barred Spiral

Definition

Astronomy

  • Type of spiral galaxy in which the spirals stem not from the centre of the galaxy but from a ‘bar’ of stars and other material. Since the bars in barred spirals can be either structurally dominant in the galaxy or almost invisible, barred and normal spirals seem to shade into each other rather than being two distinct species. Barred spirals are of type SBa, SBb or SBc according to the tightness of the spirals, a being the tightest.
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