Astronomical observations reveal that protoplanetary disks around young stars commonly have ring- and gap-like structures in their dust distributions. These features are associated with pressure bumps trapping dust particles at specific locations, which simulations show are ideal sites for planetesimal formation. Here we show that our Solar System may have formed from rings of planetesimals—created by pressure bumps—rather than a continuous disk. We model the gaseous disk phase assuming the existence of pressure bumps near the silicate sublimation line (at T ~ 1,400 K), water snowline (at T ~ 170 K) and CO snowline (at T ~ 30 K). Our simulations show that dust piles up at the bumps and forms up to three rings of planetesimals: a narrow ring near 1 au, a wide ring between ~3–4 au and ~10–20 au and a distant ring between ~20 au and ~45 au. We use a series of simulations to follow the evolution of the innermost ring and show how it can explain the orbital structure of the inner Solar System and provides a framework to explain the origins of isotopic signatures of Earth, Mars and different classes of meteorites. The central ring contains enough mass to explain the rapid growth of the giant planets’ cores. The outermost ring is consistent with dynamical models of Solar System evolution proposing that the early Solar System had a primordial planetesimal disk beyond the current orbit of Uranus.
This is a preview of subscription content, access via your institution
Subscribe to Nature+
Get immediate online access to Nature and 55 other Nature journal
Subscribe to Journal
Get full journal access for 1 year
only $9.92 per issue
All prices are NET prices.
VAT will be added later in the checkout.
Tax calculation will be finalised during checkout.
Get time limited or full article access on ReadCube.
All prices are NET prices.
Simulation data that support the findings of this study or were used to make the plots are available from the corresponding author upon reasonable request. Source data associated with the main figures of the manuscript are available at https://andreizidoro.com/simulation-data.
Dust evolution simulations were performed using a modified version of the code Two-pop-py5, publicly available at https://github.com/birnstiel/two-pop-py, with modifications described in ref. 20. N-body simulations modelling the growth of planetesimals to planetary embryos were performed using LIPAD93. This is a proprietary software product funded by the Southwest Research Institute that is not publicly available. It is based on the N-body integrator SyMBA, which is publicly available at https://www.boulder.swri.edu/swifter/. Simulations of the late stage of accretion of terrestrial planets were performed using the Mercury N-body integrator94, publicly available at https://github.com/4xxi/mercury.
DeMeo, F. E. & Carry, B. Solar System evolution from compositional mapping of the asteroid belt. Nature 505, 629–634 (2014).
Kruijer, T. S., Kleine, T. & Borg, L. E. The great isotopic dichotomy of the early Solar System. Nat. Astron. 4, 32–40 (2020).
Grewal, D. S., Dasgupta, R. & Marty, B. A very early origin of isotopically distinct nitrogen in inner Solar System protoplanets. Nat. Astron. 5, 356–364 (2021).
Brasser, R. & Mojzsis, S. J. The partitioning of the inner and outer Solar System by a structured protoplanetary disk. Nat. Astron. 4, 492–499 (2020).
Birnstiel, T., Klahr, H. & Ercolano, B. A simple model for the evolution of the dust population in protoplanetary disks. Astron. Astrophys. 539, A148 (2012).
Walsh, K. J., Morbidelli, A., Raymond, S. N., O’Brien, D. P. & Mandell, A. M. A low mass for Mars from Jupiter’s early gas-driven migration. Nature 475, 206–209 (2011).
Raymond, S. N. & Izidoro, A. Origin of water in the inner Solar System: planetesimals scattered inward during Jupiter and Saturn’s rapid gas accretion. Icarus 297, 134–148 (2017).
Huang, J. et al. The Disk Substructures at High Angular Resolution Project (DSHARP). II. Characteristics of annular substructures. Astrophys. J. Lett. 869, L42 (2018).
Dullemond, C. P. et al. The Disk Substructures at High Angular Resolution Project (DSHARP). VI. Dust trapping in thin-ringed protoplanetary disks. Astrophys. J. Lett. 869, L46 (2018).
Johansen, A. et al. Rapid planetesimal formation in turbulent circumstellar disks. Nature 448, 1022–1025 (2007).
Müller, J., Savvidou, S. & Bitsch, B. The water-ice line as a birthplace of planets: implications of a species-dependent dust fragmentation threshold. Astron. Astrophys. 650, A185 (2021).
Charnoz, S., Avice, G., Hyodo, R., Pignatale, F. C. & Chaussidon, M. Forming pressure traps at the snow line to isolate isotopic reservoirs in the absence of a planet. Astron. Astrophys. 652, A35 (2021).
Gundlach, B. & Blum, J. The stickiness of micrometer-sized water-ice particles. Astrophys. J. 798, 34 (2015).
Desch, S. J. & Turner, N. J. High-temperature ionization in protoplanetary disks. Astrophys. J. 811, 156 (2015).
Flock, M., Fromang, S., Turner, N. J. & Benisty, M. 3D radiation nonideal magnetohydrodynamical simulations of the inner rim in protoplanetary disks. Astrophys. J. 835, 230 (2017).
Qi, C. et al. Imaging of the CO snow line in a solar nebula analog. Science 341, 630–632 (2013).
van ’t Hoff, M. L. R., Walsh, C., Kama, M., Facchini, S. & van Dishoeck, E. F. Robustness of N2H+ as tracer of the CO snowline. Astron. Astrophys. 599, A101 (2017).
Pinilla, P. et al. Trapping dust particles in the outer regions of protoplanetary disks. Astron. Astrophys. 538, A114 (2012).
Dittrich, K., Klahr, H. & Johansen, A. Gravoturbulent planetesimal formation: the positive effect of long-lived zonal flows. Astrophys. J. 763, 117 (2013).
Izidoro, A., Bitsch, B. & Dasgupta, R. The effect of a strong pressure bump in the Sun’s natal disk: terrestrial planet formation via planetesimal accretion rather than pebble accretion. Astrophys. J. 915, 62 (2021).
Dra̧żkowska, J. & Alibert, Y. Planetesimal formation starts at the snow line. Astron. Astrophys. 608, A92 (2017).
Simon, J. B., Armitage, P. J., Li, R. & Youdin, A. N. The mass and size distribution of planetesimals formed by the streaming instability. I. The role of self-gravity. Astrophys. J. 822, 55 (2016).
Chambers, J. A semi-analytic model for oligarchic growth. Icarus 180, 496–513 (2006).
Tanaka, H., Takeuchi, T. & Ward, W. R. Three-dimensional interaction between a planet and an isothermal gaseous disk. I. Corotation and Lindblad torques and planet migration. Astrophys. J. 565, 1257–1274 (2002).
Lambrechts, M. et al. Formation of planetary systems by pebble accretion and migration. How the radial pebble flux determines a terrestrial-planet or super-Earth growth mode. Astron. Astrophys. 627, A83 (2019).
Hansen, B. M. S. Formation of the terrestrial planets from a narrow annulus. Astrophys. J. 703, 1131–1140 (2009).
Izidoro, A., Haghighipour, N., Winter, O. ~C. & Tsuchida, M. Terrestrial planet formation in a protoplanetary disk with a local mass depletion: a successful scenario for the formation of Mars. Astrophys. J. 782, 31 (2014).
Izidoro, A., Raymond, S. N., Morbidelli, A. & Winter, O. C. Terrestrial planet formation constrained by Mars and the structure of the asteroid belt. Mon. Not. R. Astron. Soc. 453, 3619–3634 (2015).
Levison, H. F., Kretke, K. A. & Duncan, M. J. Growing the gas-giant planets by the gradual accumulation of pebbles. Nature 524, 322–324 (2015).
Raymond, S. N. & Izidoro, A. The empty primordial asteroid belt. Sci. Adv. 3, e1701138 (2017).
Morbidelli, A. et al. Fossilized condensation lines in the Solar System protoplanetary disk. Icarus 267, 368–376 (2016).
Warren, P. H. Stable-isotopic anomalies and the accretionary assemblage of the Earth and Mars: a subordinate role for carbonaceous chondrites. Earth Planet. Sci. Lett. 311, 93–100 (2011).
Dauphas, N. et al. Calcium-48 isotopic anomalies in bulk chondrites and achondrites: evidence for a uniform isotopic reservoir in the inner protoplanetary disk. Earth Planet. Sci. Lett. 407, 96–108 (2014).
Wittmann, A. et al. Petrography and composition of Martian regolith breccia meteorite Northwest Africa 7475. Meteorit. Planet. Sci. 50, 326–352 (2015).
Lodders, K. An oxygen isotope mixing model for the accretion and composition of rocky planets. Space Sci. Rev. 92, 341–354 (2000).
Dauphas, N. The isotopic nature of the Earth’s accreting material through time. Nature 541, 521–524 (2017).
Brasser, R., Mojzsis, S. J., Matsumura, S. & Ida, S. The cool and distant formation of Mars. Earth Planet. Sci. Lett. 468, 85–93 (2017).
Bottke, W. F., Nesvorný, D., Grimm, R. E., Morbidelli, A. & O’Brien, D. P. Iron meteorites as remnants of planetesimals formed in the terrestrial planet region. Nature 439, 821–824 (2006).
Chambers, J. E. Making more terrestrial planets. Icarus 152, 205–224 (2001).
Kokubo, E. & Ida, S. Formation of protoplanet systems and diversity of planetary systems. Astrophys. J. 581, 666–680 (2002).
Bus, S. J. & Binzel, R. P. Phase II of the Small Main-Belt Asteroid Spectroscopic Survey. A feature-based taxonomy. Icarus 158, 146–177 (2002).
Urey, H. C. The cosmic abundances of potassium, uranium, and thorium and the heat balances of the Earth, the Moon, and Mars. Proc. Natl Acad. Sci. USA 41, 127–144 (1955).
Vernazza, P., Zanda, B., Nakamura, T., Scott, E. R. D. & Russell, S. In The Formation and Evolution of Ordinary Chondrite Parent Bodies (eds Bottke, W. F., DeMeo, F. E. & Michel, P.) 617–634 (University of Arizona Press, 2015).
Weiss, B. P. & Elkins-Tanton, L. T. Differentiated planetesimals and the parent bodies of chondrites. Annu. Rev. Earth Planet. Sci. 41, 529–560 (2013).
Neumann, W., Kruijer, T. S., Breuer, D. & Kleine, T. Multistage core formation in planetesimals revealed by numerical modeling and Hf–W chronometry of iron meteorites. J. Geophys. Res. Planets 123, 421–444 (2018).
Sanders, I. S. & Scott, E. R. D. The origin of chondrules and chondrites: debris from low-velocity impacts between molten planetesimals? Meteorit. Planet. Sci. 47, 2170–2192 (2012).
Moskovitz, N. & Gaidos, E. Differentiation of planetesimals and the thermal consequences of melt migration. Meteorit. Planet. Sci. 46, 903–918 (2011).
Asphaug, E., Jutzi, M. & Movshovitz, N. Chondrule formation during planetesimal accretion. Earth Planet. Sci. Lett. 308, 369–379 (2011).
Desch, S. J. & Connolly, J. H. C. A model of the thermal processing of particles in solar nebula shocks: application to the cooling rates of chondrules. Meteorit. Planet. Sci. 37, 183–207 (2002).
Yang, C. C., Johansen, A. & Carrera, D. Concentrating small particles in protoplanetary disks through the streaming instability. Astron. Astrophys. 606, A80 (2017).
Kunitomo, M., Guillot, T., Ida, S. & Takeuchi, T. Revisiting the pre-main-sequence evolution of stars. II. Consequences of planet formation on stellar surface composition. Astron. Astrophys. 618, A132 (2018).
Izidoro, A., Morbidelli, A., Raymond, S. N., Hersant, F. & Pierens, A. Accretion of Uranus and Neptune from inward-migrating planetary embryos blocked by Jupiter and Saturn. Astron. Astrophys. 582, A99 (2015).
Tsiganis, K., Gomes, R., Morbidelli, A. & Levison, H. F. Origin of the orbital architecture of the giant planets of the Solar System. Nature 435, 459–461 (2005).
Nesvorný, D. Dynamical evolution of the early Solar System. Annu. Rev. Astron. Astrophys. 56, 137–174 (2018).
Deienno, R., Morbidelli, A., Gomes, R. S. & Nesvorný, D. Constraining the giant planets’ initial configuration from their evolution: implications for the timing of the planetary instability. Astron. J. 153, 153 (2017).
Nesvorný, D. et al. OSSOS XX: the meaning of Kuiper Belt colors. Astron. J. 160, 46 (2020).
Gladman, B., Marsden, B. G. & Vanlaerhoven, C. In The Solar System Beyond Neptune (eds Barucci, M. A., Boehnhardt, H., Cruikshank, D. P. & Morbidelli, A.) 43–57 (University of Arizona Press, 2008).
Fressin, F. et al. The false positive rate of Kepler and the occurrence of planets. Astrophys. J. 766, 81 (2013).
Mayor, M. et al. The HARPS search for southern extra-solar planets XXXIV. Occurrence, mass distribution and orbital properties of super-Earths and Neptune-mass planets. Preprint at https://arxiv.org/abs/1109.2497 (2011).
Izidoro, A. et al. Formation of planetary systems by pebble accretion and migration. Hot super-Earth systems from breaking compact resonant chains. Astron. Astrophys. 650, A152 (2021).
Morbidelli, A. Planet formation by pebble accretion in ringed disks. Astron. Astrophys. 638, A1 (2020).
Lambrechts, M., Johansen, A. & Morbidelli, A. Separating gas-giant and ice-giant planets by halting pebble accretion. Astron. Astrophys. 572, A35 (2014).
Raymond, S. N., Izidoro, A. & Morbidelli, A. In Solar System Formation in the Context of Extra-Solar Planets inPlanetary Astrobiology (eds Meadows, V. S., Arney, G. N., Schmidt, B. E. & Des Marais, D. J.) (University of Arizona Press, 2020).
Pinilla, P., Pohl, A., Stammler, S. M. & Birnstiel, T. Dust density distribution and imaging analysis of different ice lines in protoplanetary disks. Astrophys. J. 845, 68 (2017).
Dra̧żkowska, J. & Dullemond, C. P. Planetesimal formation during protoplanetary disk buildup. Astron. Astrophys. 614, A62 (2018).
Ueda, T., Flock, M. & Okuzumi, S. Dust pileup at the dead-zone inner edge and implications for the disk shadow. Astrophys. J. 871, 10 (2019).
Ida, S., Guillot, T. & Morbidelli, A. The radial dependence of pebble accretion rates: a source of diversity in planetary systems. I. Analytical formulation. Astron. Astrophys. 591, A72 (2016).
Zhang, Y. & Jin, L. The evolution of the snow line in a protoplanetary disk. Astrophys. J. 802, 58 (2015).
Zhang, K., Blake, G. A. & Bergin, E. A. Evidence of fast pebble growth near condensation fronts in the HL Tau protoplanetary disk. Astrophys. J. Lett. 806, L7 (2015).
Baillié, K., Marques, J. & Piau, L. Building protoplanetary disks from the molecular cloud: redefining the disk timeline. Astron. Astrophys. 624, A93 (2019).
Bitsch, B., Morbidelli, A., Lega, E. & Crida, A. Stellar irradiated discs and implications on migration of embedded planets. II. Accreting-discs. Astron. Astrophys. 564, A135 (2014).
Ziampras, A., Ataiee, S., Kley, W., Dullemond, C. P. & Baruteau, C. The impact of planet wakes on the location and shape of the water ice line in a protoplanetary disk. Astron. Astrophys. 633, A29 (2020).
Birnstiel, T., Andrews, S. M., Pinilla, P. & Kama, M. Dust evolution can produce scattered light gaps in protoplanetary disks. Astrophys. J. Lett. 813, L14 (2015).
Drążkowska, J., Alibert, Y. & Moore, B. Close-in planetesimal formation by pile-up of drifting pebbles. Astron. Astrophys. 594, A105 (2016).
Asplund, M., Grevesse, N., Sauval, A. J. & Scott, P. The chemical composition of the Sun. Annu. Rev. Astron. Astrophys. 47, 481–522 (2009).
Desch, S. J., Kalyaan, A. & O’D. Alexander, C. M. The effect of Jupiter’s formation on the distribution of refractory elements and inclusions in meteorites. Astrophys. J. Suppl. Ser. 238, 11 (2018).
Pinilla, P., Lenz, C. T. & Stammler, S. M. Growing and trapping pebbles with fragile collisions of particles in protoplanetary disks. Astron. Astrophys. 645, A70 (2021).
Schneider, A. D. & Bitsch, B. How drifting and evaporating pebbles shape giant planets. I. Heavy element content and atmospheric C/O. Astron. Astrophys. 654, A71 (2021).
Lenz, C. T., Klahr, H., Birnstiel, T., Kretke, K. & Stammler, S. Constraining the parameter space for the solar nebula. The effect of disk properties on planetesimal formation. Astron. Astrophys. 640, A61 (2020).
Lenz, C. T., Klahr, H. & Birnstiel, T. Planetesimal population synthesis: pebble flux-regulated planetesimal formation. Astrophys. J. 874, 36 (2019).
Okuzumi, S. & Hirose, S. Planetesimal formation in magnetorotationally dead zones: critical dependence on the net vertical magnetic flux. Astrophys. J. Lett. 753, L8 (2012).
Lynden-Bell, D. & Pringle, J. E. The evolution of viscous discs and the origin of the nebular variables. Mon. Not. R. Astron. Soc. 168, 603–637 (1974).
Shakura, N. I. & Sunyaev, R. A. Black holes in binary systems. Observational appearance. Astron. Astrophys. 24, 337–355 (1973).
Bai, X.-N. & Stone, J. M. Magnetic flux concentration and zonal flows in magnetorotational instability turbulence. Astrophys. J. 796, 31 (2014).
Gerbig, K., Lenz, C. T. & Klahr, H. Linking planetesimal and dust content in protoplanetary disks via a local toy model. Astron. Astrophys. 629, A116 (2019).
Ormel, C. W. & Klahr, H. H. The effect of gas drag on the growth of protoplanets. Analytical expressions for the accretion of small bodies in laminar disks. Astron. Astrophys. 520, A43 (2010).
Johansen, A. & Lambrechts, M. Forming planets via pebble accretion. Annu. Rev. Earth Planet. Sci. 45, 359–387 (2017).
Walsh, K. J. & Levison, H. F. Planetesimals to terrestrial planets: collisional evolution amidst a dissipating gas disk. Icarus 329, 88–100 (2019).
Deienno, R., Walsh, K. J., Kretke, K. A. & Levison, H. F. Energy dissipation in large collisions—no change in planet formation outcomes. Astrophys. J. 876, 103 (2019).
Morbidelli, A. & Crida, A. The dynamics of Jupiter and Saturn in the gaseous protoplanetary disk. Icarus 191, 158–171 (2007).
Raymond, S. N., Quinn, T. & Lunine, J. I. Making other earths: dynamical simulations of terrestrial planet formation and water delivery. Icarus 168, 1–17 (2004).
O’Brien, D. P., Morbidelli, A. & Levison, H. F. Terrestrial planet formation with strong dynamical friction. Icarus 184, 39–58 (2006).
Levison, H. F., Duncan, M. J. & Thommes, E. A Lagrangian Integrator for Planetary Accretion and Dynamics (LIPAD). Astron. J. 144, 119 (2012).
Chambers, J. E. A hybrid symplectic integrator that permits close encounters between massive bodies. Mon. Not. R. Astron. Soc. 304, 793–799 (1999).
A. Izidoro, R. Dasgupta and A. Isella acknowledge NASA grant 80NSSC18K0828 for financial support during preparation and submission of the work. A. Isella and A. Izidoro acknowledge support from the Welch Foundation grant No. C-2035-20200401. B.B. thanks the European Research Council (ERC Starting Grant 757448-PAMDORA) for financial support. R. Deienno acknowledges support from the NASA Emerging Worlds program, grant 80NSSC21K0387. S.N.R. thanks the CNRS’s PNP programme for support. A. Izidoro thanks M. Maurice for numerous inspirational discussions, and the Brazilian Federal Agency for Support and Evaluation of Graduate Education (CAPES), in the scope of the Programme CAPES-PrInt, process number 88887.310463/2018-00, International Cooperation Project number 3266.
The authors declare no competing interests.
Peer review information Nature Astronomy thanks Eiichiro Kokubo and Bradley Hansen for their contribution to the peer review of this work.
Publisher’s note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
a) Including the effects of planetesimal formation via zonal flows80, see Eq. (8). b) Neglecting the effects of planetesimal formation via zonal flows21,65. Final distribution of planetesimals in a simulation with three pressure bumps. Top and middle panels show the evolution of the gas and pebble surface densities, respectively. The initial dust-to-gas ratio is Z0 = 1.3%, ϵ = 1 × 10−4, αt = αν/27. The final rings contain 2.5 M⊕ (inner), 85 M⊕ (central), and 18 M⊕ (outer) in planetesimals. In both simulations rc = 25 au.
Extended Data Fig. 2 Final distribution of planetesimals in a simulation with two pressure bumps (β = 0.7).
Final distribution of planetesimals in a simulation with two pressure bumps (β = 0.7). Top and middle panels show the evolution of the gas and pebble surface densities, respectively. The planetesimal formation efficiency in this simulation is ϵ = 7.5 × 10−7. The initial dust-to-gas ratio is Z0 = 0.01, αt = αν/40, αMRI = 3αν, and rc = ∞.
Extended Data Fig. 3 Cumulative mass fraction distributions representing the feeding zones of terrestrial planets in simulations with Jupiter and Saturn in their current orbits.
a) Inner planetesimal ring with surface density profile given by Σpla ∝ r−1. Curves are computed from 6 solar system analogues. b) Inner planetesimal ring with surface density profile given by Σpla ∝ r−5.5. Curves are computed from 12 solar system analogues. Cumulative mass fraction distributions representing the feeding zones of terrestrial planets in simulations with Jupiter and Saturn in their current orbits. Thin green, blue and red curves represent Venus, Earth, and Mars analogues. Shaded regions encompassing each thin line represent 95% confidence bands derived from the Kolmogorov–Smirnov statistic. Each selected planetary system contains one single Venus, Earth, and Mars-analogue.
Extended Data Fig. 4 Simulation using the same parameters of simulation shown in Extended Data Figure 2, but considering that the bump at the snowline forms later, at ~ 0.1 Myr after the beginning of the simulation.
Planetesimal formation efficiency is set at ϵ = 7.5 × 10−7.
About this article
Cite this article
Izidoro, A., Dasgupta, R., Raymond, S.N. et al. Planetesimal rings as the cause of the Solar System’s planetary architecture. Nat Astron 6, 357–366 (2022). https://doi.org/10.1038/s41550-021-01557-z
This article is cited by
Nature Astronomy (2023)
Nature Reviews Physics (2022)
Nature Astronomy (2021)