An Etymological Dictionary of Astronomy and Astrophysics

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فرهنگ ریشه‌شناختی اخترشناسی-اخترفیزیک

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crossing time
  زمان ِ گذر  
zamân-e gozar (#)
Fr.: temps de traversée  

A concept used for checking the stability of a group of mass such as a → cluster of galaxies or a → star cluster. The crossing time is given by tc = R/V, where R is the average projected radial distance of group members from the center of mass and V the Gaussian dispersion in internal velocity.

See also: → cross; → time.