M58 is a magnitude +9.8 barred spiral galaxy that's one of the brightest members of the Virgo cluster. At a distance of 68 million light-years it's one of the furthest objects in the Messier Catalogue, but bright enough to be visible in large binoculars and small telescopes. Although not realised at the time of discovery, M58 was the most distant object - up to that date - ever observed. It's best seen during the months of March, April and May.
The centre of the Virgo cluster is positioned approximately halfway along a line connecting Denebola (β Leo - mag. +2.1) to Vindemiatrix (ε Vir - mag. +2.8). M58 is located a few degrees southeast of the central region. Positioned a degree east of M58 are M59 and M60, with M89 located a degree northwest of M58.
This galaxy was one of Charles Messier original discoveries, which he found on April 15, 1779. On the same night he located elliptical galaxies M59 and M60, which were discovered a few days earlier by Johann Gottfried Koehler. Along with M91, M95 and M109, M58 is one of four barred spirals in the Messier catalogue.
M58 is a fine galaxy for backyard observers. It's visible in larger binoculars (e.g. 20x80s), appearing as a faint small near circular haze of light. A 100mm (4-inch) scope will easily show the bright nucleus. With a 200mm (8-inch) telescope under dark skies and good seeing conditions, it's possible to see hints of the central bar structure. Larger scopes show subtle details but not a great deal more. In total, the galaxy covers 6.0 x 4.8 arc minutes of apparent sky. Despite not being terrifically detailed, it's large and bright enough to be rewarding through most backyard scopes. Some 30 arc minutes southwest of M58 are a curious pair of interacting galaxies, NGC 4567 and NGC 4568, popularly known as the Siamese Twins.
M58 has an active galactic nucleus, which contains a supermassive black hole and some starburst activity. Two supernovae have been observed in M58, a type II at mag. +13.5 in 1998 and a mag. +12.2 type I a year later.
The galaxy is one of the earliest recognised spiral galaxies and was listed by Lord Rosse as one of 14 "spiral nebulae" discovered to 1850.
M58 Data Table
|Object Type||Barred spiral galaxy|
|Distance (light-years)||68 Million|
|RA (J2000)||12h 37m 44s|
|DEC (J2000)||+11d 49m 05s|
|Apparent Size (arc mins)||6.0 x 4.8|
|Number of Stars||400 Billion|
|Notable Feature||M58 is one of the brightest galaxies in the Virgo cluster|