barred spiral galaxy

astronomy

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June 22, 2026

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A barred spiral galaxy is a type of spiral galaxy characterized by a luminous bar-shaped structure that extends across its nucleus. The spiral arms of these galaxies appear to originate from the ends of this bar.12

These galaxies are classified under the broader category of spiral galaxies, which also include normal spirals. Both types possess a central nucleus surrounded by a disk and spiral arms. However, in barred spirals, the arms unwind from the extremities of the bar, rather than directly from the nucleus as in normal spirals. The subclasses of barred spirals (SB) parallel those of normal spirals (S), with further distinctions based on the size of the nucleus and the tightness of the spiral arms.23

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SB galaxies
…spectra, and distributions of the barred spirals tend to be indistinguishable from those of normal spirals. The subclasses of SB systems exist in parallel sequence to those of the latter.
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…spectra, and distributions of the barred spirals tend to be indistinguishable from those of normal spirals. The subclasses of SB systems exist in parallel sequence to those of the latter.
Read More