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تسجيل مستخدم جديدForming Jupiter, Saturn, Uranus and Neptune in Few Million Years by Core Accretion
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Giant planet formation process is still not completely understood. The current most accepted paradigm, the core instability model, explains several observed properties of the solar systems giant planets but, to date, has faced difficulties to account for a formation time shorter than the observational estimates of protoplanetary disks lifetimes, especially for the cases of Uranus and Neptune. In the context of this model, and considering a recently proposed primordial solar system orbital structure, we performed numerical calculations of giant planet formation. Our results show that if accreted planetesimals follow a size distribution in which most of the mass lies in 30-100 meter sized bodies, Jupiter, Saturn, Uranus and Neptune may have formed according to the nucleated instability scenario. The formation of each planet occurs within the time constraints and they end up with core masses in good agreement with present estimations.
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The origin of Uranus and Neptune remains a challenge for planet formation models. A potential explanation is that the planets formed from a population of a few planetary embryos with masses of a few Earth masses which formed beyond Saturns orbit and
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We present two new in situ core accretion simulations of Saturn with planet formation timescales of 3.37 Myr (model S0) and 3.48 Myr (model S1), consistent with observed protostellar disk lifetimes. In model S0, we assume rapid grain settling reduces
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