相关论文: Extrasolar Carbon Planets
We develop a semi-analytic model for planet formation during the pre-main sequence contraction phase of a low mass star. During this evolution, the stellar magnetosphere maintains a fixed ratio between the inner disk radius and the stellar…
Much of a planet's composition could be determined right at the onset of formation. Laboratory experiments can constrain these early steps. This includes static tensile strength measurements or collisions carried out under Earth's gravity…
Kepler planets (including super-Earths and sub-Neptunes, from 1 to 4 Earth radii) are likely formed before the gaseous proto-planetary disks have dissipated, as are the Jovian planets. If the metal content in these disks resembles that in…
Recent discoveries of strongly misaligned transiting exoplanets pose a challenge to the established planet formation theory which assumes planetary systems to form and evolve in isolation. However, the fact that the majority of stars…
This paper reviews coagulation models for planet formation in the Kuiper Belt, emphasizing links to recent observations of our and other solar systems. At heliocentric distances of 35-50 AU, single annulus and multiannulus planetesimal…
The sample of known exoplanets is strongly biased to masses larger than the ones of the giant gaseous planets of the solar system. Recently, the discovery of two extrasolar planets of considerably lower masses around the nearby stars GJ 436…
Newly-formed planetary systems with ages of <10 Myr offer many unique insights into the formation, evolution, and fundamental properties of extrasolar planets. These planets have fallen beyond the limits of past surveys, but as we enter the…
The questions of how planets form and how common Earth-like planets are can be addressed by measuring the distribution of exoplanet masses and orbital periods. We report the occurrence rate of close-in planets (with orbital periods less…
The tidal heating of hypothetical rocky (or terrestrial) extra-solar planets spans a wide range of values depending on stellar masses and initial orbits. Tidal heating may be sufficiently large (in many cases, in excess of radiogenic…
The Capture Theory gives planet production through a tidal interaction between a condensed star and a diffuse protostar within a dense embedded cluster. Initial extensive and highly eccentric planetary orbits round-off and decay in a…
We hypothesise that planets are made by tidal downsizing of migrating giant planet embryos. The proposed scheme for planet formation consists of these steps: (i) a massive young protoplanetary disc fragments at R ~ several tens to hundreds…
The proportions of oxygen, carbon and major rock-forming elements (e.g. Mg, Fe, Si) determine a planet's dominant mineralogy. Variation in a planet's mineralogy subsequently affects planetary mantle dynamics as well as any deep water or…
We devise and exploit a data-driven, semi-empirical framework of galaxy formation and evolution, coupling it to recipes for planet formation from stellar and planetary science, to compute the cosmic planet formation rate, and the properties…
We present preliminary results from our spectroscopic search for planets within 1 AU of metal-poor field dwarfs using NASA time with HIRES on Keck I. The core accretion model of gas giant planet formation is sensitive to the metallicity of…
In an attempt to select stars that can host planets with characteristics similar to our own, we selected seven solar-type stars known to host planets in the habitable zone and for which spectroscopic stellar parameters are available. For…
Light and cold extrasolar planets such as OGLE 2005-BLG-390Lb, a 5.5 Earth-mass planet detected via microlensing, could be frequent in the Galaxy according to some preliminary results from microlensing experiments. These planets can be…
We describe a coagulation model that leads to the rapid formation of super-Earths and the cores of gas giant planets. Interaction of collision fragments with the gaseous disk is the crucial element of this model. The gas entrains small…
I suggest that in rare cases type Ia supernovae (SNe Ia) evaporate Jupiter-like planets that reside within a=50Ro from the SN, accounting for the presence of ~0.001Mo of hydrogen in the ejecta. It is not easy to form such planets. The…
Carbon is an essential element for a habitable world. Inner (r < 3 au) disk planetary carbon compositions are strongly influenced by supply and survival of carbonaceous solids. Here we trace the journey of carbon from the interstellar…
Super-Earths, objects slightly larger than Earth and slightly smaller than Uranus, have found a special place in exoplanetary science. As a new class of planetary bodies, these objects have challenged models of planet formation at both ends…