Sa galaxy

astronomy

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Last updated

July 15, 2026

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Sa galaxies are a type of normal spiral galaxy characterized by narrow, tightly wound arms. These arms are often visible due to interstellar dust and bright stars. Most Sa galaxies have a large central bulge, though some have a smaller nucleus with arms that are faint and arranged on a smooth disk. The classification of galaxies, including Sa types, originated with Edwin Hubble and was later revised by Allan Sandage. The Milky Way Galaxy is a typical large spiral system, featuring components like a nucleus, disk, and spiral arms. NGC 1302 is an example of an Sa galaxy.123

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Sa galaxies
These normal spirals have narrow, tightly wound arms, which usually are visible because of the presence of interstellar dust and, in many cases, bright stars. Most of them have a large amorphous bulge in the centre, but there are some that violate this…
Read More
These normal spirals have narrow, tightly wound arms, which usually are visible because of the presence of interstellar dust and, in many cases, bright stars. Most of them have a large amorphous bulge in the centre, but there are some that violate this…
Read More