Messier 105 or M105, also known as NGC 3379, is an

elliptical galaxy An elliptical galaxy is a type of galaxy with an approximately ellipsoidal shape and a smooth, nearly featureless image. They are one of the four main classes of galaxy described by Edwin Hubble in his Hubble sequence and 1936 work ''The Rea ...

36.6 million light-years away in the equatorial constellation of

Leo Leo or Léo may refer to: Acronyms * Law enforcement officer * Law enforcement organisation * ''Louisville Eccentric Observer'', a free weekly newspaper in Louisville, Kentucky * Michigan Department of Labor and Economic Opportunity Arts an ...

. It is the biggest elliptical galaxy in the Messier catalogue that is not in the Virgo cluster. It was discovered by

Pierre Méchain Pierre François André Méchain (; 16 August 1744 – 20 September 1804) was a French astronomer and surveyor who, with Charles Messier, was a major contributor to the early study of deep-sky objects and comets. Life Pierre Méchain was bo ...

in 1781, just a few days after he discovered the nearby galaxies Messier 95 and Messier 96. This galaxy is one of a few not object-verified by

Messier Messier may refer to: People with the surname * Charles Messier, French astronomer *Éric Messier, former NHL defenseman *George Messier, French inventor * Jean-Marie Messier, former CEO of Vivendi Universal *Marc Messier, Canadian actor from Quebe ...

so omitted in the editions of his Catalogue of his era. It was appended when Helen S. Hogg found a letter by Méchain locating and describing this object which matched those aspects under its first-published name, NGC 3379. It has a morphological classification of E1, indicating a standard elliptical galaxy with a

flattening Flattening is a measure of the compression of a circle or sphere A sphere () is a Geometry, geometrical object that is a solid geometry, three-dimensional analogue to a two-dimensional circle. A sphere is the Locus (mathematics), set o ...

of 10%. The major axis is aligned along a position angle of 71°. Isophotes of the galaxy are near perfect ellipses, twisting no more than 5° out of alignment, with changes in ellipticity of no more than 0.06. There is no fine structure apparent in the isophotes, such as ripples. Observation of giant stars in the halo indicate there are two general populations: a dominant metal-rich subpopulation and a weaker metal-poor group. Messier 105 is known to have a

supermassive black hole A supermassive black hole (SMBH or sometimes SBH) is the largest type of black hole, with its mass being on the order of hundreds of thousands, or millions to billions of times the mass of the Sun (). Black holes are a class of astronomical obj ...

at its core whose mass is estimated to be between and . The galaxy has a weak active galactic nucleus of the LINER type with a spectral class of L2/T2, meaning no broad Hα line and intermediate emission line ratios between a LINER and a H II region. The galaxy also contains a few young

star A star is an astronomical object comprising a luminous spheroid of plasma held together by its gravity. The nearest star to Earth is the Sun. Many other stars are visible to the naked eye at night, but their immense distances from Earth make ...

s and stellar clusters, suggesting some elliptical galaxies still form new stars, but very slowly. This galaxy, along with its companion the barred lenticular galaxy NGC 3384, is surrounded by an enormous ring of neutral hydrogen with a radius of and a mass of where star formation has been detected. Messier 105 is one of several galaxies within the M96 Group (also known as the Leo I Group), a group of galaxies in the constellation

, the other Messier objects of which are M95 and M96.

References and footnotes

External links

*
"StarDate: M105 Fact Sheet"

* {{Ngc35 Elliptical galaxies M96 Group Leo (constellation)

105 105 may refer to: *105 (number), the number *AD 105, a year in the 2nd century AD *105 BC, a year in the 2nd century BC * 105 (telephone number) * 105 (MBTA bus) * 105 (Northumberland) Construction Regiment, Royal Engineers, an English military unit ...

Messier 105 05902 32256 17810324 Discoveries by Pierre Méchain

See also

References and footnotes

External links