spiral galaxy
Spiral galaxies form a class of galaxy originally described by Edwin Hubble in his 1936 work ''The Realm of the Nebulae''grand design spiral galaxy
A grand design spiral galaxy is a type of spiral galaxy with prominent and well-defined spiral arms, as opposed to multi-arm and flocculent spirals which have subtler structural features. The spiral arms of a grand design galaxy extend clearly a ...
, flocculent (meaning "flaky") galaxies are patchy, with discontinuous
spiral arm
Spiral galaxies form a class of galaxy originally described by Edwin Hubble in his 1936 work ''The Realm of the Nebulae''Self-propagating star formation is the apparent explanation for the structure of flocculent spirals. Approximately 30% of spirals are flocculent, 10% are grand design, and the rest are referred to as "multi-armed". The multiple-arm type is sometimes grouped into the flocculent category.University of Virginia, Mark Whittle, ''ASTR 553/554 : Extragalactic Astronomy (2007)'', "Lecture 5: Spiral Galaxies" (accessed 23 April 2010)
The prototypical flocculent spiral is NGC 2841."A Near-Infrared Atlas of Spiral Galaxies", Debra Meloy Elmegreen "CH3. Discussion" (accessed 23 April 2010)
List of flocculent spiral galaxies
References
Sources
PDF ''A Near-Infrared Atlas of Spiral Galaxies'', Debra Meloy Elmegreen, 1981, ,