Sb galaxy
Quick Summary
Sb galaxies are a type of spiral galaxy characterized by a nucleus surrounded by a disk and spiral arms. They are a subclass of barred spirals (SB), distinguished by a linear feature called a bar that straddles the nucleus, with arms unwinding from its ends.12
Sb galaxies typically have a medium-sized nucleus and arms that are more widely spread than those of Sa types, appearing less smooth and containing stars, gas, and dust. While theoretical models can reproduce the basic Sb shape, many observed variations in their structure remain unexplained. The Andromeda Galaxy is a well-known example of an Sb galaxy.1
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