Letter reSeArCH
A gradual accretion of planetesimals along with the runaway gas accre-
tion may also produce a diluted core^15 ,^28. A relevant issue to be inves-
tigated elsewhere is whether the steep composition gradient needed
to preserve the diluted core can also be established after a series of
planetesimal-accretion events rather after than a single embryo’s giant
impact. Finally, extrasolar gas giant planets could also experience such
giant impacts, which may explain the extremely large bulk metallicities
of some giant exoplanets^29.
Online content
Any methods, additional references, Nature Research reporting summaries,
source data, extended data, supplementary information, acknowledgements, peer
review information; details of author contributions and competing interests; and
statements of data and code availability are available at https://doi.org/10.1038/
s41586-019-1470-2.
Received: 29 September 2018; Accepted: 20 June 2019;
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Publisher’s note: Springer Nature remains neutral with regard to jurisdictional
claims in published maps and institutional affiliations.© The Author(s), under exclusive licence to Springer Nature Limited 2019Density (g cm–3)10
–3
10
–1 101
10
–4
10
–2 1003,601.0 s 5,204.0 s6,803.0 s 8,403.0 s10,008.0 s 108,502.0 sabcdefFig. 3 | Two-dimensional snapshots of an off-centre collision between
the proto-Jupiter with a 10M⊕ rock/ice core and a 10M⊕ impactor.
a–f, Density contours in the orbital plane before the impact (a); during
disruption and accretion of the impactor (b–e); at about 30 h after the
impact (f). The time shown in each panel is measured since the start of the
simulation. See Methods for detailed discussion.
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