Astronomy:Messier 95
| Messier 95 | |
|---|---|
| File:M95 - HST - Potw1841a.tiff Hubble Space Telescope image of Messier 95 | |
| Observation data (J2000 epoch) | |
| Constellation | Leo |
| Right ascension | 10h 43m 57.7s[1] |
| Declination | +11° 42′ 14″[1] |
| Redshift | 778 ± 4 km/s[1] |
| Distance | 32.6 ± 1.4 Mly (10.0 ± 0.4 Mpc)[2] |
| Apparent magnitude (V) | 9.7[3] |
| Characteristics | |
| Type | SB(r)b[1] |
| Size | 80,130 ly (24.58 kpc)[1] |
| Apparent size (V) | 3′.1 × 2′.9[1] |
| Other designations | |
| NGC 3351,[1] UGC 5850,[1] PGC 32007[1] | |
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,[1] 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.[4] The latter is a ring-shaped, circumnuclear star-forming region with a diameter of approximately 70,000 light-years (21,000 pc).[5] The spiral structure extends outward from the ring.[4]
Its ring structure is about 3.5×108 M☉ (solar masses) in molecular gas and yields a star formation rate of 0.38 M☉ yr−1.[lower-alpha 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 (1.8–8.7)×106 M☉[lower-alpha 2] of stars, and may be on the path to forming globular clusters.[6]
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.[7][8][9][10]
Supernova
One supernova has been observed in M95:
- SN 2012aw (Type II-P, mag. 15) was discovered by Paolo Fagotti and independently by Jure Skvarc on 16 March 2012.[11][12][13][14] The light curve of this displayed great flattening after 27 days, thus classifying it as a Type II-P, or "plateau", core-collapse supernova.[15] 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 12.5±1.5 M☉.[16]
File:Caught in the act Messier 95.tif

See also
References
- ↑ 1.00 1.01 1.02 1.03 1.04 1.05 1.06 1.07 1.08 1.09 "Results for object MESSIER 095". https://ned.ipac.caltech.edu/byname?objname=MESSIER+095.
- ↑ Jensen, Joseph B.; Tonry, John L.; Barris, Brian J.; Thompson, Rodger I. et al. (2003). "Measuring Distances and Probing the Unresolved Stellar Populations of Galaxies Using Infrared Surface Brightness Fluctuations". Astrophysical Journal 583 (2): 712–726. doi:10.1086/345430. Bibcode: 2003ApJ...583..712J.
- ↑ "Messier 95". https://messier.seds.org/m/m095.html.
- ↑ 4.0 4.1 Buta, Ronald J. et al. (2007), Atlas of Galaxies, Cambridge University Press, pp. 1−25, ISBN 978-0521820486, https://books.google.com/books?id=g-P7dCbB5MEC&pg=PA1.
- ↑ Colina, L.; Garcia Vargas, M. L.; Mas-Hesse, J. M.; Alberdi, A.; Krabbe, A. (1997). "Nuclear Star-forming Structures and the Starburst–Active Galactic Nucleus Connection in Barred Spirals NGC 3351 and NGC 4303". Astrophysical Journal Letters 484 (1): L41–L45. doi:10.1086/310766. Bibcode: 1997ApJ...484L..41C.
- ↑ Hägele, Guillermo F. et al. (June 2007), "Kinematics of gas and stars in the circumnuclear star-forming ring of NGC3351", Monthly Notices of the Royal Astronomical Society 378 (1): 163−178, doi:10.1111/j.1365-2966.2007.11751.x, Bibcode: 2007MNRAS.378..163H
- ↑ Tully, R. B. (1988). Nearby Galaxies Catalog. Cambridge University Press. ISBN 978-0-521-35299-4.
- ↑ Fouque, P.; Gourgoulhon, E.; Chamaraux, P.; Paturel, G. (1992). "Groups of galaxies within 80 Mpc. II – The catalogue of groups and group members". Astronomy and Astrophysics Supplement 93: 211–233. Bibcode: 1992A&AS...93..211F.
- ↑ Garcia, A. (1993). "General study of group membership. II – Determination of nearby groups". Astronomy and Astrophysics Supplement 100: 47–90. Bibcode: 1993A&AS..100...47G.
- ↑ Giuricin, G. et al. (2000). "Nearby Optical Galaxies: Selection of the Sample and Identification of Groups". Astrophysical Journal 543 (1): 178–194. doi:10.1086/317070. Bibcode: 2000ApJ...543..178G.
- ↑ Fagotti, P. (2012). "Supernova 2012aw in M95 = Psn J10435372+1140177". Central Bureau Electronic Telegrams 3054: 1. Bibcode: 2012CBET.3054....1Q. https://ui.adsabs.harvard.edu/abs/2012CBET.3054....1Q.
- ↑ "Deep Sky Videos". https://www.youtube.com/user/DeepSkyVideos?feature=watch.
- ↑ "Supernova 2012aw: the pictures!". http://blogs.discovermagazine.com/badastronomy/2012/03/20/supernova-2012aw-the-pictures/.
- ↑ "SN 2012aw". IAU. https://www.wis-tns.org/object/2012aw.
- ↑ Bayless, Amanda J. et al. (February 2013), "The Long-lived UV "Plateau" of SN 2012aw", The Astrophysical Journal Letters 764 (1): 6, doi:10.1088/2041-8205/764/1/L13, L13, Bibcode: 2013ApJ...764L..13B.
- ↑ Fraser, Morgan (February 2016), "The disappearance of the progenitor of SN 2012aw in late-time imaging", Monthly Notices of the Royal Astronomical Society: Letters 456 (1): L16−L19, doi:10.1093/mnrasl/slv168, Bibcode: 2016MNRAS.456L..16F.
- ↑ "Caught in the act" (in en). https://www.eso.org/public/images/potw1935a/.
External links
- Messier 95 on WikiSky: DSS2, SDSS, GALEX, IRAS, Hydrogen α, X-Ray, Astrophoto, Sky Map, Articles and images
- SEDS: Spiral Galaxy M95
- NASA Astronomy Picture of the Day: Barred Spiral Galaxy M95 (14 March 2007)
- Merrifield, Michael. "Supernova in M95 – SN 2012aw and its progenitor". Deep Sky Videos. Brady Haran. http://www.deepskyvideos.com/videos/other/supernova_M95_star.html.
Coordinates:
10h 43m 57.7s, +11° 42′ 14″
