A dwarf spiral galaxy is the dwarf version of a

spiral galaxy Spiral galaxies form a galaxy morphological classification, class of galaxy originally described by Edwin Hubble in his 1936 work ''The Realm of the Nebulae''

. Dwarf galaxies are characterized as having low luminosities, small diameters (less than 5 kpc), low surface brightnesses, and low

hydrogen Hydrogen is a chemical element; it has chemical symbol, symbol H and atomic number 1. It is the lightest and abundance of the chemical elements, most abundant chemical element in the universe, constituting about 75% of all baryon, normal matter ...

masses. The galaxies may be considered a subclass of low-surface-brightness galaxies. Dwarf spiral galaxies, particularly the dwarf counterparts of Sa–Sc type spiral galaxies, are quite rare. In contrast,

dwarf elliptical galaxies Dwarf elliptical galaxies (dEs) are elliptical galaxy, elliptical galaxies that are smaller than ordinary elliptical galaxy, galaxies. They are quite common in galaxy groups and galaxy cluster, clusters, and are usually companions to other galaxi ...

, dwarf irregular galaxies, and the dwarf versions of Magellanic type galaxies (which may be considered transitory between spiral and irregular in terms of morphology) are very common. It is suggested that dwarf spiral galaxies can transform into dwarf elliptical galaxies, especially in dense cluster environments.

Examples

* NGC 5474 * NGC 3928 * NGC 625 * NGC 1051 *

NGC 1311 NGC may refer to: Companies * NGC Corporation, the name of US electric company Dynegy, Inc. from 1995 to 1998 * National Gas Company of Trinidad and Tobago, a state-owned natural gas company in Trinidad and Tobago * National Grid plc, a former n ...

* NGC 5949

Location

Most identified dwarf spiral galaxies are located outside clusters. Strong gravitational interactions between galaxies and interactions between galaxies and intracluster gas are expected to destroy the disks of most dwarf spiral galaxies. Nonetheless, dwarf galaxies with spiral-like structure have been identified within the Virgo Cluster and Coma Cluster.

References

{{Portal bar, Stars, Outer space * * * Galaxy morphological types cs:Spirálová galaxie