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Density and Velocity Distribution of the Interstellar Gas

Published online by Cambridge University Press:  03 August 2017

H. C. van de Hulst
H. C. van de Hulst*
Affiliation:
Leiden Observatory, Leiden, The Netherlands

Extract

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The interstellar gas shows wide variations in density and in velocity. Common words to describe the existence of these variations are cloudiness for the density and turbulence for the velocity field. These terms have initially been introduced as vague descriptions and were not based on mathematical analysis or dynamical theory. The word cloud as used by astronomers did not always mean a region of large density with relatively sharp boundaries; nor did the word turbulence necessarily imply a velocity field with well-defined statistical regularities and energy dissipation by means of viscosity.

Type
Part I: Empirical Studies of Velocity Fields in, and Related Structure of, the Interstellar Medium
Information
Symposium - International Astronomical Union , Volume 8: Cosmical Gas Dynamics , July 1958 , pp. 913 - 923
Copyright
Copyright © American Physical Society 1958 

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