相关论文: Interstellar Grains: 50 Years On
This review provides an introduction to presolar grains - preserved stardust from the interstellar molecular cloud from which our solar system formed - found in primitive meteorites. We describe the search for the presolar components, the…
Identification by the Ulysses spacecraft of interstellar grains inside the planetary system provides a new window for the study of diffuse interstellar matter. Dust particles observed by Ulysses and confirmed by Galileo are more massive…
Galaxies represent the visible fabric of the Universe and there has been considerable progress recently in both observational and theoretical studies. The underlying goal is to understand the present-day diversity of galaxy forms, masses…
Substantial progress in the field of the Local Interstellar Medium has been largely due to recent launches of space missions, mostly in the UV and X-ray domains, but also to ground-based observations, mainly in high resolution spectroscopy.…
The abundant forms in which the major elements in the universe exist have been determined from numerous astronomical observations and meteoritic analyses. Iron (Fe) is an exception, in that only depletion of gaseous Fe has been detected in…
The sizes of interstellar grains are widely distributed, ranging from a few angstroms to a few micrometers. The ultraviolet (UV) and optical extinction constrains the dust in the size range of a couple hundredth micrometers to several…
We calculate and discuss the chemical evolution of the isotopic silicon abundances in the interstellar medium at distances and times appropriate to the birth of the solar system. This has several objectives, some of which are related to…
We study the effects of using the optical properties of irregular hexahedral grains in photoionization models of circumstellar nebulae around evolved stars. Dust opacities for the irregular grains were obtained from the scattering…
The X-ray regime is a largely underused resource for constraining interstellar dust grain models and improving our understanding of the physical processes that dictate how grains evolve over their lifetimes. This is mostly due to current…
In the interstellar medium of the Milky Way, certain elements -- e.g., Mg, Si, Al, Ca, Ti, Fe -- reside predominantly in interstellar dust grains. These grains absorb, scatter, and emit electromagnetic radiation, heat the interstellar…
We present the conceptual and technical background required to describe and understand the correlations and fluctuations of the empirical density and current of steady-state diffusion processes on all time scales -- observables central to…
The motion of diamagnetic dust particles in interstellar magnetic fields is studied numerically with several different sets of parameters. Two types of behavior are observed, depending on the value of the critical number $R$, which is a…
Grain growth is a ubiquitous and fundamental phenomenon observed in the cellular structures with the grain assembly separated by a network of grain boundaries, including metals and ceramics. However, the underlying mechanism of grain growth…
It is generally agreed that interstellar dust grains consist of two main components, namely, silicates and graphites. Some models, like MRN model, assume these grains to be homogeneous spheres following a power law size distribution. This…
Granular materials are involved in most industrial and environmental processes, as well as many civil engineering applications. Although significant advances have been made in understanding the statics and dynamics of cohesionless grains…
Interstellar dust is a key physical ingredient of galaxies, obscuring star formation, regulating the heating and cooling of the gas, and building-up chemical complexity. In this manuscript, I give a wide review of interstellar dust…
Stars are not smooth. Their photosphere is covered by a granulation pattern associated with the heat transport by convection. The convection-related surface structures have different size, depth, and temporal variations with respect to the…
Our current understanding of the absorption and emission properties of interstellar grains are reviewed. The constraints placed by the Kramers-Kronig relation on the wavelength-dependence and the maximum allowable quantity of the dust…
Searching for extrasolar biosignatures is important to understand life on Earth and its origin. Astronomical observations of exoplanets may find such signatures, but it is difficult and may be impossible to claim unambiguous detection of…
We summarize the current observational status of the interstellar medium in terms of the McKee/Ostriker model. We find both agreement and disagreement---hence the title of the paper. Some of the newest observations differ from older ones,…