Interstellar material around the Sun is typical for our neighborhood of the Galaxy. The physical properties and kinematics of the partially ionized interstellar material (ISM) near the Sun are typical of warm diffuse clouds in the solar vicinity. The direction of the interstellar magnetic field at the heliosphere, the polarization of light from nearby stars, and the kinematics of nearby clouds ...

The rapid time variability of gamma-ray bursts implies the sources are very compact, and the peak luminosities are so high that some matter must be ejected at ultra-relativistic speeds. The very large Lorentz factors of the bulk flow are also indicated by the very broad and hard spectra. It is natural to expect that when the relativistic ejecta interact with the interstellar matter a strong syn...

Chemo-dynamical models have been introduced in the late eighties and are a generally accepted tool for understanding galaxy evolution. They have been successfully applied to one-dimensional problems, e.g. the evolution of nonrotating galaxies, and two-dimensional problems, e.g. the evolution of disk galaxies. Recently, also three-dimensional chemo-dynamical models have become available. In thes...

In this paper Beckwith asks if DM and gravitons could also impact the cosmic acceleration of the universe, leading to an increase of acceleration one billion years ago, in a manner usually attributed to DE. Following Marcio E. S. Alves, Oswaldo D. Miranda, Jose C. N. de Araujo, 2009 Beckwith will high light what KK style gravitons, with a slightly different mass profile could mean in terms of h...

It is a great pleasure to attend this meeting in honor of a long-time friend, Frank Avignone, and dedicated to his favorite subject, neutrino physics. In contrast to the rare neutrino events that Frank has measured in the laboratory, I will talk about an environment where neutrino reactions are so frequent that they determine much of the chemistry of the matter. That environment is the progenit...

From the point of view of radiation safety, interstellar space is not empty. Neutral and ionized interstellar gas and cosmic rays consisting of H and He-nucleons constitute radiation hazard aboard relativistic interstellar ships. Relativistic aberration of cosmic rays is evaluated and radiation doses from oncoming relativistic flow of interstellar gas and cosmic rays are estimated. Necessary sh...

The past century of interstellar dust has brought us from first ignoring it to finding that it is an important component of the interstellar medium and plays an important role in the evolution of galaxies, the formation of stars and planetary systems, and possibly, the origins of life. Current observational results in our galaxy provide a complex physical and chemical evolutionary picture of in...

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 medium by photoelectric emission, play a role in the ionization balance of the gas, and catalyze the formation of molecules, particularly H2. I review the state of ...

The carrier of the 2175 Å interstellar extinction feature remains unidentified since its first detection over 40 yr ago. In recent years, carbon buckyonions have been proposed as a carrier of this feature, based on the close similarity between the electronic transition spectra of buckyonions and the 2175 Å interstellar feature. We examine this hypothesis by modelling the interstellar extinction...

Abstract A massive naked singularity would be cloaked by accreted matter, and thus may appear to a distant observer as an opaque (quasi-)spherical surface of fluid, not unlike that star or planet. We present here analytical solutions for levitating atmospheres around wide class spherically symmetric singularities. Such atmosphere can constructed in every spacetime which possesses zero-gravity r...