Sign on
ADS Classic is now deprecated. It will be completely retired in October 2019. This page will automatically redirect to the new ADS interface at that point.

SAO/NASA ADS Astronomy Abstract Service

· Find Similar Abstracts (with default settings below)
· Full Refereed Journal Article (PDF/Postscript)
· Full Refereed Scanned Article (GIF)
· References in the article
· Citations to the Article (45) (Citation History)
· Refereed Citations to the Article
· Associated Articles
· Also-Read Articles (Reads History)
· Translate This Page
The velocity dispersion of the giant molecular clouds - A viscous origin [ Erratum: 1989ApJ...337.1035J ]
Jog, Chanda J.; Ostriker, Jeremiah P.
AA(Princeton University Observatory, NJ; Virginia, University, Charlottesville), AB(Princeton University Observatory, NJ)
Astrophysical Journal, Part 1 (ISSN 0004-637X), vol. 328, May 15, 1988, p. 404-426. (ApJ Homepage)
Publication Date:
NASA/STI Keywords:
Hydrodynamics, Interstellar Gas, Milky Way Galaxy, Molecular Clouds, Velocity Distribution, Computational Astrophysics, Harmonic Oscillators, Kinetic Energy, Random Processes, Time Dependence
Bibliographic Code:


The authors propose the energy source and study the details of the acceleration mechanism for the random motion of the Giant Molecular Clouds (GMCs) in the Galaxy. Gravitational scattering of the massive clouds off each other in the differentially rotating galactic disk constitutes an effective "gravitational" viscosity, which causes an increase in the random kinetic energy of the GMCs at the expense of their ordered, rotational kinetic energy in the galactic disk. The authors calculate the rate of increase, due to this effect, of the random kinetic energy of a GMC with a nonzero initial random velocity. Locally the fraction of the rotational kinetic energy lost in supporting inelastic cloud motions for ≡10 billion years is small, ≡0.1. As a result of the viscous interaction among the clouds, the clouds drift inward. Thus, the dynamics as well as the radial distribution in the Galaxy of the GMCs is determined by their gravitational viscous interaction, which operates because of their location in the differentially rotating galactic disk.

Associated Articles

Main Paper     Erratum    

Printing Options

Print whole paper
Print Page(s) through

Return 600 dpi PDF to Acrobat/Browser. Different resolutions (200 or 600 dpi), formats (Postscript, PDF, etc), page sizes (US Letter, European A4, etc), and compression (gzip,compress,none) can be set through the Printing Preferences

More Article Retrieval Options

HELP for Article Retrieval

Bibtex entry for this abstract   Preferred format for this abstract (see Preferences)

Find Similar Abstracts:

Use: Authors
Keywords (in text query field)
Abstract Text
Return: Query Results Return    items starting with number
Query Form
Database: Astronomy
arXiv e-prints