Whirlpool galaxy

(Redirected from Messier 51)

The Whirlpool Galaxy, is also known as Messier 51a, M51a, or NGC 5194. It is a large galaxy with well-defined spiral arms, with a smaller companion galaxy. They have been through a collision,[7] and are still interacting.[6]

Whirlpool Galaxy
Messier51 sRGB.jpg
Whirlpool Galaxy (M51A or NGC 5194). The smaller object in the upper right is M51B or NGC 5195. Credit: NASA/ESA
Observation data (J2000 epoch)
ConstellationCanes Venatici[1]
Right ascension13h 29m 52.7s[2]
Declination+47° 11′ 43″[2]
Redshift463 ± 3 km/s[2]
Distance23 ± 4 Mly (7.1 ± 1.2 Mpc)[3][4]
TypeSA(s)bc pec[2]
Apparent dimensions (V)11′.2 × 6′.9[2]
Apparent magnitude (V)8.4[5]
Notable featuresInteracting with NGC 5195[6]
Other designations
Question Mark Galaxy,[2] Rosse's Galaxy,[2] M51a,[2] NGC 5194,[2] UGC 8493,[2] PGC 47404,[2] VV 001a,[2] VV 403,[2] Arp 85,[2] GC 3572[2]
See also: Galaxy, List of galaxies

The Whirlpool was the first galaxy to be classified as a spiral galaxy.[8] Different methods put its distance as between 15 to 35 million light-years. Recently it was estimated to be 23 ± 4 million light-years from the Milky Way.[3] Messier 51 is one of the best known galaxies in the sky.[9]

Its spiral arms are so impressive and well-defined that it is called a "grand design" spiral galaxy.[10] It has an active galactic nucleus,[11] no doubt fuelled by a massive black hole.

The galaxy and its companion, NGC 5195, are easily seen by amateur astronomers, in the constellation Canes Venatici. The two galaxies can be seen with binoculars.[12] The Whirlpool Galaxy is also a popular target for professional astronomers. They study its galaxy structure (particularly the spiral arms) and galaxy interactions.

Whirlpool Galaxy Media

Related pages

References

  1. ↑ Dreyer J.L.E. 1988. The Complete New General Catalogue and Index Catalogue of Nebulae and Star Clusters (1988)Sky Publishing Corporation/Cambridge University Press. ISBN 0-933346-51-4.
  2. ↑ 2.00 2.01 2.02 2.03 2.04 2.05 2.06 2.07 2.08 2.09 2.10 2.11 2.12 2.13 2.14 NASA/IPAC Extragalactic Database. Results for NGC 5194. Retrieved 2006-12-06.
  3. ↑ 3.0 3.1 Takáts K. & Vinkó J. 2006.. Distance estimate and progenitor characteristics of SN 2005cs in M51. Monthly Notices of the Royal Astronomical Society 372 (4) (2006). p. 1735–1740. doi:10.1111/j.1365-2966.2006.10974.x.
  4. ↑ Distance Results for MESSIER 051. NASA/IPAC Extragalactic Database. Retrieved 2011-06-06.
  5. ↑ M51SEDS.org.
  6. ↑ 6.0 6.1 Arp H. 1966 Atlas of peculiar galaxies. Astrophysical Journal Supplement 14, 1–20. [1]
  7. ↑ When galaxies collide, they actually move through each other. This causes gravitational effects, and leads to an increase in star formation.
  8. ↑ Whirlpool Galaxy: First Spiral Galaxy. Universe for Facts. Retrieved 21 December 2014.
  9. ↑ Scalzi, John 2003.. The Rough Guide to the Universe (2003)Rough Guides. p. 250. ISBN 1-85828-939-4.
  10. ↑ Elmegreen D.M. & Elmegreen B.G. 1987. Arm classifications for spiral galaxies. Astrophysical Journal 314 (1987). p. 3–9. doi:10.1086/165034.
  11. ↑ Matsushita, Satoki; Muller, Sebastien & Lim, Jeremy 2007. Jet-disturbed molecular gas near the Seyfert 2 nucleus in M51. Astronomy & Astrophysics 468 (A&A Letters Special Issue) (2007). p. L49–L52. doi:10.1051/0004-6361:20067039.
  12. ↑ Nemiroff, Robert & Bonnell, Jerry 2000. M51: The Whirlpool Galaxy. Astronomy Picture of the DayNASA. Retrieved 2007-04-22.