caa a22 4500 445816252 CHVBK 20180317145229.0 cr unu---uuuuu 170323e20111201xx s 000 0 eng 10.1007/s11214-011-9806-8 doi (NATIONALLICENCE)springer-10.1007/s11214-011-9806-8 Origin, Internal Structure and Evolution of 4 Vesta [Elektronische Daten] [Maria Zuber, Harry McSween Jr., Richard Binzel, Linda Elkins-Tanton, Alexander Konopliv, Carle Pieters, David Smith] Asteroid 4 Vesta is the only preserved intact example of a large, differentiated protoplanet like those believed to be the building blocks of terrestrial planet accretion. Vesta accreted rapidly from the solar nebula in the inner asteroid belt and likely melted due to heat released due to the decay of 26Al. Analyses of meteorites from the howardite-eucrite-diogenite (HED) suite, which have been both spectroscopically and dynamically linked to Vesta, lead to a model of the asteroid with a basaltic crust that overlies a depleted peridotitic mantle and an iron core. Vesta's crust may become more mafic with depth and might have been intruded by plutons arising from mantle melting. Constraints on the asteroid's moments of inertia from the long-wavelength gravity field, pole position and rotation, informed by bulk composition estimates, allow tradeoffs between mantle density and core size; cores of up to half the planetary radius can be consistent with plausible mantle compositions. The asteroid's present surface is expected to consist of widespread volcanic terrain, modified extensively by impacts that exposed the underlying crust or possibly the mantle. Hemispheric heterogeneity has been observed by poorly resolved imaging of the surface that suggests the possibility of a physiographic dichotomy as occurs on other terrestrial planets. Vesta might have had an early magma ocean but details of the early thermal structure are far from clear owing to model uncertainties and paradoxical observations from the HEDs. Petrological analysis of the eucrites coupled with thermal evolution modeling recognizes two possible mechanisms of silicate-metal differentiation leading to the formation of the basaltic achondrites: equilibrium partial melting or crystallization of residual liquid from the cooling magma ocean. Afirmer understanding the plethora of complex physical and chemical processes that contribute to melting and crystallization will ultimately be required to distinguish among these possibilities. The most prominent physiographic feature on Vesta is the massive south polar basin, whose formation likely re-oriented the body axis of the asteroid's rotation. The large impact represents the likely major mechanism of ejection of fragments that became the HEDs. Observations from the Dawn mission hold the promise of revolutionizing our understanding of 4 Vesta, and by extension, the nature of collisional, melting and differentiation processes in the nascent solar system. Springer Science+Business Media B.V., 2011 Vesta nationallicence Asteroid nationallicence Crust nationallicence Mantle nationallicence Core nationallicence Evolution nationallicence Impact nationallicence Zuber Maria Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, 02139-4307, Cambridge, MA, USA aut McSween Jr. Harry Planetary Geoscience Institute and Department of Earth & Planetary Sciences, University of Tennessee, 37996-1410, Knoxville, TN, USA aut Binzel Richard Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, 02139-4307, Cambridge, MA, USA aut Elkins-Tanton Linda Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, 02139-4307, Cambridge, MA, USA aut Konopliv Alexander Jet Propulsion Laboratory, 91109, Pasadena, CA, USA aut Pieters Carle Department of Geological Sciences, Box 1846, Brown University, 02912, Providence, RI, USA aut Smith David Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, 02139-4307, Cambridge, MA, USA aut Space Science Reviews Springer Netherlands 163/1-4(2011-12-01), 77-93 0038-6308 163:1-4<77 2011 163 11214 https://doi.org/10.1007/s11214-011-9806-8 text/html Onlinezugriff via DOI 1 review-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s11214-011-9806-8 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Zuber Maria Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, 02139-4307, Cambridge, MA, USA aut NATIONALLICENCE 700 1- McSween Jr Harry Planetary Geoscience Institute and Department of Earth & Planetary Sciences, University of Tennessee, 37996-1410, Knoxville, TN, USA aut NATIONALLICENCE 700 1- Binzel Richard Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, 02139-4307, Cambridge, MA, USA aut NATIONALLICENCE 700 1- Elkins-Tanton Linda Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, 02139-4307, Cambridge, MA, USA aut NATIONALLICENCE 700 1- Konopliv Alexander Jet Propulsion Laboratory, 91109, Pasadena, CA, USA aut NATIONALLICENCE 700 1- Pieters Carle Department of Geological Sciences, Box 1846, Brown University, 02912, Providence, RI, USA aut NATIONALLICENCE 700 1- Smith David Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, 02139-4307, Cambridge, MA, USA aut NATIONALLICENCE 773 0- Space Science Reviews Springer Netherlands 163/1-4(2011-12-01), 77-93 0038-6308 163:1-4<77 2011 163 11214 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer