normal spiral galaxy

astronomy

Also known as: ordinary spiral galaxy

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Last updated

July 1, 2026

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A normal spiral galaxy is characterized by a bright nucleus surrounded by a thin outer disk and a superimposed spiral structure. These galaxies have arms that emanate from the nucleus. Both the arms and the disk of a spiral system appear blue, while their central areas are red. The Milky Way Galaxy is a typical example of a large spiral system, featuring a nucleus, central bulge, disk, spiral arms, a spherical component, and a massive halo. The spiral arms themselves often follow a logarithmic spiral form.1234567

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galaxy
Spiral galaxies
…divided into two parallel classes: normal spirals and barred spirals. The normal spirals have arms that emanate from the nucleus, while barred spirals have a bright linear feature called a bar that straddles the nucleus, with the arms unwinding from the ends of the bar. The nucleus of a spiral…
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…divided into two parallel classes: normal spirals and barred spirals. The normal spirals have arms that emanate from the nucleus, while barred spirals have a bright linear feature called a bar that straddles the nucleus, with the arms unwinding from the ends of the bar. The nucleus of a spiral…
Read More