Chris Ormel (University of Amsterdam) 27.04.2015

Abstract:
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Super-Earths are a new population of exoplanets. They are very common, orbit
their stars at close distances and, intriguingly, are often inferred to harbor a hydrogen/helium-rich atmosphere (a.k.a. mini-Neptunes). This implies that these planets assembled early, in the presence of a gas-rich circumstellar disks. However, most of the gas-rich super-Earth (occurrence: several tens of percent) did not turn into gas-dominant hot-Jupiters occurrence: less than 1%). I will explain that the properties of gas-rich super-Earths are hard to explain with traditional modeling of protoplanetary atmospheres, because these assume that the atmosphere is isolated and radially symmetric. Recent hydrodynamic simulations, however, offer new insights in how nature has avoided the "Jupiter-catastrophe".