What are the three primary classifications of galaxies based on visual appearance?
Answer
Spiral, Elliptical, and Irregular galaxies
Astronomers categorize galaxies primarily by their visual appearance into three distinct types. Spiral galaxies feature a rotating disk of stars and interstellar medium with a central bulge. Elliptical galaxies appear as ellipsoidal profiles, typically dominated by older stars with little interstellar gas. Irregular galaxies lack a distinct, symmetrical shape, often resulting from gravitational interactions or collisions with other systems.
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