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Rapid growth of gas-giant cores by pebble accretion
The observed lifetimes of gaseous protoplanetary discs place strong constraints on gas and ice giant formation in the core accretion scenario. The approximately 10-Earth-mass solid core responsibleExpand
Rapid planetesimal formation in turbulent circumstellar disks
It is reported that boulders can undergo efficient gravitational collapse in locally overdense regions in the midplane of the disk, and it is found that gravitationally bound clusters form with masses comparable to dwarf planets and containing a distribution of boulder sizes. Expand
An abundance of small exoplanets around stars with a wide range of metallicities
Spectroscopic metallicities of the host stars of 226 small exoplanet candidates discovered by NASA's Kepler mission are reported, finding that planets with radii less than four Earth radii form around host stars with a wide range of metallicities (but on average a metallicity close to that of the Sun), whereas large planets preferentially form around stars with higher metallicities. Expand
Crashes at Critical Points
We study a rational expectation model of bubbles and crashes. The model has two components: (1) our key assumption is that a crash may be caused by local self-reinforcing imitation between noiseExpand
Forming the cores of giant planets from the radial pebble flux in protoplanetary discs
The formation of planetary cores must proceed rapidly in order for the giant planets to accrete their gaseous envelopes before the dissipation of the protoplanetary gas disc (less than or similar toExpand
Growth of asteroids, planetary embryos, and Kuiper belt objects by chondrule accretion
It is shown that the main growth of asteroids can result from gas drag–assisted accretion of chondrules, and planetesimal accretion and chondrule accretion play more equal roles in the formation of Moon-sized embryos in the terrestrial planet formation region. Expand
The PLATO 2.0 mission
PLATO 2.0 has recently been selected for ESA’s M3 launch opportunity (2022/24). Providing accurate key planet parameters (radius, mass, density and age) in statistical numbers, it addressesExpand
Separating gas-giant and ice-giant planets by halting pebble accretion
In the solar system giant planets come in two flavours: gas giants (Jupiter and Saturn) with massive gas envelopes, and ice giants (Uranus and Neptune) with much thinner envelopes around their cores.Expand
How to form planetesimals from mm-sized chondrules and chondrule aggregates
The size distribution of asteroids and Kuiper belt objects in the solar system is difficult to reconcile with a bottom-up formation scenario due to the observed scarcity of objects smaller thanExpand
Particle Clumping and Planetesimal Formation Depend Strongly on Metallicity
We present three-dimensional numerical simulations of particle clumping and planetesimal formation in protoplanetary disks with varying amounts of solid material. As centimeter-size pebbles settle toExpand