Galaxies Messier 95, Messier 96

History

M 95 and M 96 were discovered by Pierre Méchain on March 20, 1781 and cataloged by Charles Messier on the 24th of the same month. He wrote about M 95: «Nebula without a star, in Leo, above star 1: the light is very weak.» About M 96 he wrote: «Nebula without a star, in Leo, next to the previous one; this is less obvious, both are on the parallels of Regulus: they resemble the two nebulae nos. 84 and 86 in Virgo. M. Méchain had seen both of them on March 20, 1781.» [281]

Messier 95
Messier 95: Image taken with the Hubble Space Telescope [215]

Physical Properties of M 95

M 95 is a beautiful barred spiral galaxy and has around 40 billion stars. It is located about 33 million light years away and belongs to the Leo I group of galaxies, which includes M 95, M 105 and a large number of other galaxies. Many young, blue stars appear in the spiral arms. They are tightly wound around the center of the galaxy and are almost circular. In March 2016, the supernova SN 2012aw was discovered in the outer spiral arms of this galaxy. The star that became a supernova was a large, red supergiant with 26 times the mass of our sun. [196, 215]

«Catalogue of Principal Galaxies (PGC)», Paturel et al. 1989 [144]
DesignationsPGC 32007: NGC 3351, UGC 5850, MCG 2-28-1, M 95, CGCG 66-4, IRAS 10413+1158
Right Ascension (J2000.0)10h 43m 58.0s
Declination (J2000.0)+11° 42' 14"
Morphological TypeSBR
Dimensions7.3' x 4.4'
Visual Magnitude10.6 mag
Radial Velocity (HRV)778 km/s
Position Angle13°

Physical Properties of M 96

What is remarkable about the spiral galaxy M 96 is that its core is not exactly in the galactic center. It's about 35 million light years away. Mass and size roughly correspond to those of our Milky Way. [215]

In the eastern part of the galaxy we look through the spiral arms to the distant galaxy 2MFGC 08391 with extreme edge position. Due to the expansion of the universe, it is moving away at a speed of 16'530 km/s, which corresponds to a distance of about 244 Mpc (796 million light years). [194]

Messier 96
Messier 96: Image taken with the Hubble Space Telescope [215]
Messier 96
Messier 96: With the edge-on galaxy 2MFGC 8391 behind it: Excerpt from the Sloan Digitized Sky Survey [147]
«Catalogue of Principal Galaxies (PGC)», Paturel et al. 1989 [144]
DesignationsPGC 32192: NGC 3368, UGC 5882, MCG 2-28-6, M 96, CGCG 66-13, IRAS 10441+1205
Right Ascension (J2000.0)10h 46m 45.2s
Declination (J2000.0)+11° 49' 15"
Morphological TypeSBR
Dimensions7.8' x 5.2'
Visual Magnitude10.1 mag
Radial Velocity (HRV)898 km/s
Position Angle

Finder Chart

The two galaxies are located in the constellation Leo, about two degrees south on the center of the connecting lines of the two stars Chertan (θ Leonis) and Regulus (α Leonis). Almost one degree northeast of galaxy M 96 is the triple galaxy group M 105, NGC 3384, NGC 3389.

Chart M 95
Chart created using SkySafari 6 Pro and STScI Digitized Sky Survey. [149, 160]

Visual Observation

The two galaxies are clearly visible with a smaller telescope. With an average brightness of 10.5 mag, they are not too much of a challenge. However, they are all the more clear and brighter. Unfortunately, none of the four galaxies give off any structures and the fine spiral arms at M 95 and M 96 are only visible on larger telescopes. [192]

Eduard von Bergen

References

144Catalogue of Principal Galaxies (PGC); Paturel G., Fouque P., Bottinelli L., Gouguenheim L.; Astron. Astrophys. Suppl. Ser. 80, 299 (1989); cdsarc.unistra.fr/viz-bin/cat/VII/119 (2021-02-18)
147Aladin Lite; aladin.u-strasbg.fr/AladinLite (2020-12-23)
149SkySafari 6 Pro, Simulation Curriculum; skysafariastronomy.com
160The STScI Digitized Sky Survey; archive.stsci.edu/cgi-bin/dss_form
192Deep-Sky Guide; fernrohr.ch/1d_deep-sky-guide.html (2020-12-25)
194NASA/IPAC Extragalactic Database (NED); ned.ipac.caltech.edu (2020-12-27)
196Celestial Atlas by Curtney Seligman; cseligman.com/text/atlas.htm (2020-12-28)
215Explore - The Night Sky | Hubble’s Messier Catalog; nasa.gov/content/goddard/hubble-s-messier-catalog (2020-12-31)
281«Catalogue Nébuleuses et des Amas D'Étoiles» Observées à Paris, par M. Messier, à l'Observatoire de la Marine, hôtel de Clugni, rue des Mathurins. «Connoissance des temps ou connoissance des mouvements célestes, pour l'année bissextile 1784 » Page 227; gallica.bnf.fr/ark:/12148/bpt6k6514280n/f235 (2021-02-21)