相关论文: Organic Matter in Space - an Overview
Extensive photometric stellar surveys show that many main sequence stars show emission at infrared and longer wavelengths that is in excess of the stellar photosphere; this emission is thought to arise from circumstellar dust. The presence…
We draw attention to observational evidence indicating that a substantial fraction of the well-known cosmic celestial diffuse ultraviolet background radiation field is actually due not to dust-scattered starlight, but rather---considering…
The horizon for studies of element abundances has expanded dramatically in the last ten years. Once the domain of astronomers concerned chiefly with stars and nearby galaxies, this field has now become a key component of observational…
The obscuration of light from a distant galaxy has raised the possibility that a type of carbon dust existed in the earliest epochs of the Universe -- challenging the idea that stars had not yet evolved enough to make such material.
Ultraviolet spectra of stars recorded by orbiting observatories since the 1970's have revealed absorption features produced by atoms in their favored ionization stages in the neutral ISM of our Galaxy. Most elements show abundances relative…
The ultraviolet and optical background forms a baseline for any observation of the sky. It includes emission lines and scattered light from the atmosphere; resonant scattering from the Lyman lines of interplanetary hydrogen and the…
How does molecular complexity emerge and evolve during the process leading to the formation of a planetary system? Astrochemistry is experiencing a golden age, marked by significant advancements in the observation and understanding of the…
Interstellar dust is a significant component of matter in the galaxies. The dust owns its origin and reprocessing in a wide range of astrophysical environments. In order to understand the origin and evolution of the distinct types of…
Presence of dust in galaxies removes half or more of the stellar energy from the UV-optical budget of the Universe and has profound impact on our understanding of how galaxies evolve. Measures of opacity in local galaxies are reviewed…
The origin of complex organic molecules such as amino acids and their precursors found in meteorites and comets is unknown. Previous studies have accounted for the complex organic inventory of the Solar System by aqueous chemistry on warm…
In this chapter, we explore the origins of cometary material and discuss the clues cometary composition provides in the context of the origin of our solar system. The review focuses on both cometary refractory and volatile materials, which…
There is a long-standing discussion in the astrophysical/astrochemical community as to the structure and morphology of dust grains in various astrophysical environments (e.g., interstellar clouds, protostellar envelopes, protoplanetary and…
Composite particles---atoms, molecules, or microspheres---are unique tools for testing joint quantum and general relativistic effects, macroscopic limits of quantum mechanics, and searching for new physics. However, all studies of the free…
Protoplanetary disks are dynamic objects, within which dust grains and gas are expected to be redistributed over large distances. Evidence for this redistribution is seen both in other protoplanetary disks and in our own Solar System, with…
This comprehensive review summarizes our current understanding of the evolution of gas, solids and molecular ices in protoplanetary disks. Key findings related to disk physics and chemistry, both observationally and theoretically, are…
Circumstellar disks are an integral part of the star formation process and the sites where planets are formed. Understanding the physical processes that drive their evolution, as disks evolve from optically thick to optically thin, is…
There remain many open questions relating to the depletion of elements into dust, e.g., exactly how are C and O incorporated into dust in dense clouds and, in particular, what drives the disappearance of oxygen in the denser interstellar…
Planets form in disks of gas and dust around young stars. The disk molecular reservoirs and their chemical evolution affect all aspects of planet formation, from the coagulation of dust grains into pebbles, to the elemental and molecular…
Observations of exoplanet atmospheres have shown that aerosols, like in the Solar System, are common across a variety of temperatures and planet types. The formation and distribution of these aerosols are inextricably intertwined with the…
Debris disks are optically thin, almost gas-free dusty disks observed around a significant fraction of main-sequence stars older than about 10 Myr. Since the circumstellar dust is short-lived, the very existence of these disks is considered…