To be published in Planets, Stars, and Stellar Systems, Vol. 6, Series Editor T. D. Oswalt, Volume editor W. C. Keel, Springer Reference, 2011

For a PDF version of the article, click here.


Ronald J. Buta

Department of Physics and Astronomy, University of Alabama, Box 870324, Tuscaloosa, AL 35487

Abstract: Galaxy morphology is a product of how galaxies formed, how they interacted with their environment, how they were influenced by internal perturbations, AGN, and dark matter, and of their varied star formation histories. This article reviews the phenomenology of galaxy morphology and classification with a view to delineating as many types as possible and how they relate to physical interpretations. The old classification systems are refined, and new types introduced, as the explosion in available morphological data has modified our views on the structure and evolution of galaxies.

Subject headings: galaxies: spiral; galaxies: elliptical; galaxies: S0s; galaxies: structure; galaxies: high redshift; galaxies: classification; galaxies: peculiar; galaxies: dwarfs; galaxies: clusters; galaxies: active; galaxies: isolated; galaxies: Galaxy Zoo project

Index terms: Hubble-Sandage-de Vaucouleurs classification; spiral galaxies; elliptical galaxies; S0 galaxies; irregular galaxies; resonance ring galaxies; outer rings; inner rings; nuclear rings; secondary bars; nuclear bars; pseudorings; grand design spirals; flocculent spirals; merger morphologies; tidal tails; collisional ring galaxies; polar ring galaxies; barred galaxies; lens galaxies; spiral arm classes; counter-winding spiral galaxies; anemic spiral galaxies; spiral arm multiplicity; dust lanes; pseudobulges; classical bulges; dust-lane elliptical galaxies; shell/ripple galaxies; ultra-luminous infrared galaxies; bar ansae; brightest cluster members; low surface brightness galaxies; dwarf galaxies; dwarf spiral galaxies; dwarf spheroidal galaxies; Galaxy Zoo project; isolated galaxies; blue compact dwarf galaxies; star-forming galaxy morphologies; warped disks; stellar mass morphology; luminosity classes; boxy ellipticals; disky ellipticals; late-type galaxies; early-type galaxies; Magellanic barred galaxies; color galaxy morphology; atomic and molecular gas galaxy morphology

Table of Contents