Messier 95, also known as M95 or NGC 3351, is a

barred spiral galaxy A barred spiral galaxy is a spiral galaxy with a central bar-shaped structure composed of stars. Bars are found in about two thirds of all spiral galaxies, and generally affect both the motions of stars and interstellar gas within spiral galaxies ...

about 33 million light-years away in the

zodiac The zodiac is a belt-shaped region of the sky that extends approximately 8° north or south (as measured in celestial latitude) of the ecliptic, the apparent path of the Sun across the celestial sphere over the course of the year. The pat ...

constellation Leo. 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 born i ...

in 1781, and catalogued by compatriot

Charles Messier Charles Messier (; 26 June 1730 – 12 April 1817) was a French astronomer. He published an astronomical catalogue consisting of 110 nebulae and star clusters, which came to be known as the ''Messier objects''. Messier's purpose ...

four days later. In 2012 its most recent supernova was discovered. The galaxy has a morphological classification of SB(r)b, with the SBb notation indicating it is a barred spiral with arms that are intermediate on the scale from tightly to loosely wound, and an "(r)" meaning an inner ring surrounds the bar. The latter is a ring-shaped, circumnuclear star-forming region with a diameter of approximately . The spiral structure extends outward from the ring. Its ring structure is about (solar masses) in molecular gas and yields a star formation rate of yr⁻¹. The star formation is occurring in at least five regions with diameters between 100 and 150 pc that are composed of several star clusters ranging in size from 1.7 to 4.9 pc. These individual clusters contain of stars, and may be on the path to forming

globular cluster A globular cluster is a spheroidal conglomeration of stars. Globular clusters are bound together by gravity, with a higher concentration of stars towards their centers. They can contain anywhere from tens of thousands to many millions of membe ...

s. A

Type II supernova A Type II supernova (plural: ''supernovae'' or ''supernovas'') results from the rapid collapse and violent explosion of a massive star. A star must have at least 8 times, but no more than 40 to 50 times, the mass of the Sun () to undergo th ...

, designated as SN 2012aw, was discovered within in 2012. The

light curve In astronomy, a light curve is a graph of light intensity of a celestial object or region as a function of time, typically with the magnitude of light received on the y axis and with time on the x axis. The light is usually in a particular frequ ...

of this displayed great flattening after 27 days, thus classifying it as a Type II-P, or "plateau", core-collapse supernova. The disappearance of the progenitor star was later confirmed from near-infrared imaging of the region. The brightness from the presumed

red supergiant Red supergiants (RSGs) are stars with a supergiant luminosity class ( Yerkes class I) of spectral type K or M. They are the largest stars in the universe in terms of volume, although they are not the most massive or luminous. Betelgeuse and Ant ...

progenitor allowed its mass to be estimated as . M95 is one of several galaxies within the

M96 Group The M96 Group (also known as the Leo I Group) is a group of galaxies in the constellation Leo. This group contains between 8 and 24 galaxies, including three Messier objects. It also contains the Leo Ring. The group is one of many groups tha ...

, a

group of galaxies A galaxy group or group of galaxies (GrG) is an aggregation of galaxies comprising about 50 or fewer gravitationally bound members, each at least as luminous as the Milky Way (about 1010 times the luminosity of the Sun); collections of galaxies ...

in the constellation Leo, the other

Messier objects The Messier objects are a set of 110 astronomical objects catalogued by the French astronomer Charles Messier in his ''Catalogue des Nébuleuses et des Amas d'Étoiles'' (''Catalogue of Nebulae and Star Clusters''). Because Messier was only in ...

of which are M96 and M105.

References

External links

*
SEDS: Spiral Galaxy M95
* * {{Ngc35 Barred spiral galaxies Messier 095 Messier 095

095 95 or 95th may refer to: * 95 (number) * one of the years 95 BC, AD 95, 1995, 2095, etc. * 95th Division (disambiguation) * 95th Regiment ** 95th Regiment of Foot (disambiguation) * 95th Squadron (disambiguation) * Atomic number 95: americium *M ...

Messier 095 05850 32007 17810320 Discoveries by Pierre Méchain

See also

References

External links