Results 191 to 200 of about 4,494 (233)

FRACTAL ASPECTS OF INTERSTELLAR CLOUDS

Fractals, 1993
Interstellar matter consisting of gas and dust shows structures which appear to have self-similar projected shapes, similar to the properties of terrestrial clouds. Moreover, the completely different physics in these interstellar clouds reveals several additional self-similar/fractal aspects which are investigated by extensive astronomical ...
Zimmermann, Thomas, Stutzki, Jürgen
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Masses of interstellar clouds

Astrophysics and Space Science, 1978
Equilibrium masses of slowly rotating interstellar gas clouds have been calculated using an equation of state for the interstellar gas developed by Penston and Brown. The rotation is found to increase the equilibrium masses, but still the cloud masses are not as large as indicated by other considerations.
A. N. Dharmani, V. B. Bhatia
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Molecules in Interstellar Clouds

1981
The physical and chemical state of interstellar clouds is reviewed, including recent investigations at the Onsala Space Observatory. The Orion A region is chosen as an example of a “giant” molecular cloud and hence a formation site for massive stars. The Taurus Molecular Clouds, in contrast, may be the future birthplace of solar-type stars.
Irvine, William M., Hjalmarson, Ake, Rydbeck, Olof   +2 more
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Interstellar and Atmospheric Clouds

Nature, 1970
WE wish to draw attention to a novel and striking similarity between the physics of two apparently quite disparate situations—the behaviour of the interstellar medium and of water vapour in an atmospheric cloud.
G. R. EVANS, M. V. PENSTON
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The Composition of Interstellar Molecular Clouds

Space Science Reviews, 1999
We consider four aspects of interstellar chemistry for comparison with comets: molecular abundances in general, relative abundances of isomers (specifically, HCN and HNC), ortho/para ratios for molecules, and isotopic fractionation, particularly for the ratio hydrogen/deuterium.
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Translucent Interstellar Clouds

2011
A translucent interstellar cloud is one that has visual extinction intermediate between that of a ▶ diffuse cloud and that of a dense ▶molecular cloud. Despite the importance of photochemical processes over much of their extent, translucent clouds contain significant molecular column densities.
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Thermal instability in magnetized interstellar clouds

Astronomical & Astrophysical Transactions, 1997
Abstract The effect of a magnetic field on the ionizational-thermal acoustic instability in the cold diffuse ISM is discussed in this paper. It is found that the frozen-in magnetic field leads to new types of instabilities called “magnetoacoustic” instabilities.
Alexander E. Dudorov, Constantine E. Stepanov   +1 more
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The chemical composition of interstellar molecular clouds

Origins of Life, 1984
The published version is located at http://www.springerlink.com/content/w327411847532321/
Irvine, William M., HJALMARSON, A
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Interstellar Cloud Chemistry Revisited

1987
My first encounter with interstellar cloud chemistry (Bates and Spitzer 1951) took place 35 years ago. The field then had a semblance of simplicity. Absorption lines in the spectra of a number of stars had revealed the existence of molecules in interstellar space.
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Dense Interstellar Cloud Chemistry

1988
Significant advances in our understanding of the gas phase chemistry of dense interstellar clouds have occurred in the last few years. These advances include the delineation of the reaction pathways by which complex molecules are produced, a preliminary understanding of the varied chemistries existing in and near regions of star formation, an ...
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