Meeting Planning Services

8:30 AM

Smith L. R.* Haenecour P. Barnes J. J. Bloch E. Domanik K.

Presolar Grains in the C2-Ungrouped Chondrite Tarda [#6077]
We carried out an in situ presolar grain search and characterization of the mineralogy and petrology in Tarda. This work is part of an effort to constrain how aqueous alteration affects the abundance, composition, and mineralogy of presolar grains.

8:45 AM

Hashizume H. H.* Takigawa A. T. Nittler L. N.

In-Situ Study of Presolar Al-Rich Oxide Grains in CO3 Chondrite Dominion Range 08006 [#6306]
We derived the abundance ratio of presolar/solar Al-rich oxides in a matrix of a carbonaceous chondrite for the first time as 3.0±0.8% and demonstrated crystal and elemental structures of a non-stoichiometric presolar spinel by TEM.

9:00 AM

Korsmeyer J. M.* Stephan T. Zheng Y. Davis A. M. Nittler L. R. et al.

Presolar Silicon Carbide Grains Separated from CM2 Meteorite Aguas Zarcas [#6358]
We present a modified presolar grain separation procedure based on the University of Chicago method that maximizes the variety of presolar grains and minerals recovered while avoiding any steps that would restrict future analyses.

9:15 AM

Bernal J. J.*

Silicon Carbide Presolar Grain Decomposition: Implications for the Synthesis of Fullerenic Carbon in the Allende Chondrite [#6411]
Heating analog SiC grains at elevated temperatures results in total decomposition of the SiC, leaving remnant graphitic carbon layers yielding carbon nano-onions and “bamboo” carbon nanotube structures, reported in the Allende meteorite.

9:30 AM

Liu N.* Alexander C. M. O'D. Wang J.

Sulfur Isotopic Compositions of Presolar Silicon Carbide Grains [#6020]
We report S isotopic anomalies of two X, one C, one mainstream, and one Z SiC grain. The S isotopic anomalies of the C and X grains point to the initial presence of radioactive 32Si produced by neutron bursts during supernova explosions.

9:45 AM

Leitner J.* Hoppe P. Trieloff M.

Magnesium Isotope Heterogeneities in Supernova Silicates [#6275]
We report Mg isotope heterogeneities in three magnesium-25-rich silicates of likely supernova origin. Sub-grain compositions are in line with a formation sequence covering a certain mass range within the O/nova zone of supernovae with H-ingestion.

10:00 AM

Nittler L. R.* Kraver C. Bose M. Williams P.

High Spatial Resolution Isotopic Measurements of Presolar Silicates with a Modified Duoplasmatron Oxygen Negative Ion Source [#6465]
Tiny O3 beam / From a duoplasmatron / Measure Stardust grain.

10:15 AM

Stephan T.* Davis A. M. Gyngard F. Hoppe P. Hynes K. M. et al.

The Presolar Grain Database Reloaded — Graphite [#6388]
We present the new Presolar Grain Database for graphite grains, which has been rebuilt from the ground up, correcting data in the old database from 2009 and adding new data. The database now contains data for 2122 individual presolar graphite grains.

10:30 AM

Takigawa A.* Ueda H.

Low-Temperature Condensation of Silicate Under Water Vapor [#6304]
We conducted condensation experiments of Si-Mg-O gases with/without a water vapor flow at room and low temperatures in a new MBE system. Water vapor enhances the formation of crystalline forsterite during condensation of amorphous silicates.

10:45 AM

Enomoto H.* Takigawa A.

Constraining Chemical Composition of Dust Around AGB Stars: Experiments and Spectroscopy of Amorphous Silicate [#6353]
From experiments and spectroscopy of amorphous silicate with systematic change in Al and Ca content, dust around AGB stars is estimated to be Al-rich amorphous silicate contrary to scarcity of Al-rich presolar silicate grain.

11:00 AM

Meyer B. S.* Walls L. S.

Analytic Models for Neutron-Burst Nucleosynthesis [#6420]
We present analytic models of neutron-burst nucleosynthesis, which allow users to study the role of key inputs such as initial abundances and cross sections on final yields. This facilitates comparison with supernova grain data.

11:15 AM

Adams G. M.* Lodders K.

Effects of Metallicity on Graphite, TiC, and SiC Condensation in Carbon Stars [#6198]
Reporting new condensation sequence calculations for carbon-bearing condensates in presolar grains.

11:30 AM

Borderes-Motta G. Gritsevich M.* Kastinen D. Kero J.

On the Journey of the Meteoroids Ejected from 12P/Pons-Brooks During the Outbursts of 2023–2024 [#6270]
In the present work, we aim to study the evolution of the material ejected by 12P/PONS-BROOKS’ outbursts observed in the most recent perihelion passage, focusing on the fate of this material and eventual meteor showers on Earth.

11:45 AM

Van Maldeghem F.* Goderis S. Hyde W. R. Vandoorne W. Claeys P.

Exploring Cosmic Dust: Insights from Sedimentary Traps in Western Greenland [#6271]
We present the first results of a new Arctic micrometeorite collection from Greenlandic sediment traps and compare these to the physicochemical characteristics of the Antarctic micrometeorite collections.