ESO'sVery Large Telescope image of Messier 96, also known as NGC 3368. It shows its core displaced from the centre, its gas and dust are distributed asymmetrically and its spiral arms are ill-defined.
It was discovered by French astronomerPierre Méchain in 1781.[a] After communicating his finding, French astronomerCharles Messier confirmed the finding four days later and added it to his catalogue of nebulous objects.
Finding this object is burdensome with large binoculars. Ideal minimum resolution, in agood sky, is via a telescope of 25.4 cm (10.0 in)aperture, to reveal itsthree-by-five-arcminute halo with a brighter core region.[4]
This complex galaxy is inclined by an angle of about 53° to the line of sight from theEarth, which is oriented at aposition angle of 172°.
It is categorized as a double-barred spiral galaxy with a small inner bulge through the core along with an outer bulge. The nucleus displays a weak level of activity of theLINER2 type. Variations inultraviolet emission from the core suggest the presence of asupermassive black hole. Estimates for the mass of this object range from1.5×106 to4.8×107solar masses (M☉).[5]
On May 9, 1998 asupernova was discovered in this galaxy by Mirko Villi. Designated SN 1998bu, this was aType Ia supernova explosion.[6] It reached maximum brightness on May 21 at about magnitude 11.6, then steadily faded.[7][8] Observations of the ejecta a year later showed creation of 0.4 solar masses of iron. Thespectrum of thesupernova remnant confirmed too radioactive56Co, which decays into56Fe.[9]
Messier 96 is about the same mass and size as theMilky Way. It is a very asymmetric galaxy; its dust and gas are unevenly spread throughout its weak spiral arms, and its core is just offset from the midpoint of its extremes. Its arms are also asymmetrical, thought to have been influenced by the gravitational pull of other galaxies within its group.
Messier 96 is being studied as part of a survey of 50 nearby galaxies known as the Legacy ExtraGalacticUV Survey (LEGUS),[10] providing an unprecedented view of star formation within the local universe.
^Meikle, P.; Hernandez, M. (2000), "Infrared and optical study of the type Ia SN 1998bu in M96",Memorie della Societa Astronomica Italiana,71 (2):299–306,arXiv:astro-ph/9902056,Bibcode:2000MmSAI..71..299M.
