相关论文: Chondrules and Nebular Shocks
Laboratory analyses on fine-grained diamond residues from primitive meteorites have shown that nano-diamonds represent the most abundant form of presolar dust preserved in meteoritic samples. The presolar diamonds carry isotopic anomalies…
Chondrites are the likely building blocks of Earth, and identifying the group of chondrite that best represents Earth is a key to resolving the state of the early Earth. The origin of chondrites, however, remains controversial partly…
Chondritic components such as chondrules and matrix are the key time capsules that can help us understand the evolution and dynamics of the protoplanetary disk from which the Solar System originated. Knowledge of where and how these…
The lifetime of mm size dust grains, such as chondrules, in the nominal solar nebula model is limited to $\sim 10^{5}$ yr due to an inward drift driven by gas drag. However, isotopic and petrological studies on primitive meteorites indicate…
The solar nebula contained a number of short-lived radionuclides (SLRs) with half-lives of tens of Myr or less, comparable to the timescales for formation of protostars and protoplanetary disks. Therefore, determining the origins of SLRs…
Radioisotopic ages for meteorites and their components provide constraints on the evolution of small bodies: timescales of accretion, thermal and aqueous metamorphism, differentiation, cooling and impact metamorphism. Realising that the…
Cool a piece of the Sun to 1000 K at one millibar pressure to yield a mineral assemblage consistent with those found in the most primitive meteorites. This is an equilibrium or fractional condensation experiment simulated by calculations…
Observations of comets and asteroids show that the Solar Nebula that spawned our planetary system was rich in water and organic molecules. Bombardment brought these organics to the young Earth's surface, seeding its early chemistry. Unlike…
We use a newly developed cascade model of turbulent concentration of particles in protoplanetary nebulae to calculate several properties of interest to the formation of primitive planetesimals and to the meteorite record. The model follows,…
Chondrules formed by the melting of dust aggregates in the solar protoplanetary disk and as such provide unique insights into how solid material was transported and mixed within the disk. Here we show that chondrules from enstatite and…
Carbonaceous chondrites are samples from planetesimals that formed 2-4 million years after solar system formation began. They consist of distinct dust components formed at different times and locations in the accretion disk and whose…
The nearest accretion disc to us in space if not time was the protosolar nebula. Remnants of this nebula thus potentially offer unique insight into how discs work. In particular the existence of chondrules, which must have formed in the…
Composition of terrestrial planets records planetary accretion, core-mantle and crust-mantle differentiation, and surface processes. Here we compare the compositional models of Earth and Mars to reveal their characteristics and formation…
Chemical and chronological information preserved in meteorites permits the reconstruction of events and processes in the solar nebula from the formation of the first solids to the accretion of planetary bodies and their subsequent…
The supersolar abundances of volatiles observed in giant planets suggest that a compositional gradient was present at the time of their formation in the protosolar nebula. To explain this gradient, several studies have investigated the…
The early Solar System contained short-lived radionuclides such as 60Fe (t1/2 = 1.5 Myr) whose most likely source was a nearby supernova. Previous models of Solar System formation considered a supernova shock that triggered the collapse of…
The examination of the physical properties of chondrules has generally received less emphasis than other properties of meteorites such as their mineralogy, petrology, and chemical and isotopic compositions. Among the various physical…
Chondrules are thought to have formed during transient flash-heating events in dust-enriched regions of the solar protoplanetary disk. Although laboratory studies have characterized the oxygen isotopic compositions of chondritic materials,…
The construction of models for the internal constitution and the temporal evolution of large planetesimals, the parent bodies of chondrites, requires information on the heat conductivity of the complex mixture of minerals and iron metal…
Chondrules are millimeter-sized spherules that dominate primitive meteorites (chondrites) originating from the asteroid belt. The incorporation of chondrules into asteroidal bodies must be an important step in planet formation, but the…