000011024 001__ 11024 000011024 005__ 20250218124738.0 000011024 02470 $$ahttps://doi.org/10.1126/sciadv.aba1303$$2doi 000011024 037__ $$aTEXTUAL 000011024 037__ $$bArticle 000011024 041__ $$aeng 000011024 245__ $$aMeteorite evidence for partial differentiation and protracted accretion of planetesimals 000011024 269__ $$a2020-07-24 000011024 336__ $$aArticle 000011024 520__ $$aModern meteorite classification schemes assume that no single planetary body could be source of both unmelted (chondritic) and melted (achondritic) meteorites. This dichotomy is a natural outcome of formation models assuming that planetesimal accretion occurred nearly instantaneously. However, it has recently been proposed that the accretion of many planetesimals lasted over ≳1 million years (Ma). This could have resulted in partially differentiated internal structures, with individual bodies containing iron cores, achondritic silicate mantles, and chondritic crusts. This proposal can be tested by searching for a meteorite group containing evidence for these three layers. We combine synchrotron paleomagnetic analyses with thermal, impact, and collisional evolution models to show that the parent body of the enigmatic IIE iron meteorites was such a partially differentiated planetesimal. This implies that some chondrites and achondrites simultaneously coexisted on the same planetesimal, indicating that accretion was protracted and that apparently undifferentiated asteroids may contain melted interiors. 000011024 536__ $$oU.S. Department of Energy$$cDE-AC02-05CH11231 000011024 536__ $$oNASA$$cNNX15AH72G$$aEmerging Worlds Program 000011024 536__ $$oNASA$$cNNM16AA09C$$aDiscovery Program 000011024 536__ $$oUniversity of Cambridge 000011024 540__ $$a<p>Copyright © 2020 The Authors</p> <p>This is an open-access article distributed under the terms of the&nbsp;<a href="https://creativecommons.org/licenses/by-nc/4.0/">Creative Commons Attribution-NonCommercial license</a>, which permits use, distribution, and reproduction in any medium, so long as the resultant use is&nbsp;<span>not</span>&nbsp;for commercial advantage and provided the original work is properly cited.</p> 000011024 542__ $$fCC BY-NC 000011024 594__ $$aThe raw XPEEM data are publicly available on the Magnetic Information Consortium (MagIC) database at earthref.org/MagIC/16837. All other data needed to evaluate the conclusions in the paper are present in the paper and/or the Supplementary Materials. 000011024 690__ $$aPhysical Sciences Division 000011024 691__ $$aGeophysical Sciences 000011024 7001_ $$1https://orcid.org/0000-0002-4257-5318$$2ORCID$$aMaurel, Clara$$uMassachusetts Institute of Technology 000011024 7001_ $$1https://orcid.org/0000-0002-5675-8545$$2ORCID$$aBryson, James F.J.$$uUniversity of Cambridge 000011024 7001_ $$1https://orcid.org/0000-0002-0474-9153$$2ORCID$$aLyons, Richard J.$$uUniversity of Chicago 000011024 7001_ $$1https://orcid.org/0000-0003-3058-7968$$2ORCID$$aBall, Matthew R.$$uUniversity of Cambridge 000011024 7001_ $$1https://orcid.org/0000-0001-6727-6501$$2ORCID$$aChopdekar, Rajesh V.$$uLawrence Berkeley National Laboratory 000011024 7001_ $$1https://orcid.org/0000-0002-1990-4769$$2ORCID$$aScholl, Andreas$$uLawrence Berkeley National Laboratory 000011024 7001_ $$1https://orcid.org/0000-0002-0093-065X$$2ORCID$$aCiesla, Fred J.$$uUniversity of Chicago 000011024 7001_ $$1https://orcid.org/0000-0002-1804-7814$$2ORCID$$aBottke, William F.$$uSouthwest Research Institute 000011024 7001_ $$1https://orcid.org/0000-0003-3113-3415$$2ORCID$$aWeiss, Benjamin P.$$uMassachusetts Institute of Technology 000011024 773__ $$tScience Advances 000011024 8564_ $$yArticle$$9e1917466-bb0a-4703-80c8-b466f2c534e4$$s1221814$$uhttps://knowledge.uchicago.edu/record/11024/files/sciadv.aba1303.pdf$$ePublic 000011024 8564_ $$ySupplementary materials$$974e5b29b-788e-4f50-8ac6-517b27c32575$$s11569991$$uhttps://knowledge.uchicago.edu/record/11024/files/aba1303_sm.pdf$$ePublic 000011024 908__ $$aI agree 000011024 909CO $$ooai:uchicago.tind.io:11024$$pGLOBAL_SET 000011024 983__ $$aArticle