Results 221 to 230 of about 50,798 (260)

Three-dimensional maps of the interstellar dust extinction curve within the Milky Way galaxy

Science
Interstellar dust grains cause extinction (absorption and scattering) of light from background astronomical sources. The spectral shape of the extinction curve depends on the dust composition. We used low-resolution optical spectra to measure the extinction curve of 130 million stars. By inverting these data, we mapped the extinction curve
Xiangyu Zhang, Gregory M. Green
openaire   +3 more sources

Infrared extinction of heavy ion irradiated and amorphous olivine, with applications to interstellar dust

Astrophysics and Space Science, 1979
A smooth surface layer of highly disordered olivine, (Mg, Fe)2SiO4, has been produced by exposure of polished, natural olivine to a dose of 5×1016 cm−2 of 1.5 MeV neon ions from a Van de Graaff accelerator. The dielectric functions of the disordered silicate in the wavelength range from 8 to 30 μm have been determined from analysis of specular ...
W. Kr�tschmer, Donald R. Huffman
openalex   +2 more sources

Light from cosmic dawn hints at how interstellar dust is made

Nature, 2023
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.
Xuejuan Yang, Aigen Li
semanticscholar   +1 more source

New Interstellar Extinction Maps Based on Gaia and Other Sky Surveys

Astronomy letters, 2023
We present new three-dimensional (3D) interstellar extinction maps in the \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek ...
G. Gontcharov, A. A. Marchuk, M. Khovrichev, A. Mosenkov, S. S. Savchenko, V. B. Il’in, D. M. Poliakov, A. A. Smirnov   +7 more
semanticscholar   +1 more source

Interstellar extinction by spheroidal absorbing dust grains

Astrophysics and Space Science, 1987
On the basis of exact computations of the extinction efficiencies of spheroidal absorbing particles, numerical calculations of the extinction curves have been made for a distribution of particle sizes. The results are presented and compared with the observed interstellar extinction. For the sake of comparison, results for the nonabsorbing particles are
D. B. Vaidya, J. N. Desai
openaire   +1 more source

Extinction and polarization of light by dust in the interstellar medium. Interstellar extinction curves

Astrophysics, 1986
A model of two-layer cylindrical interstellar dust grains is used to calculate the interstellar extinction curves in the visible and near infrared regions of the spectrum and the ratio R /sub V/ of the total to the selective extinction. It is assumed that the core of the two-layer grains consists of ''astronomical silicate'' and the mantle of dirty ice
N. V. Voshchinnikov, A. E. Il'in, V. B. Il'in   +2 more
openaire   +1 more source

Interstellar extinction and polarization by spheroidal dust grains

Astrophysics and Space Science, 1984
Using the recently available exact computations of the scattering efficiencies of spheroidal particles numerical calculations of the extinction and polarization curves have been made for a distribution of particle sizes, shapes and orientations. The results are presented and compared with the observed interstellar extinction and polarization.
D. B. Vaidya, H. C. Bhatt, J. N. Desai
openaire   +1 more source

Interstellar Dust Models: Extinction, Absorption and Emission

EAS Publications Series, 2009
The observational constraints on interstellar dust are summarized. A dust model, consisting of a mixture of amorphous silicate, graphite, and PAH material that reproduces the observed interstellar extinction, is described. It is used to calculate the infrared emission expected when such dust is heated by radiation with the spectrum of interstellar ...
openaire   +1 more source

Three-component dust models for interstellar extinction

Journal of Astrophysics and Astronomy, 2010
Interstellar extinction curves obtained from the ‘extinction without standard’ method were used to constrain the dust characteristics in the mean ISM (R V = 3.1), along the lines of sight through a high latitude diffuse molecular cloud towards HD 210121 (R
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Modeling of interstellar extinction with composite dust grains

Astronomical & Astrophysical Transactions, 2002
A model of interstellar dust must satisfy two conditions: dust grains have to be of the reasonable structure and chemical composition and explain basic observations. The latter are the interstellar extinction law and the depletion of interstellar elements. In this work, a new model of composite dust grains is considered.
openaire   +1 more source