also: うずじょうぎんが
spiral galaxy
Astronomical term for a galaxy with a spiral structure, such as the Milky Way. Synonymous with 渦巻銀河 (うずまきぎんが).
See also: 渦巻銀河
The Andromeda Galaxy is one of the spiral galaxies.
The spiral structure of spiral galaxies is formed by density waves in the interstellar medium.