational collapse and core accretion is unlikely to occur in equal mass binary systems with moderate (~ 50 AU) semi-major axes. Internal thermal energy generation in the disks is sufficient to…
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 elemental compositions of exoplanets encode information about their formation environments and internal structures. While volatile ratios such as carbon-to-oxygen (C/O) are used to trace formation location, the rock-forming elements -…
Disk instability is an attractive yet controversial means for the rapid formation of giant planets in our solar system and elsewhere. Recent concerns regarding the first adiabatic exponent of molecular hydrogen gas are addressed and shown…
Recent spacecraft observations exploring solar system properties impact standard paradigms of the formation of stars, planets and comets. We stress the unexpected cloud of microscopic dust resulting from the DEEP IMPACT mission, and the…
Theoretical models predict the condensation of silicon carbide around host stars with C/O ratios higher than 0.65 (cf. C/O$_{\mathrm{Sun}}$ = 0.54), in addition to its observations in meteorites, interstellar medium and protoplanetary…
The delivery of water to the inner Solar System rocky planets, including Earth, remains debated, as standard models assume that they formed from dry grains, inside the snowline of the protosolar nebula. However, a recent work showed that a…