NGC 5474 is a peculiar dwarf galaxy in the constellation Ursa Major. It is one of several companion galaxies of the Pinwheel Galaxy (M101), a grand-design spiral galaxy.[4][5] Among the Pinwheel Galaxy's companions, this galaxy is the closest to the Pinwheel Galaxy itself.[4] The gravitational interaction between NGC 5474 and the Pinwheel Galaxy has strongly distorted the former. As a result, the disk is offset relative to the nucleus.[4][6] The star formation in this galaxy (as traced by hydrogen spectral line emission) is also offset from the nucleus.[6] NGC 5474 shows some signs of a spiral structure. As a result, this galaxy is often classified as a dwarf spiral galaxy, a relatively rare group of dwarf galaxies.

NGC 5474
Hubble image of NGC 5474.[1]
Observation data (J2000 epoch)
ConstellationUrsa Major[2]
Right ascension14h 05m 01.6s[3]
Declination+53° 39′ 44″[3]
Redshift273 ± 9 km/s[3]
Distance21.2 ± 2.2 Mly (6.5 ± 0.7 Mpc)[3]
Apparent magnitude (V)11.3[3]
Characteristics
TypeSA(s)cd pec[3]
Apparent size (V)4.8 × 4.3[3]
Other designations
UGC 9013,[3] PGC 50216[3]

See also

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References

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  1. ^ "A dwarf galaxy ravaged by grand design". Picture of the Week. ESA/Hubble. Retrieved 17 June 2014.
  2. ^ R. W. Sinnott, ed. (1988). The Complete New General Catalogue and Index Catalogue of Nebulae and Star Clusters by J. L. E. Dreyer. Sky Publishing Corporation and Cambridge University Press. ISBN 978-0-933346-51-2.
  3. ^ a b c d e f g h i "NASA/IPAC Extragalactic Database". Results for NGC 5474. Retrieved 2006-09-20.
  4. ^ a b c Drozdovsky, I. O.; Karachentsev, I. D. (2000). "Photometric distances to six bright resolved galaxies". Astronomy and Astrophysics Supplement. 142 (3): 425–432. Bibcode:2000A&AS..142..425D. doi:10.1051/aas:2000155.
  5. ^ A. Sandage; J. Bedke (1994). Carnegie Atlas of Galaxies. Washington, D.C.: Carnegie Institution of Washington. ISBN 978-0-87279-667-6.
  6. ^ a b R. M. Gonzalez Delgado; E. Perez; C. Tadhunter; J. M. Vilchez; J. M. Rodriguez-Espinosa (2000). "H II Region Population in a Sample of Nearby Galaxies with Nuclear Activity. I. Data and General Results". Astrophysical Journal Supplement. 108 (1): 155. Bibcode:1997ApJS..108..155G. doi:10.1086/312951.
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