Asteroid 4 Vesta seems to be a major intact protoplanet, with a surface composition similar to that of the HED (howardite–eucrite–diogenite) meteorites1,2,3,4. The southern hemisphere is dominated by a giant impact scar5, but previous impact models6,7,8 have failed to reproduce the observed topography. The recent discovery that Vesta’s southern hemisphere is dominated by two overlapping basins9 provides an opportunity to model Vesta’s topography more accurately. Here we report three-dimensional simulations of Vesta’s global evolution under two overlapping planet-scale collisions. We closely reproduce its observed shape, and provide maps of impact excavation and ejecta deposition. Spiral patterns observed in the younger basin Rheasilvia9, about one billion years old10, are attributed to Coriolis forces during crater collapse. Surface materials exposed in the north come from a depth of about 20 kilometres, according to our models, whereas materials exposed inside the southern double-excavation come from depths of about 60–100 kilometres. If Vesta began as a layered, completely differentiated protoplanet, then our model predicts large areas of pure diogenites and olivine-rich rocks. These are not seen11,12,13, possibly implying that the outer 100 kilometres or so of Vesta is composed mainly of a basaltic crust (eucrites) with ultramafic intrusions (diogenites).
Subscribe to Journal
Get full journal access for 1 year
only $3.90 per issue
All prices are NET prices.
VAT will be added later in the checkout.
Tax calculation will be finalised during checkout.
Rent or Buy article
Get time limited or full article access on ReadCube.
All prices are NET prices.
McCord, T. B., Adams, J. B. & Johnson, T. V. Asteroid Vesta: spectral reflectivity and compositional implications. Science 168, 1445–1447 (1970)
McCord, T. B. et al. Dark material on Vesta from the infall of carbonaceous volatile-rich material. Nature 491, 83–86 (2012)
Keil, K. in Asteroids III (eds Bottke, W. F. Jr et al.) 573–584 (Univ. Arizona Press, 2002)
Russell, C. T. et al. Dawn at Vesta: testing the protoplanetary paradigm. Science 336, 684–686 (2012)
Thomas, P. C. et al. Impact excavation on asteroid 4 Vesta: Hubble Space Telescope results. Science 277, 1492–1495 (1997)
Asphaug, E. Impact origin of the Vesta family. Meteorit. Planet. Sci. 32, 965–980 (1997)
Jutzi, M. & Asphaug, E. Mega-ejecta on asteroid Vesta. Geophys. Res. Lett.. 38, L01102, http://dx.doi.org/10.1029/2010GL045517 (2011)
Ivanov, B. A., Melosh, H. J. & Pierazzo, E. The south pole impact crater on Vesta: numerical modelling. Lunar Planet Sci Conf. 42, 1717 (2011); available at http://www.lpi.usra.edu/meetings/lpsc2011/pdf/1717.pdf.
Schenk, P. et al. The geologically recent giant impact basins at Vesta’s south pole. Science 336, 694–697 (2012)
Marchi, S. et al. The violent collisional history of asteroid 4 Vesta. Science 336, 690–694 (2012)
McSween, H. Y. et al. Dawn’s exploration of Vesta’s south pole basin — where is the mantle? 75th Annual Meteoritical Society Meeting (2012); available at http://www.lpi.usra.edu/meetings/metsoc2012/pdf/5020.pdf
De Sanctis, M. C. et al. Spectroscopic characterization of mineralogy and its diversity across Vesta. Science 336, 697–700 (2012)
Reddy, V. et al. Color and albedo heterogeneity of Vesta from Dawn. Science 336, 700–704 (2012)
Jaumann, R. et al. Vesta’s shape and morphology. Science 336, 687–690 (2012)
Housen, K. R., Schmidt, R. M. & Holsapple, K. A. Crater ejecta scaling laws: fundamental forms based on dimensional analysis. J. Geophys. Res. 88, 2485–2499 (1983)
Benz, W. & Asphaug, E. Simulations of brittle solids using smooth particle hydrodynamics. Comput. Phys. Commun. 87, 253–265 (1995)
Jutzi, M., Benz, W. & Michel, P. Numerical simulations of impacts involving porous bodies. I. Implementing sub-resolution porosity in a 3D SPH hydrocode. Icarus 198, 242–255 (2008)
Ivanov, B. A. & Melosh, H. J. The Rheasilvia crater on Vesta: numerical modelling. Lunar Planet. Sci. Conf. 43, 2148 (2012); available at http://www.lpi.usra.edu/meetings/lpsc2012/pdf/2148.pdf
Preusker, F. et al. Topography of Vesta from Dawn FC stereo images. Lunar Planet. Sci. Conf. 43, 2012 (2012); available at http://www.lpi.usra.edu/meetings/lpsc2012/pdf/2012.pdf
Takeda, H. A layered-crust model of a howardite parent body. Icarus 40, 455–470 (1979)
Ruzicka, A., Snyder, G. A. & Taylor, L. Vesta as the HED parent body: implications for the size of a core and for large-scale differentiation. Meteorit. Planet. Sci. 32, 825–840 (1997)
Righter, K. & Drake, M. J. A magma ocean on Vesta: core formation and petrogenesis of eucrites and diogenites. Meteorit. Planet. Sci. 32, 929–944 (1997)
Mittlefehldt, D. W. Petrology and geochemistry of the Elephant Moraine A79002 diogenite: a genomict breccia containing a magnesian harzburgite component. Meteorit. Planet. Sci. 35, 901–912 (2000)
Barrat, J.-A., Yamaguchi, A., Zanda, B., Bollinger, C. & Bohn, M. Relative chronology of crust formation on asteroid Vesta: insights from the geochemistry of diogenites. Geochim. Cosmochim. Acta 74, 6218–6231 (2010)
Yamaguchi, A., Barrat, J.-A., Ito, M. & Bohn, M. Posteucritic magmatism on Vesta: Evidence from the petrology and thermal history of diogenites. J. Geophys. Res.. 116, E08009, http://dx.doi.org/10.1029/2010JE003753 (2011)
Prettyman, T. H. et al. Elemental mapping by Dawn reveals exogenic H in Vesta’s regolith. Science 338, 242–246 (2012) (published online, 20 September 2012)
Beck, P. et al. NIR spectral trends of HED meteorites: can we discriminate between the magmatic evolution, mechanical mixing and observation geochemistry effects? Icarus 216, 560–571 (2011)
Collins, G. S., Melosh, H. J. & Ivanov, B. A. Modeling damage and deformation in impact simulations. Meteorit. Planet. Sci. 39, 217–231 (2004)
Melosh, H. J. & Ivanov, B. A. Impact crater collapse. Annu. Rev. Earth Planet. Sci. 27, 385–415 (1999)
M.J. acknowledges support from the Ambizione programme of the Swiss National Science Foundation. E.A. was supported by NASA’s Planetary Geology and Geophysics Program. J.-A.B. acknowledges support from the Programme National de Planétologie de l’INSU. W.B. acknowledges support from the Swiss National Science Foundation.
The authors declare no competing financial interests.
About this article
Cite this article
Jutzi, M., Asphaug, E., Gillet, P. et al. The structure of the asteroid 4 Vesta as revealed by models of planet-scale collisions. Nature 494, 207–210 (2013). https://doi.org/10.1038/nature11892
Nature Astronomy (2021)
Nature Astronomy (2020)
Nature Geoscience (2019)
Nature Geoscience (2019)
Space Science Reviews (2016)