Messier 77

Messier 77
Hubble Space Telescope image of M77
Observation data (J2000 epoch)
ConstellationCetus
Right ascension02h 42m 40.771s[1]
Declination−00° 00′ 47.84″[1]
Redshift1,137±3 km/s[2]
Distance47 Mly (14.4 Mpc)[3]
Apparent magnitude (V)8.9[4]
Characteristics
Type(R)SA(rs)b[5]
Mass~1×109[6] M☉
Size27.70 kiloparsecs (90,000 light-years)[2]
(diameter; D25 isophote)
Apparent size (V)7.1′ × 6.0′[2]
Notable featuresOne of the biggest galaxies of Messier's catalog. Inclination estimated to be 40°.[3]
Other designations
Cetus A, M77, NGC 1068, 3C 71, 4C -00.13, Arp 37, UGC 2188, PGC 10266[7]
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Messier 77 (M77), also known as NGC 1068 or the Squid Galaxy, is a barred spiral galaxy in the constellation Cetus. It is about 47 million light-years (14 Mpc) away from Earth, and was discovered by Pierre Méchain in 1780, who originally described it as a nebula. Méchain then communicated his discovery to Charles Messier, who subsequently listed the object in his catalog.[8] Both Messier and William Herschel described this galaxy as a star cluster.[8] Today, however, the object is known to be a galaxy. It is one of the brightest Seyfert galaxies visible from Earth and has a D25 isophotal diameter of about 27.70 kiloparsecs (90,000 light-years).[2]

The morphological classification of NGC 1068 in the De Vaucouleurs system is (R)SA(rs)b,[5] where the '(R)' indicates an outer ring-like structure, 'SA' denotes a non-barred spiral, '(rs)' means a transitional inner ring/spiral structure, and 'b' says the spiral arms are moderately wound.[9] Ann et al. (2015) gave it a class of SAa,[10] suggesting tightly wound arms. However, infrared images of the inner part of the galaxy reveal a prominent bar not seen in visual light,[11] and for this reason it is now considered a barred spiral.[12]

Messier 77 is an active galaxy with an active galactic nucleus (AGN), which is obscured from view by astronomical dust at visible wavelengths. The diameter of the molecular disk and hot plasma associated with the obscuring material was first measured at radio wavelengths by the VLBA and VLA. The hot dust around the nucleus was subsequently measured in the mid-infrared by the MIDI instrument at the VLTI. It is the brightest[13] and one of the closest and best-studied[12] type 2 Seyfert galaxies,[3] forming a prototype of this class.[12]

M77 Type II Supernova, November 2018

X-ray source 1H 0244+001 in Cetus has been identified as Messier 77.[14] Only one supernova has been detected in Messier 77. The supernova, named SN 2018ivc, was discovered on 24 November 2018 by the DLT40 Survey. It is a type II supernova, and at discovery it was 15th magnitude and brightening.[15]

It has a radio jet consisting of a northeast and a southwest region, caused by interactions with the interstellar medium.[16]

In February 2022 the European Southern Observatory found a cloud of cosmic dust at the centre of Messier 77 hiding a supermassive black hole.[17]

In November 2022, the IceCube collaboration announced the detection of a neutrino source emitted by the active galactic nucleus of Messier 77.[18][19] It is the second detection by IceCube after TXS 0506+056, and only the fourth known source including SN1987A and solar neutrinos.

  1. ^ a b Cite error: The named reference Skrutskie2006 was invoked but never defined (see the help page).
  2. ^ a b c d Cite error: The named reference ned was invoked but never defined (see the help page).
  3. ^ a b c Cite error: The named reference xiv was invoked but never defined (see the help page).
  4. ^ "Messier 77". SEDS Messier Catalog. Retrieved 30 April 2022.
  5. ^ a b Cite error: The named reference vaucoulerus1991 was invoked but never defined (see the help page).
  6. ^ Cite error: The named reference messier was invoked but never defined (see the help page).
  7. ^ Cite error: The named reference simbad was invoked but never defined (see the help page).
  8. ^ a b Cite error: The named reference jonesbook1991 was invoked but never defined (see the help page).
  9. ^ Cite error: The named reference deVaucouleurs1963 was invoked but never defined (see the help page).
  10. ^ Cite error: The named reference Ann2015 was invoked but never defined (see the help page).
  11. ^ Cite error: The named reference Thronson1989 was invoked but never defined (see the help page).
  12. ^ a b c Cite error: The named reference Alexander2000 was invoked but never defined (see the help page).
  13. ^ Cite error: The named reference deVaucouleurs1973 was invoked but never defined (see the help page).
  14. ^ Cite error: The named reference Wood was invoked but never defined (see the help page).
  15. ^ Cite error: The named reference King was invoked but never defined (see the help page).
  16. ^ Gallimore, J. F.; Baum, S. A.; O'Dea, C. P.; Pedlar, A. (1 February 1996). "The Subarcsecond Radio Structure in NGC 1068. I. Observations and Results". The Astrophysical Journal. 458: 136. doi:10.1086/176798. ISSN 0004-637X.
  17. ^ Observatory, European Southern (16 February 2022). "Supermassive Black Hole Caught Hiding in an Immense Ring of Cosmic Dust". SciTechDaily. Retrieved 21 February 2022.
  18. ^ IceCube Collaboration*†; Abbasi, R.; Ackermann, M.; Adams, J.; Aguilar, J. A.; Ahlers, M.; Ahrens, M.; Alameddine, J. M.; Alispach, C.; Alves, A. A.; Amin, N. M.; Andeen, K.; Anderson, T.; Anton, G.; Argüelles, C. (4 November 2022). "Evidence for neutrino emission from the nearby active galaxy NGC 1068". Science. 378 (6619): 538–543. arXiv:2211.09972. Bibcode:2022Sci...378..538I. doi:10.1126/science.abg3395. ISSN 0036-8075. PMID 36378962. S2CID 253320297.
  19. ^ Staff. "IceCube neutrinos give us first glimpse into the inner depths of an active galaxy". IceCube. Retrieved 23 November 2022.