Laboratory evidence for co-condensed oxygen- and carbon-rich meteoritic stardust from nova outbursts

Abstract

Although their parent stars no longer exist, the isotopic and chemical compositions and microstructure of individual stardust grains identified in meteorites provide unique constraints on dust formation and thermodynamical conditions in stellar outflows 1-4. Novae are stellar explosions that take place in the hydrogen-rich envelope accreted onto the surface of a white dwarf in a close binary system 5. The energy released by a suite of nuclear processes operating in the envelope 2 powers a thermonuclear runaway, resulting in the ejection of processed material into the interstellar medium. Spectral fitting of features observed in the infrared spectra of dust-forming novae provided the first evidence of the co-condensation of both carbonaceous and silicate dust in stellar outflows within the 50 to 100 days after explosion 6-11. Here we report the identification of an O-rich inclusion, composed of both silicate and oxide nanoparticles, inside a graphite spherule that originated in the ejecta of a low-mass CO nova 12. This observation provides laboratory evidence of the co-condensation of O-and C-rich dust in nova outbursts, and is consistent with the transport and mixing of materials between chemically distinct clumps within the nova ejecta. Dust in stellar and interstellar environments is traditionally studied using space or ground-based telescopes but the laboratory study of circumstellar (presolar) grains identified in extraterrestrial materials (e.g., meteorites) has opened up a new field in astronomy and astrophysics, providing direct ground-truth information on individual stars. Such presolar grains are nanometer-to micrometer-sized minerals, amorphous grains, or aggregates of them, and can include materials such as nanodiamond, SiC, graphites, oxides, and silicates 1,2. Over the last two decades, about 2000 presolar graphite spherules have been identified and studied exclusively from the acid-resistant residues of the three carbonaceous chondrites: Murchison (CM2), Orgueil (CI1), and Qingzhen (EH3) 13-15. While most presolar graphite spherules originated from lowmetallicity asymptotic-giant-branch stars (∼50%) and core-collapse supernovae (∼25%), the remaining grains are hypothesized to have also originated from other types of stars, e.g., born-again AGB and Jtype stars 14,15. A few presolar graphite grains also have isotopic compositions suggesting possible origins in the ejecta of novae 16. Novae are traditionally classified as neon and non-neon, which reflects the composition of the white dwarf that hosts the explosion, i.e., ONe (O-and Ne-rich) and CO (C-and O-rich), respectively 5. Similarly to other SiC, silicates, and oxides with putative nova origins, these

Coordinated chemical and microstructural analyses of presolar silicate grains from AGB/RGB stars and supernovae in the CO3.0 chondrite Dominion Range 08006

“…To date, more than 1500 O‐rich presolar grains have been identified with stellar origins including RGB, AGB stars, novae, and SNe (e.g., Bose et al., 2010, 2012, 2014; Busemann et al., 2009; Choi et al., 1998, 1999; Davidson et al., 2012, 2014, 2015; Ebata et al., 2006; Floss et al., 2006, 2010, 2013; Floss & Stadermann, 2009a, 2009b, 2012; Gyngard, Nittler, et al., 2010; Gyngard, Zinner, et al., 2010; Haenecour et al., 2013, 2018, 2019, 2020; Huss et al., 1994; Keller & Messenger, 2011; Leitner et al., 2012, 2014, 2016, 2020; Messenger et al., 2003, 2005; Mostefaoui & Hoppe, 2004; Nagashima et al., 2004; Nguyen & Messenger, 2014; Nguyen et al., 2007, 2010; Nguyen & Zinner, 2004; Nittler et al., 1994, 1997, 1998, 2008, 2018; Tonotani et al., 2006; Vollmer et al., 2009; Zhao et al., 2010, 2011, 2013; Zinner et al., 2003, 2005). Of the grains identified in meteorites, only ~10% are attributed to origins in the ejecta of SNe (Haenecour et al., 2018), though as previously mentioned, recent nucleosynthetic modeling suggests this fraction could be much higher, as some Group 1 and Group 2 presolar silicate grains could originate in SNe (Hoppe et al., 2021; Leitner & Hoppe, 2019; Verdier‐Paoletti et al., 2019).…”

“…Electron transparent cross sections (<100 nm in projected thickness) of the selected grains were prepared for detailed structural and chemical analyses using the Thermo Fisher Scientific (formerly FEI) Helios G 3 focused ion beam scanning electron microscope (FIB-SEM) located in the Kuiper Materials Imaging and Characterization Facility (KMICF) at the Lunar and Planetary Laboratory (LPL), University of Arizona. The procedure for producing electron transparent cross sections of presolar grains was described in many papers (Haenecour et al, 2019(Haenecour et al, , 2020Holzapfel et al, 2009;Leitner et al, 2012Leitner et al, , 2016Nguyen et al, 2007Nguyen et al, , 2016Stroud et al, 2004;Vollmer et al, 2007Vollmer et al, , 2009Vollmer et al, , 2013Zega et al, 2007Zega et al, , 2011Zega et al, , 2014Zega et al, , 2015Zega et al, , 2020. Briefly, we first go through an alignment procedure to ensure that we capture the anomalous region of interest, initially identified with NanoSIMS, in our FIB transect.…”

“…To date, more than 1500 O-rich presolar grains have been identified with stellar origins including RGB, AGB stars, novae, and SNe (e.g., Bose et al, 2010Bose et al, , 2012Bose et al, , 2014Busemann et al, 2009;Choi et al, 1998Choi et al, , 1999Davidson et al, 2012Davidson et al, , 2014Davidson et al, , 2015Ebata et al, 2006;Floss et al, 2006Floss et al, , 2010Floss et al, , 2013Floss & Stadermann, 2009a, 2009bHaenecour et al, 2013Haenecour et al, , 2018Haenecour et al, , 2019Haenecour et al, , 2020Huss et al, 1994;Keller & Messenger, 2011;Leitner et al, 2012Leitner et al, , 2014Leitner et al, , 2016Leitner et al, , 2020Messenger et al, 2003Messenger et al, , 2005Mostefaoui & Hoppe, 2004;Nagashima et al, 2004;Nguyen et al, 2007Nguyen et al, , 2010Nguyen & Zinner, 2004;Nittler et al, 1994Nittler et al, , 1997Nittler et al, , 1998Nittler et al, , 2008Nittler et al, , 2018Tonotani et al, 2006;Vollmer et al, 2009;Zhao et al, 2010...…”

An in situ investigation of the preservation and alteration of presolar silicates in the Miller Range 07687 chondrite

“…Electron transparent (<100 nm in projected thickness) cross-sections of four grains were prepared using the Thermo Fisher Scientific (formerly FEI) Helios G 3 focused-ion beam scanning-electron microscope (FIB-SEM) located in the Kuiper Materials Imaging and Characterization Facility (KMICF) at the Lunar and Planetary Laboratory (LPL), University of Arizona. The general procedure for producing electron transparent cross-sections of presolar grains is described in several previous papers (e.g., Haenecour et al, 2019Haenecour et al, , 2020Holzapfel et al, 2009;Seifert et al, 2022c;Zega et al, 2007Zega et al, , 2011Zega et al, , 2014bZega et al, , 2015Zega et al, , 2020. Briefly, we first go through an alignment procedure, described in detail in Seifert et al (2022c) to ensure that we capture the presolar grain identified in the NanoSIMS with our FIB transect.…”

An in situ study of presolar grains and the fine‐grained matrices of the Meteorite Hills 00526 and Queen Alexandra Range 97008 unequilibrated ordinary chondrites

“…Electron-transparent sections (<100 nm in projected thickness) of five grains, three from MET 00526 and two from QUE 97008 and three matrix sections were prepared using the Thermo Fisher Scientific (formerly FEI) Helios G 3 focused ion beam-scanning electron microscope (FIB-SEM) located in the Kuiper Materials Imaging and Characterization Facility (KMICF) at the Lunar and Planetary Laboratory (LPL), University of Arizona. We followed previously described procedures for producing electron-transparent cross sections of presolar grains, which is described in detail in the literature (Haenecour et al, 2019(Haenecour et al, , 2020Holzapfel et al, 2009;Leitner et al, 2012Leitner et al, , 2016Nguyen et al, 2007Nguyen et al, , 2016Seifert et al, 2022Seifert et al, , 2023Stroud et al, 2004;Vollmer et al, 2007Vollmer et al, , 2009Vollmer et al, , 2013Zega et al, 2007Zega et al, , 2011Zega et al, , 2014Zega et al, , 2015Zega et al, , 2020.…”