Related papers: Stardust findings. Implications for panspermia
We review the observational evidence for dust formation in Wolf-Rayet binary systems and in Type II Supernova ejecta. Existing theoretical models describing the condensation of solids in carbon-rich Wolf-Rayet stars and in Supernovae close…
We present deep 1.2 millimeter photometry of 37 stars in the young (5 Myr) Upper Scorpius OB association, sensitive to ~4 x 10^-3 Mjup of cool millimeter dust. Disks around four low- and solar-mass stars are detected, as well as one debris…
A possible connection between the presence of large quantities of warm (T$\geq$200 K) circumstellar dust at youthful stars and the existence of wide-separation companion stars has been noted in the literature. Here we point out the…
A scenario is presented for the formation of first life in the universe based on hydro-gravitational-dynamics (HGD) cosmology. From HGD, the dark matter of galaxies is H-He gas dominated planets (primordial-fog-particle PFPs) in million…
The final expulsion of gas by a star as it forms a planetary nebula --- the ionized shell of gas often observed surrounding a young white dwarf --- is one of the most poorly understood stages of stellar evolution. Such nebulae form…
We examine a low energy mechanism for the transfer of meteoroids between two planetary systems embedded in a star cluster using quasi-parabolic orbits of minimal energy. Using Monte Carlo simulations, we find that the exchange of meteoroids…
Stars form out of molecular gas and supply dust grains during their last evolutionary stages; in turn hydrogen molecules (H2) are produced more efficiently on dust grains. Therefore, dust can drastically accelerate H2 formation, leading to…
Several structures have been discovered embedded in regions of recent or ongoing star formation, which point to the importance of the interaction between fast moving wind-blowing stars and their environment. Using hydrodynamic simulations,…
Nanodust, which undergoes stochastic heating by single starlight photons in the interstellar medium, ranges from angstrom-sized large molecules containing tens to thousands of atoms (e.g. polycyclic aromatic hydrocarbon molecules) to grains…
Massive present-day early-type (elliptical and lenticular) galaxies probably gained the bulk of their stellar mass and heavy elements through intense, dust-enshrouded starbursts - that is, increased rates of star formation - in the most…
In January 2006, the Stardust mission will return the first samples from a solid solar-system body since Apollo, and the first samples of contemporary interstellar dust ever collected. Although sophisticated laboratory instruments exist for…
Observations indicate that large, dust-laden protoplanetary discs are common. Some features, like gaps, rings and spirals, suggest they may host young planets, which can excite the orbits of nearby leftover planetesimals. Energetic…
After the discovery of a substellar companion to the hot subdwarf HD 149382, we have started a radial velocity search for similar objects around other bright sdB stars using the Anglo-Australian Telescope. Our aim is to test the hypothesis…
Many nearby stars are surrounded by a bright ring or disk of cold dust. Our calculations show that these disks and rings of dust are signposts of recent planet formation. Bright rings appear because dust associated with the formation of a…
Debris disks are dusty, gas-poor disks around main sequence stars (Backman & Paresce 1993; Lagrange, Backman & Artymowicz 2000; Zuckerman 2001). Micron-sized dust grains are inferred to exist in these systems from measurements of their…
Partial condensation of dust from the Solar nebula is likely responsible for the diverse chemical compositions of chondrites and rocky planets/planetesimals in the inner Solar system. We present a forward physical-chemical model of a…
Interstellar dust appears in a number of roles in the interstellar medium. Historically, the most familiar one is as a source of extinction in the optical. Absorbed optical and ultraviolet light heats the dust, whence infrared (including…
We report on five years of 3-5 micron photometry measurements obtained by warm Spitzer to track the dust debris emission in the terrestrial zone of HD 166191 in combination with simultaneous optical data. We show that the debris production…
Comets have been invoked in numerous studies as a potentially important source of dust and gas around stars, but none has studied the thermo-physical evolution, out-gassing rate, and dust ejection of these objects in such stellar systems.…
The study of gas-dust interactions occurring in the interstellar medium of a galaxy is essential for understanding various physical processes taking place within it. A comparison of such events at different locations corresponding to…