M58 is one of the 4 barred spiral galaxies in Messier's catalog (the others are M91, M95, and M109, though it is sometimes classified as intermediate between normal and barred spirals. It is one of the brightest galaxies in the Virgo cluster.
Smaller telescopes let it look similar to the Virgo ellipticals, showing only its bright nucleus. Under good conditions, 4-inch or larger scopes show a halo of uneven brightness with condensations which seem to coincide with brighter areas of the spiral arms. A suggestion of M58's bar may be noticed with telescopes starting from 8-inch, as an "extension of the central nucleus in an EW direction" (Kenneth Glyn Jones).
Two supernovae have been observed in M58: the type II supernova 1988A, found by Ikeya on January 18, 1988, 40" south of the nucleus at mag 13.5, and the type I supernova 1989M, discovered by Kimeridze on June 28, 1989 at mag 12.2 and 33"N, 44"W of M58's center.
|Right ascension||12 : 35.1 (hours : minutes)|
|Declination||+12 : 05 (degrees : minutes)|