The standard model for giant planet formation is based on the accretion of solids by a growing planetary embryo, followed by rapid gas accretion once the planet exceeds a so-called critical mass1. However, the dominant size of the accreted solids (‘pebbles’ of the order of centimetres or ‘planetesimals’ of the order of kilometres to hundreds of kilometres) is unknown1,2. Recently, high-precision measurements of isotopes in meteorites have provided evidence for the existence of two reservoirs of small bodies in the early Solar System3. These reservoirs remained separated from ~1 Myr until ~3 Myr after the Solar System started to form. This separation is interpreted as resulting from Jupiter growing and becoming a barrier for material transport. In this framework, Jupiter reached ~20 Earth masses (M⊕) within ~1 Myr and slowly grew to ~50 M⊕ in the subsequent 2 Myr before reaching its present-day mass3. The evidence that Jupiter’s growth slowed after reaching 20 M⊕ for at least 2 Myr is puzzling because a planet of this mass is expected to trigger fast runaway gas accretion4,5. Here, we use theoretical models to describe the conditions allowing for such a slow accretion and show that Jupiter grew in three distinct phases. First, rapid pebble accretion supplied the major part of Jupiter’s core mass. Second, slow planetesimal accretion provided the energy required to hinder runaway gas accretion during the 2 Myr. Third, runaway gas accretion proceeded. Both pebbles and planetesimals therefore play an important role in Jupiter’s formation.
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Helled, R. et al. in Protostars and Planets VI (eds Beuther, H. et al.) 643–666 (Univ. Arizona Press, Tucson, AZ, 2014).
Johansen, A. et al. in Protostars and Planets VI (eds Beuther, H. et al.) 547–570 (Univ. Arizona Press, Tucson, AZ, 2014).
Kruijer, T. S., Burkhardt, C., Budde, G. & Kleine, T. Age of Jupiter inferred from the distinct genetics and formation times of meteorites. Proc. Natl Acad. Sci. USA 114, 6712–6716 (2017).
Pollack et al. Formation of the giant planets by concurrent accretion of solids and gas. Icarus 124, 62–85 (1996).
Alibert, Y., Mordasini, C., Benz, W. & Winisdoerffer, C. Models of giant planet formation with migration and disc evolution. Astron. Astrophys. 434, 343–353 (2005).
Trinquier, A., Birck, J. L. & Allègre, C. J. Widespread 54Cr heterogeneity in the inner Solar System. Astrophys. J. 655, 1179–1185 (2007).
Leya, I. et al. Titanium isotopes and the radial heterogeneity of the Solar System. Earth Planet. Sci. Lett. 266, 233–244 (2008).
Dauphas, N. & Schauble, E. A. Mass fractionation laws, mass-independent effects, and isotopic anomalies. Ann. Rev. Earth Planet. Sci. 44, 709–783 (2016).
Alibert, Y. et al. Theoretical models of planetary system formation: mass vs. semi-major axis. Astron. Astrophys. 558, A109 (2013).
Fortier, A., Alibert, Y., Carron, F., Benz, W. & Dittkrist, K.-M. Planet formation models: the interplay with the planetesimal disc. Astron. Astrophys. 549, A44 (2013).
Levison, H., Thommes, E. & Duncan, M. J. Modeling the formation of giant planet cores. I. Evaluating key processes. Astron. J. 139, 1297–1314 (2010).
Simon, J. B., Armitage, P. J., Youdin, A. N. & Li, R. Evidence for universality in the initial planetesimal mass function. Astrophys. J. Lett. 847, L12 (2017).
Morbidelli, A., Bottke, W. F., Nesvorný, D. & Levison, H. F. Asteroids were born big. Icarus 204, 558–573 (2009).
Kobayashi, H., Tanaka, H., Krivov, A. V. & Inaba, S. Planetary growth with collisional fragmentation and gas drag. Icarus 209, 836–847 (2010).
Bitsch, B., Lambrechts, M. & Johansen, A. The growth of planets by pebble accretion in evolving protoplanetary discs. Astron. Astrophys. 582, A112 (2015).
Bitsch, B., Lambrechts, M. & Johansen, A. The growth of planets by pebble accretion in evolving protoplanetary discs (corrigendum). Astron. Astrophys. 609, C2 (2018).
Ida, S. & Guillot, T. Formation of dust-rich planetesimals from sublimated pebbles inside of the snow line. Astron. Astrophys. 596, L3 (2016).
Hartmann, L., Calvet, N., Gullbring, E. & D’Alessio, P. Accretion and the evolution of T Tauri disks. Astrophys. J. 495, 385–400 (1998).
Zhou, J.-L. & Lin, D. N. C. Planetesimal accretion onto growing proto-gas giant planets. Astrophys. J. 666, 447–465 (2007).
Wahl, S. M. et al. Comparing Jupiter interior structure models to Juno gravity measurements and the role of a dilute core. Geophys. Res. Lett. 44, 4649–4659 (2017).
Mordasini, C., Alibert, Y. & Benz, W. Destruction of planetesimals in protoplanetary atmospheres. In Proc. Tenth Anniversary of 51 Peg-b: Status of and Prospects for Hot Jupiter Studies (eds Arnold, L. et al.) 84–86 (Frontier Group, 2006).
Lozovsky, M., Helled, R., Rosenberg, E. D. & Bodenheimer, P. Jupiter’s formation and its primordial internal structure. Astrophys. J. 836, 227 (2017).
Venturini, J. & Helled, R. The formation of mini-Neptunes. Astrophys. J. 848, 95 (2017).
Bollard, J. et al. Early formation of planetary building blocks inferred from Pb isotopic ages of chondrules. Sci. Adv. 3, e1700407 (2017).
Venturini, J., Alibert, Y. & Benz, W. Planet formation with envelope enrichment: new insights on planetary diversity. Astron. Astrophys. 596, A90 (2016).
Thiabaud, A. et al. From stellar nebula to planets: the refractory components. Astron. Astrophys. 562, A27 (2014).
Lissauer, J. J., Hubickyj, O., D’Angelo, G. & Bodenheimer, P. Models of Jupiter’s growth incorporating thermal and hydrodynamic constraints. Icarus 199, 338–350 (2009).
Saumon, D., Chabrier, G. & van Horn, H. M. An equation of state for low-mass stars and giant planets. Astrophys. J. Suppl. S. 99, 713–741 (1995).
Thompson, S. L. ANEOS—Analytic Equations of State for Shock Physics Codes—Input Manual Report SAND89-2951 (Sandia National Laboratories, 1990).
Ormel, C. W. An atmospheric structure equation for grain growth. Astrophys. J. Lett. 789, L18 (2014).
Mordasini, C. Grain opacity and the bulk composition of extrasolar planets. II. An analytical model for grain opacity in protoplanetary atmospheres. Astron. Astrophys. 572, A118 (2014).
Ormel, C. W., Shi, J.-M. & Kuiper, R. Hydrodynamics of embedded planets’ first atmospheres. II. A rapid recycling of atmospheric gas. Mon. Not. R. Astron. Soc. 447, 3512–3525 (2015).
Alibert, Y. The maximum mass of planetary embryos formed in core-accretion models. Astron. Astrophys. 606, 69–78 (2017).
Bitsch, B., Johansen, A., Lambrechts, M. & Morbidelli, A. The structure of protoplanetary discs around evolving young stars. Astron. Astrophys. 575, A28 (2015).
Ida, S. & Makino, J. Scattering of planetesimals by a protoplanet—slowing down of runaway growth. Icarus 106, 210–227 (1993).
Nakazawa, K., Ida, S. & Nakagawa, Y. Collisional probability of planetesimals revolving in the solar gravitational field. I. Basic formulation. Astron. Astrophys. 220, 293–300 (1989).
Inaba, S. et al. High-accuracy statistical simulation of planetary accretion. II. Comparison with N-body simulation. Icarus 149, 235–250 (2001).
Benz, W. & Asphaug, E. Catastrophic disruptions revisited. Icarus 142, 5–20 (1999).
Bell, K. R. & Lin, D. N. C. Using FU Orionis outbursts to constrain self-regulated protostellar disk models. Astrophys. J. 427, 987–1004 (1994).
Weidenschilling, S. J. The distribution of mass in the planetary system and solar nebula. Astrophys. Space Sci. 51, 153–158 (1977).
Drążkowska, J., Alibert, Y. & Moore, B. Close-in planetesimal formation by pile-up of drifting pebbles. Astron. Astrophys. 594, A105 (2016).
This work has been developed in the framework of the National Center for Competence in Research PlanetS funded by the Swiss National Science Foundation (SNSF). Y.A., W.B. and R.B. acknowledge support from the SNSF under grant 200020_172746. C.M. acknowledges support from the SNSF under grant BSSGI0_155816 ‘PlanetsInTime’. R.H. acknowledges support from SNSF project 200021_169054. Y.A. acknowledges the support of the European Research Council under grant 239605 ‘PLANETOGENESIS’. M.S. acknowledges the support of the European Research Council under the European Union’s Seventh Framework Programme (FP7/2007–2013)/ERC Grant agreement no. . We thank C. Surville for sharing the results of hydrodynamic simulations of disk–planet interaction before publication.
The authors declare no competing interests.
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Alibert, Y., Venturini, J., Helled, R. et al. The formation of Jupiter by hybrid pebble–planetesimal accretion. Nat Astron 2, 873–877 (2018). https://doi.org/10.1038/s41550-018-0557-2
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