Related papers: Forming chondrules in impact splashes. I. Radiativ…
Chondrules are millimeter sized objects of spherical to irregular shape that constitute the major component of chondritic meteorites that originate in the region between Mars and Jupiter and which fall to Earth. They appear to have…
Compound chondrules, i.e. chondrules fused together, make a powerful probe of the density and compositional diversity in chondrule-forming environments, but their abundance among the dominating porphyritic textures may have been drastically…
Beneath the fusion-encrusted surfaces of the most primitive stony meteorites lies not homogeneous rock, but a profusion of millimeter-sized igneous spheres. These chondrules, and their centimeter-sized counterparts, the…
Chondrites are one of the most primitive objects in the solar system, and keep the record of the degree of thermal metamorphism experienced in their parent bodies. This thermal history can be classified by the petrologic type. We…
Recent isotopic studies of Martian meteorites by Dauphas & Pourmond (2011) have established that large (~ 3000 km radius) planetary embryos existed in the solar nebula at the same time that chondrules - millimeter-sized igneous inclusions…
We present a novel model showing that compound chondrules are formed by collisions of supercooled droplets. This model reproduces two prominent observed features of compound chondrules: the nonporphyritic texture and the size ratio between…
Impacts between planetesimals have largely been ruled out as a heat source in the early Solar System, by calculations that show them to be an inefficient heat source and unlikely to cause global heating. However, the long-term, localized…
We model the hydrodynamic interaction of a shock wave of an evolved supernova remnant with a small interstellar gas cloud like the ones observed in the Cygnus loop and in the Vela SNR. We investigate the interplay between radiative cooling…
In this paper, the possibility that the moderately volatile element depletions observed in chondritic meteorites are the results of planetesimals accreting in a solar nebula that cooled from an initially hot state (temperatures > 1350 K out…
Sheet-like clouds are common in turbulent gas and perhaps form via collisions between turbulent gas flows. Having examined the evolution of an isothermal shocked slab in an earlier contribution, in this work we follow the evolution of a…
Radiative shock waves show a strong cooling instability at temperatures above approximately 2 times 10^5 K. We numerically investigate this instability by simulating different astronomical objects in which colliding flows play an…
A chondrule formation theory is presented where the chondrule formation zone is located within 0.1 AU of the protosun. This hot, optically thick, inner zone of the solar accretion disk is coincident with the formation region of the…
Formation of the first planetesimals remains an unsolved problem. Growth by sticking must initiate the process, but multiple studies have revealed a series of barriers that can slow or stall growth, most of them due to nebula turbulence. In…
We present the results of a series of calculations studying the collapse of molecular cloud cores performed using a three-dimensional smoothed particle hydr odynamics code with radiative transfer in the flux-limited diffusion approximation.…
We propose a new scenario for compound chondrule formation named as "fragment-collision model," in the framework of the shock-wave heating model. A molten cm-sized dust particle (parent) is disrupted in the high-velocity gas flow. The…
Meteoritic chondrules were formed in the early solar system by brief heating of silicate dust to melting temperatures. Some highly refractory grains (Type B calcium-aluminum-rich inclusions, CAIs) also show signs of transient heating. A…
We have studied cloudy taenite, metallographic cooling rates, and shock effects in 30 H3-6 chondrites to elucidate the thermal and early impact history of the H chondrite parent body. We focused on H chondrites with Ar-Ar ages greater than…
In order to investigate the hypothesis that dust aggregates were transformed to meteoritic chondrules by nebular lightning, we exposed silicatic and metallic dust samples to electric discharges with energies of 120 to 500 J in air at…
We compute numerical simulations of spherical collapse triggered by a slow increase in external pressure. We compare isothermal models to models including cooling with a simple but self-consistent treatment of the coupling between gas,…
The impact of a liquid drop with high Reynolds and Weber numbers on a wet solid surface typically results in the emergence, rising, and expansion of a corona-like thin jet. This phenomenon is explained by the propagation of a kinematic…