McKeegan, Kevin D.Aleon, JeromeBradley, JohnBrownlee, DonaldBusemann, HennerButterworth, AnnaChaussidon, MarcFallon, StewartFloss, ChristineGilmour, JamieGounelle, MatthieuGraham, GilesGuan, YunbinHeck, Philipp R.Hoppe, PeterHutcheon, Ian D.Huth, JoachimIshii, HopeIto, MotooJacobsen, Stein B.Kearsley, AntonLeshin, Laurie A.Liu, Ming-ChangLyon, IanMarhas, KuljeetMarty, BernardMatrajt, GracielaMeibom, AndersMessenger, ScottMostefaoui, SmailMukhopadhyay, SujoyNakamura-Messenger, KeikoNittler, LarryPalma, RussPepin, Robert O.Papanastassiou, Dimitri A.Robert, FrancoisSchlutter, DennisSnead, Christopher J.Stadermann, Frank J.Stroud, RhondaTsou, PeterWestphal, AndrewYoung, Edward D.Ziegler, KarenZimmermann, LaurentZinner, Ernst2012-05-152012-05-152012-05-15200610.1126/science.1135992https://infoscience.epfl.ch/handle/20.500.14299/80442Hydrogen, carbon, nitrogen, and oxygen isotopic compositions are heterogeneous among comet 81P/Wild 2 particle fragments; however, extreme isotopic anomalies are rare, indicating that the comet is not a pristine aggregate of presolar materials. Nonterrestrial nitrogen and neon isotope ratios suggest that indigenous organic matter and highly volatile materials were successfully collected. Except for a single O-17-enriched circumstellar stardust grain, silicate and oxide minerals have oxygen isotopic compositions consistent with solar system origin. One refractory grain is O-16-enriched, like refractory inclusions in meteorites, suggesting that Wild 2 contains material formed at high temperature in the inner solar system and transported to the Kuiper belt before comet accretion.Interplanetary Dust ParticlesCrystalline SilicatesHale-BoppOxygen IsotopesOrganic-MatterMeteoritesNitrogenPresolarOriginRatiostext::journal::journal article::research article