2010/07/23 by Sergei Nayakshin · 3 citations
Physics and Astronomy · #Astro and Planetary Science #Astrophysics and Star Formation Studies #Atmosphere (unit) #Gas giant #Giant planet #Gravitation #Gravitational collapse #Mantle (geology) #Planet #Stellar, planetary, and galactic studies #Terrestrial planet #astro-ph.EP #astro-ph.SR
paper · pdf · doi:10.1111/j.1365-2966.2011.18230.x
20 pages, submitted to MNRAS, referred to as "paper II" in series
arxiv created 2010/07/23 · openalex publication_date 2011/03/09 · arxiv updated 2015/05/19 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
Giant planet embryos are believed to be spawned by gravitational instability in massive extended (R∼ 100 au) protostellar discs. In a recent paper, we have shown that dust can sediment inside the embryos, as argued earlier by Boss in a slightly different model. Here we study numerically the next stage of this process – the formation of a solid core. If conditions are conducive to solid core formation, the centre of the gas cloud goes through the following sequence of phases: (i) becomes grain (and metal) rich; (ii) forms a terrestrial mass solid core via a rapid collapse driven by self-gravity of the grains; (iii) starts to accrete a gaseous atmosphere when the solid core reaches mass of a few to 10 M⊕. This sequence of events may build either terrestrial planet cores or metal-rich giant planets inside the larger gas reservoir of the giant planet embryo. In a companion letter we argue that tidal and irradiation effects from the parent star should disrupt the outer metal-poor layers of the embryo, releasing nearly ‘ready to use’ planets. We propose this as an alternative way to build planets.