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Messier 77

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Messier 77 (also known as NGC 1068) is a barred spiral galaxy about 47.0 million light-years away in the constellation Cetus. 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 a Seyfert 2 galaxy.[1]

History

Discovery

Messier 77 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[2]. Both Messier and William Herschel described this galaxy as a star cluster[2]. Today, however, the object is known to be a galaxy.

References

  1. ^ Cite error: The named reference xiv was invoked but never defined (see the help page).
  2. ^ a b K. G. Jones (1991). Messier's Nebulae and Star Clusters (2nd edition ed.). Cambridge: Cambridge University Press. ISBN 0-521-37079-5. {{cite book}}: |edition= has extra text (help)