Messier 74 (also known as NGC 628 and Phantom Galaxy) is a large spiral galaxy in the equatorial constellation Pisces.[a] It is about 32 million light-years away from Earth.[6] The galaxy contains two clearly defined spiral arms and is therefore used as an archetypal example of a grand design spiral galaxy.[7] The galaxy's low surface brightness makes it the most difficult Messier object for amateur astronomers to observe.[8][9] Its relatively large angular (that is, apparent) size and the galaxy's face-on orientation make it an ideal object for professional astronomers who want to study spiral arm structure and spiral density waves. It is estimated that M74 hosts about 100 billion stars.[6]

Messier 74
The spiral galaxy M74 (in the left bottom corner is the supernova SN 2013ej)
Observation data (J2000 epoch)
ConstellationPisces[1]
Right ascension01h 36m 41.8s[2]
Declination+15° 47′ 01″[2]
Redshift657 km/s[2]
Distance30 ± 6 Mly[3]
Apparent magnitude (V)9.4[4]
Characteristics
TypeSA(s)c[2]
Number of stars100 billion (1×1011)
Size95,000 ly (diameter)[5]
Apparent size (V)10′.5 × 9′.5[2]
Other designations
NGC 628, UGC 1149, PGC 5974[2]

Observation history edit

M74 was discovered by Pierre Méchain in 1780. He then communicated his discovery to Charles Messier, who listed the galaxy in his catalog.[9]

 
M74 observed by JWST

In July 2022, it was observed by the James Webb Space Telescope.

Structure edit

M74 has two spiral arms that wind counterclockwise from the galaxy's center. The spiral arms widen as they get farther from M74's center, but one of the arms narrows at the end. The arms deviate slightly from a constant angle.[10]

Supernovae edit

Three supernovae are known to have taken place within it:[2] SN 2002ap,[11] SN 2003gd,[12] and SN 2013ej (the numbers denote the year).[13] The latter was bright as 10th magnitude when viewed from the surface of Earth, so visible from almost all modern telescopes in a good night sky.[13]

SN 2002ap was one of few Type Ic supernovae (which denotes hypernovae) recorded within 10 Mpc every century.[14][15][16] This explosion has been used to test theories on the origins of others further away[15] and theories on the emission by supernovae of gamma ray bursts.[16]

SN 2003gd is a Type II-P supernova.[17] Type II supernovae have known luminosities, so they can be used to accurately measure distances. The distance measured to M74 using SN 2003gd is 9.6 ± 2.8 Mpc, or 31 ± 9 million ly.[3] For comparison, distances measured using the brightest supergiants are 7.7 ± 1.7 Mpc and 9.6 ± 2.2 Mpc.[3] Ben Sugerman found a "light echo" – a later reflection of the explosion – associated with SN 2003gd.[18] This is one of the few supernovae in which such a reflection has been found. This reflection appears to be from dust in a sheet-like cloud that lies in front of the supernova, and it can be used to determine the composition of the interstellar dust.[18][19]

Galaxy group edit

This is the brightest member of the M74 Group, a group of 5 to 7 galaxies that also includes the peculiar spiral galaxy NGC 660 and a few irregular galaxies.[20][21][22] Different group membership identification methods (ranging from a clear, to likely, to perhaps historic gravitational tie) identify several objects of the group in common,[22] and a few galaxies whose exact status within such groupings is currently uncertain.[22]

 
M74 as observed with the Spitzer Space Telescope as part of the Spitzer Infrared Nearby Galaxy Survey. The blue colors represent the 3.6 micrometre emission from stars. The green and red colors represent the 5.8 and 8.0 micrometre emission from polycyclic aromatic hydrocarbons and possibly dust.

Suspected black hole edit

In 2005[23][b] the Chandra X-ray Observatory announced its observation of an ultraluminous X-ray source (ULX) in M74, radiating more X-ray power than a neutron star, in periodic intervals of around two hours. It has an estimated mass of 10000 M. This is an indicator of an intermediate-mass black hole. This would be a rather uncommon class, in between in size of stellar black holes and the massive black holes theorized to be in the center of many galaxies. Such an object is believed to form from lesser ("stellar") black holes within a star cluster. The source has been given identification number CXOU J013651.1+154547.

Amateur astronomy observation edit

Messier 74 is 1.5° east-northeast of Eta Piscium.[8][9] This galaxy has the second-lowest Earth-surface brightness of any Messier object. (M101 has the lowest.) It requires a good night sky.[9] [8] This galaxy may be best viewed under low magnification; when highly magnified, the diffuse emission becomes more extended and appears too faint to be seen by many people.[9] Additionally, M74 may be more easily seen when using averted vision when the eyes are fully dark adapted.[8][9]

See also edit

References and footnotes edit

  1. ^ 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 / Cambridge University Press. ISBN 978-0-933346-51-2.
  2. ^ a b c d e f g "NASA/IPAC Extragalactic Database". Results for NGC 628. Retrieved 2006-08-12.
  3. ^ a b c M. A. Hendry; S. J. Smartt; J. R. Maund; A. Pastorello; L. Zampieri; S. Benetti; et al. (2005). "A study of the Type II-P supernova 2003gd in M74". Monthly Notices of the Royal Astronomical Society. 359 (3): 906–926. arXiv:astro-ph/0501341. Bibcode:2005MNRAS.359..906H. doi:10.1111/j.1365-2966.2005.08928.x. S2CID 119479585.
  4. ^ "Messier 74". SEDS Messier Catalog. Archived from the original on 27 June 2023. Retrieved 30 April 2022.
  5. ^ "Messier Object 74".
  6. ^ a b Nemiroff, R.; Bonnell, J., eds. (2011-04-06). "M74: The Perfect Spiral". Astronomy Picture of the Day. NASA. Retrieved 2011-04-07.
  7. ^ A. Sandage; J. Bedke (1994). Carnegie Atlas of Galaxies. Carnegie Institution of Washington. ISBN 978-0-87279-667-6.
  8. ^ a b c d S. J. O'Meara (1998). The Messier Objects. Cambridge University Press. ISBN 978-0-521-55332-2.
  9. ^ a b c d e f K. G. Jones (1991). Messier's Nebulae and Star Clusters (2nd ed.). Cambridge: Cambridge University Press. ISBN 978-0-521-37079-0.
  10. ^ Honig, Z.N.; Reid, M.J. (February 2015). "Characteristics of Spiral Arms in Late-type Galaxies". The Astrophysical Journal. 800 (1): 5387–5394. arXiv:1412.1012. Bibcode:2015ApJ...800...53H. doi:10.1088/0004-637X/800/1/53. PMID 53. S2CID 118666575. Retrieved November 10, 2022.
  11. ^ Nakano, S.; Hirose, Y.; Kushida, R.; Kushida, Y.; Li, W. (2002). "Supernova 2002ap in M74". IAU Circular. 7810: 1. Bibcode:2002IAUC.7810....1N.
  12. ^ R. Evans; R. H. McNaught (2003). "Supernova 2003gd in M74". IAU Circular. 8150: 2. Bibcode:2003IAUC.8150....2E.
  13. ^ a b "Bright supernova in M74". Sky & Telescope. 2013-07-29. Retrieved 2019-11-22.
  14. ^ P. A. Mazzali; J. Deng; K. Maeda; K. Nomoto; H. Umeda; K. hatano; et al. (2002). "The Type Ic Hypernova SN 2002ap". Astrophysical Journal. 572 (1): L61–L65. Bibcode:2002ApJ...572L..61M. doi:10.1086/341504.
  15. ^ a b S. J. Smartt; P. M. Vreeswijk; E. Ramirez-Ruiz; G. F. Gilmore; W. P. S. Meikle; A. M. N. Ferguson; et al. (2002). "On the Progenitor of the Type Ic Supernova 2002ap". Astrophysical Journal. 572 (2): L147–L151. arXiv:astro-ph/0205241. Bibcode:2002ApJ...572L.147S. doi:10.1086/341747. S2CID 2130591.
  16. ^ a b A. Gal-Yam; E. O. Ofek; O. Shemmer (2002). "Supernova 2002ap: The first month". Monthly Notices of the Royal Astronomical Society Letters. 332 (4): L73–L77. arXiv:astro-ph/0204008. Bibcode:2002MNRAS.332L..73G. doi:10.1046/j.1365-8711.2002.05535.x. S2CID 119332396.
  17. ^ S. D. Van Dyk; W. Li; A. V. Filippenko (2003). "On the Progenitor of the Type II-Plateau Supernova 2003gd in M74". Publications of the Astronomical Society of the Pacific. 115 (813): 1289–1295. arXiv:astro-ph/0307226. Bibcode:2003PASP..115.1289V. doi:10.1086/378308. S2CID 119521479.
  18. ^ a b B. E. K. Sugerman (2005). "Discovery of a Light Echo from SN 2003gd". Astrophysical Journal Letters. 632 (1): L17–L20. arXiv:astro-ph/0509009. Bibcode:2005ApJ...632L..17S. doi:10.1086/497578. S2CID 11853657.
  19. ^ S. D. Van Dyk; W. Li; A. V. Filippenko (2006). "The Light Echo around Supernova 2003gd in Messier 74". Publications of the Astronomical Society of the Pacific. 118 (841): 351–357. arXiv:astro-ph/0508684. Bibcode:2006PASP..118..351V. doi:10.1086/500225. S2CID 1852671.
  20. ^ R. B. Tully (1988). Nearby Galaxies Catalog. Cambridge University Press. ISBN 978-0-521-35299-4.
  21. ^ A. Garcia (1993). "General study of group membership. II – Determination of nearby groups". Astronomy and Astrophysics Supplement. 100: 47–90. Bibcode:1993A&AS..100...47G.
  22. ^ a b c G. Giuricin; C. Marinoni; L. Ceriani; A. Pisani (2000). "Nearby Optical Galaxies: Selection of the Sample and Identification of Groups". Astrophysical Journal. 543 (1): 178–194. arXiv:astro-ph/0001140. Bibcode:2000ApJ...543..178G. doi:10.1086/317070. S2CID 9618325.
  23. ^ Chandra : Photo Album and details of observation: M74 : 22 Mar 05
  1. ^ Its very mild northerly declination means it rises daily (above the horizon) at latitudes above the 75th parallel south
  2. ^ On March 22

External links edit