Messier 77 or
M77, also known as
NGC 1068 and the
Squid Galaxy, is a
barred spiral galaxy about 47 million
light-years away in the
constellationCetus. 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. Both Messier and
William Herschel described this galaxy as a star cluster. Today, however, the object is known to be a galaxy. The
morphological classification of NGC 1068 in the
De Vaucouleurs system is (R)SA(rs)b, 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. Ann
et al. (2015) gave it a class of SAa, suggesting tightly wound arms. However,
infrared images of the inner part of the galaxy reveal a prominent bar not seen in visual light, and for this reason it is now considered a barred spiral.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 and one of the closest and best-studied type 2
Seyfert galaxies, forming a prototype of this class.M77 Type II Supernova, Nov. 2018X-ray source 1H 0244+001 in Cetus has been identified as Messier 77. 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. In February 2022 The European Southern Observatory found a cloud of cosmic dust at the centre of Messier 77 hiding a supermassive
black hole.
Source: Wikipedia 
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