相关论文: Generating potassium abundance variations in the S…
The size distribution of asteroids and Kuiper belt objects in the solar system is difficult to reconcile with a bottom-up formation scenario due to the observed scarcity of objects smaller than $\sim$100 km in size. Instead, planetesimals…
The basic structure of the solar system is set by the presence of low-mass terrestrial planets in its inner part and giant planets in its outer part. This is the result of the formation of a system of multiple embryos with approximately the…
The formation of planetesimals is expected to occur via particle-gas instabilities that concentrate dust into self-gravitating clumps. Triggering these instabilities requires the prior pileup of dust in the protoplanetary disk. Until now,…
Aspects of our Solar System's formation are deduced from observations of the chemical nature of matter. Massive cores are indicative of terrestrial-planet-composition-similarity to enstatite chondrite meteorites, whose highly-reduced state…
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…
Low-mass, metal-enriched stars were likely present as early as cosmic dawn. In this work, we investigate whether these stars could have hosted planets in their protoplanetary disks. If so, these would have been the first planets to form in…
The Martian isotopic record displays a dichotomy in volatile compositions. Interior volatiles from the mantle record a chondritic heritage (e.g., H, N, Kr, Xe) whereas the atmospheric reservoir of Kr and Xe - which do not currently…
Crystalline silicates are found in a large number of comets. These pose a long-standing conundrum for solar system formation models as they can only be created in the inner hot disk at temperatures higher than 800 K, and there is no obvious…
Peak temperatures inside meteorite parent bodies are closely linked to accretion times. Most iron meteorites come from bodies that accreted <0.5 Myr after CAIs formed and were melted by 26Al and 60Fe, probably inside 2 AU. Chondrite groups…
"Pebble snow" describes a planet formation mechanism where icy pebbles in the outer disk reach inner planet embryos as the water ice line evolves inward. We model the effects pebble snow has on sculpting planetary system architectures by…
A persistent question in exoplanet demographics is whether exoplanetary systems form from similar compositional building blocks to our own. Polluted white dwarf stars offer a unique way to address this question as they provide measurements…
The effect of a nearby $\gamma$-ray burst (GRB) on the preplanetary solar nebula is considered. The intense irradiation by x-rays and $\gamma$-rays would have caused dust balls to become molten in a matter of seconds, cooling more slowly to…
Transition disks have dust-depleted inner regions and may represent an intermediate step of an on-going disk dispersal process, where planet formation is probably in progress. Recent millimetre observations of transition disks reveal…
Dust particles immersed within a plasma environment, such as those found in planetary rings or comets, will acquire an electric charge. If the ratio of the inter-particle potential energy to average kinetic energy is large enough the…
Several lines of evidence suggest that fine silicate crystals observed in primitive meteorite and interplanetary dust particles (IDPs) nucleated in a supersaturated silicate vapor followed by crystalline growth. We investigated evaporation…
We investigate the formation of planetesimals via the gravitational instability of solids that have settled to the midplane of a circumstellar disk. Vertical shear between the gas and a subdisk of solids induces turbulent mixing which…
Although dust is widely found in astrophysics, forming dust is surprisingly difficult. The proper combination of low temperature (<2000 K) and high density is mainly found in the winds of late-type giant and supergiant stars which, as a…
Stardust grains recovered from meteorites provide high-precision snapshots of the isotopic composition of the stellar environment in which they formed. Attributing their origin to specific types of stars, however, often proves difficult.…
Massive cores of the giant planets are thought to have formed in a gas disk by accretion of pebble-size particles whose accretional cross-section is enhanced by aerodynamic gas drag [1][2]. A commonly held view is that the terrestrial…
We explore here the idea, reminiscent in some respect of Von Weizsacker's (1944) and Alfven's (1976) outmoded cosmogonies, that long-lived vortices in a turbulent protoplanetary nebula can capture large amount of solid particles and…