Astronomy:Flocculent spiral galaxy

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Short description: Patchy galaxy with discontinuous spiral arms
NGC 2775, a prominent flocculent spiral galaxy

A flocculent spiral galaxy is a type of spiral galaxy. Unlike the well-defined spiral architecture of a grand design spiral galaxy, flocculent (meaning "flaky") galaxies are patchy, with discontinuous spiral arms.[1][2] Self-propagating star formation is the apparent explanation for the structure of flocculent spirals.[3] Approximately 30% of spirals are flocculent, 10% are grand design, and the rest are referred to as "multi-armed".[4] The multiple-arm type is sometimes grouped into the flocculent category.[5]

The prototypical flocculent spiral is NGC 2841.[6]

List of flocculent spiral galaxies

Example Class Image Constellation Notes
NGC 1325 SBbc NGC 1325 -HST09042 18-R814GB450.png Eridanus
NGC 1353 SBb NGC 1353 -HST06359 49-606.png Eridanus
NGC 2775 SA(r)ab Birds of a feather (50071190086).jpg Cancer [7]
NGC 2841 SA(r)b NGC 2841.jpg Ursa Major [6]
NGC 3521 SAB(r s)bc NGC3521-eso1129a.jpg Leo [6]
NGC 4298 SA(r s)c NGC 4298 cropped.jpg Coma Berenices
NGC 4414 SA(r s)c NGC 4414 (NASA-med).jpg Coma Berenices [8]
NGC 7793 SA(s)d Phot-14b-09-fullres 2.JPG Sculptor [6]
Sunflower Galaxy
(Messier 63)
SAB(r s)cd M63 (NGC 5055).jpg Canes Venatici [9]

References

  1. COSMOS – SAO Encyclopedia of Astronomy, "Grand Design Spiral" (Retrieved 23 April 2010)
  2. COSMOS – SAO Encyclopedia of Astronomy, "Flocculent Spiral" (Retrieved 23 April 2010)
  3. Masters, Karen (September 2002), What is the Origin of Spiral Structure in Galaxies, http://curious.astro.cornell.edu/question.php?number=199, retrieved 2007-05-30 
  4. Case Western Reserve University, Chris Mihos, ASTR222 – Spring 2008, "Spiral Structure" (Retrieved 23 April 2010)
  5. University of Virginia, Mark Whittle, ASTR 553/554 : Extragalactic Astronomy (2007), "Lecture 5: Spiral Galaxies" (Retrieved 23 April 2010)
  6. 6.0 6.1 6.2 6.3 "A Near-Infrared Atlas of Spiral Galaxies", Debra Meloy Elmegreen, "CH3. Discussion" (Retrieved 23 April 2010)
  7. "Hubble Spots Feathered Spiral". NASA. 2 July 2020. https://www.nasa.gov/image-feature/goddard/2020/hubble-spots-feathered-spiral. 
  8. Nemiroff, R.; Bonnell, J., eds (3 April 2002). "NGC 4414: A Flocculent Spiral Galaxy". Astronomy Picture of the Day. NASA. https://apod.nasa.gov/apod/ap020403.html. 
  9. NASA (2015). [1]. Retrieved 2 March 2017

Sources

External links