Rood-Sastry classification

Rood–Sastry classification

(rood shass -tree, sass -) A classification system for clusters of galaxies based on the nature and spatial distribution of the ten brightest galaxies in the cluster.

Rood-Sastry classification

[¦rüd ¦sas·trē ‚klas·ə·fə′kā·shən]
(astronomy)
A classification scheme for galaxy clusters that differentiates between a number of basic cluster morphologies.