Related papers: Early evolution of the solar accretion disk inferr…
We report in situ LA-ICP-MS trace element analyses of silicate phases in olivine-bearing chondrules in the Sahara 97096 (EH3) enstatite chondrite. Most olivine and enstatite present rare earth element (REE) patterns comparable to their…
Aims: Interstellar molecules form early in the evolutionary sequence of interstellar material that eventually forms stars and planets. To understand this evolutionary sequence, it is important to characterize the chemical composition of its…
We determined the metal/silicate partition coefficients of hydrogen and carbon, DH and DC, simultaneously under typical conditions of Earth's core formation. Experiments demonstrate that both DH and DC diminish in the presence of carbon and…
Observations have revealed evidence of photochemical processing in protoplanetary disks. This processing occurs in the photon dominated layer, the optically thin regions of the disk high above the disk midplane. It remains unclear, however,…
Isotopic ratios have been used as chemical diagnostics to investigate the origin of the material in the Solar System. We have determined the HCN, HNC, and N2H+ isotopic ratios and the chemical age in a large sample of 23 starless cores…
We developed an experimental setup to test the hypothesis that accretionary dust rims around chondrules formed in the solar nebula at elevated temperatures. Our experimental method allows us to form dust rims around chondrule-analogs while…
This study reports the bulk rare earth element (REEs, La-Lu) compositions of 41 chondrites, including 32 falls and 9 finds from carbonaceous (CI, CM, CO and CV), enstatite (EH and EL) and ordinary (H, L and LL) groups, as well as 2…
The isotopic compositions of terrestrial hydrogen and nitrogen are clearly different from those of the nebular gas from which the solar system formed, and also differ from most of cometary values. Terrestrial N and H isotopic compositions…
We report isotopic data for a total of 96 presolar oxide grains found in residues of several unequilibrated ordinary chondrite meteorites. Identified grain types include Al2O3, MgAl2O4, hibonite (CaAl12O19) and Ti oxide. This work greatly…
How do planetary systems, in general, and our own Solar System (SS), in particular, form? In conjunction, Astronomy and Isotope Cosmochemistry provide us with powerful tools to answer this age-old question. In this contribution, we review…
This study investigated the consistency/inconsistency of carbon isotope compositions of chlorine-isotopologue pairs, e.g., 12C235Cl4 vs. 12C13C35Cl4, of individual organochlorines including two chloroethylenes, three polychlorinated…
Mid-infrared observations of planet-forming disks reveal a wide diversity in molecular spectra. Carbon and oxygen abundances play a central role in setting the chemical environment of the inner disk and the spectral appearance. We aim to…
It has been suggested that chondrules and calcium-aluminum-rich inclusions (CAIs) were formed at the inner edge of the protoplanetary disk and then entrained in magnetocentrifugal X-winds. We study trajectories of such solid bodies with the…
The most abundant matrix minerals in chondritic meteorites, hydrated phyllosilicates and ferrous olivine crystals, formed predominantly in asteroids during fluid-assisted metamorphism. We infer that they formed from minerals present in…
We report the identification of 19 presolar oxide grains from the Orgueil CI meteorite with substantial enrichments in $^{54}$Cr, with $^{54}$Cr/$^{52}$Cr ratios ranging from 1.2 to 56 times the solar value. The most enriched grains also…
Observations from Spitzer and ground-based infrared spectroscopy reveal significant diversity in the molecular emission from the inner few AU of T Tauri disks. We explore theoretically the possible origin of this diversity by expanding on…
We present a model of the early chemical composition and elemental abundances of planetary atmospheres based on the cumulative gaseous chemical species that are accreted onto planets forming by core accretion from evolving protoplanetary…
We report on studies of Classical Nova (CN) explosions where we follow the evolution of thermonuclear runaways (TNRs) on Carbon Oxygen (CO) white dwarfs (WDs). We vary both the mass of the WD (from 0.6 M$_\odot$ to 1.35 M$_\odot$) and the…
The formation of chondrules in the protoplanetary nebulae causes many questions concerning the formation process, the source of energy for melting the rims, and the composition of the origin material. The aim of this work is to explore the…
During the final assembly of gas giant planets, circumplanetary disks (CPDs) of gas and dust form due to the conservation of angular momentum, providing material to be accreted onto the planet and the ingredients for moons. The composition…