Messier 95 Explained

Messier 95
Epoch:J2000
Ra:[1]
Constellation Name:Leo
Z:778 ± 4 km/s
Dist Ly:32.6 ± 1.4 Mly (10.0 ± 0.4 Mpc)[2]
Type:SB(r)b
Appmag V:9.7[3]
Size V:3′.1 × 2′.9
Names:NGC 3351, UGC 5850, PGC 32007

Messier 95, also known as M95 or NGC 3351, is a barred spiral galaxy about 33 million light-years away in the zodiac constellation Leo. It was discovered by Pierre Méchain in 1781, and catalogued by compatriot Charles Messier 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 70000ly.[4] 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 clusters.

A Type II supernova, designated as SN 2012aw, was discovered in M95 in 2012.[5] [6] [7] The light curve 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 progenitor allowed its mass to be estimated as .

M95 is one of several galaxies within the M96 Group, a group of galaxies in the constellation Leo, the other Messier objects of which are M96 and M105.[8] [9] [10] [11]

See also

External links

Notes and References

  1. Web site: NASA/IPAC Extragalactic Database . Results for NGC 3351 . 2007-10-03.
  2. Jensen, Joseph B. . Tonry, John L. . Barris, Brian J. . Thompson, Rodger I. . Liu, Michael C. . Rieke, Marcia J. . Ajhar, Edward A. . Blakeslee, John P. . 4 . 2003 . Measuring Distances and Probing the Unresolved Stellar Populations of Galaxies Using Infrared Surface Brightness Fluctuations . . 583 . 2 . 712–726 . 2003ApJ...583..712J . 10.1086/345430. astro-ph/0210129 . 551714 .
  3. Web site: Messier 95 . 30 April 2022 . SEDS Messier Catalog.
  4. L. . Colina . M. L. . Garcia Vargas . J. M. . Mas-Hesse . A. . Alberdi . A. . Krabbe . 1997 . Nuclear Star-forming Structures and the Starburst–Active Galactic Nucleus Connection in Barred Spirals NGC 3351 and NGC 4303 . . 484 . 1 . L41–L45 . 1997ApJ...484L..41C . 10.1086/310766. free .
  5. Web site: Deep Sky Videos . . 19 March 2012.
  6. Web site: Supernova 2012aw: the pictures! . 19 March 2012 . 20 October 2019 . https://web.archive.org/web/20191020161204/http://blogs.discovermagazine.com/badastronomy/2012/03/20/supernova-2012aw-the-pictures/ . dead .
  7. Web site: List of Recent Supernovae . 8 April 2012.
  8. Book: R. B. . Tully . 1988 . Nearby Galaxies Catalog . . 978-0-521-35299-4.
  9. P. . Fouque . E. . Gourgoulhon . P. . Chamaraux . G. . Paturel . Groups of galaxies within 80 Mpc. II – The catalogue of groups and group members . . 1992 . 93 . 211–233 . 1992A&AS...93..211F.
  10. A. . Garcia . 1993 . General study of group membership. II – Determination of nearby groups . . 100 . 47–90 . 1993A&AS..100...47G.
  11. G. . Giuricin . C. . Marinoni . L. . Ceriani . A. . Pisani . Nearby Optical Galaxies: Selection of the Sample and Identification of Groups . . 2000 . 543 . 1 . 178–194 . 2000ApJ...543..178G . 10.1086/317070 . astro-ph/0001140 . 9618325 . 1.