Messier Index/M77

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Cetus A
Spiral Galaxy M77
Observation data (w:J2000 epoch)
Constellationw:Cetus
Right ascension2h 42m 40.7s[1]
Declination-00° 00′ 48″[1]
Redshift1137 ± 3 km/s[1]
Distance47.0 Mly (14.4 Mpc)[2]
Type(R)SA(rs)b[1]
Apparent dimensions (V)7′.1 × 6′.0[1]
Apparent magnitude (V)9.6[1]
Notable featuresOne of the biggest galaxies
of w:Messier's catalog.
Inclination estimated to be 40°.[3]
Other designations
Cetus A, M77, NGC 1068, UGC 2188, PGC 10266, Arp 37[1]

Messier 77 (also known as NGC 1068) is a barred spiral galaxy about 47 million w:light-years away in the w:constellation w:Cetus. Messier 77 is an w:active galaxy with an w: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 w:VLBA and w:VLA. The hot dust around the nucleus was subsequently measured in the mid-infrared by the MIDI instrument at the w:VLTI. It is the brightest[4] w:Seyfert galaxy and is of type 2.[2]

M77, amateur image. Courtesy of Hunter Wilson

Messier 77's diameter is a 170,000 light-years.

History

Messier 77 was discovered by w:Pierre Méchain in w:1780, who originally described it as a nebula. Méchain then communicated his discovery to w:Charles Messier, who subsequently listed the object in his catalog.[5] Both Messier and w:William Herschel described this galaxy as a star cluster.[5] Today, however, the object is known to be a galaxy.

External links

References

  1. a b c d e f g "NASA/IPAC Extragalactic Database". Results for NGC 1068. Retrieved 2006-11-18.
  2. a b "Pattern Speeds BIMA-SONG Galaxies with Molecule-Dominated ISMs Using the Tremaine-Weinberg Method". Bland-Hawthorn et al. (1997). Retrieved 2006-08-31.
  3. "Pattern Speeds BIMA-SONG Galaxies with Molecule-Dominated ISMs Using the Tremaine-Weinberg Method". (Schinnerer et al. 2000). Retrieved 2006-08-31.
  4. de Vaucouleurs, Gérard (w:April 1 w:1973), "Southern Galaxies.VI. Luminosity Distribution in the Seyfert Galaxy NGC 1566", Astrophysical Journal, 181: 31–50, doi:10.1086/152028 {{citation}}: Check date values in: |date= (help)CS1 maint: date and year (link)
  5. a b K. G. Jones (1991). Messier's Nebulae and Star Clusters (2nd ed.). Cambridge: Cambridge University Press. ISBN 0-521-37079-5.