Messier 58: Barred Spiral Galaxy in Virgo
- Catalog
- M58 · NGC 4579
- Type
- Barred spiral galaxy
- Constellation
- Virgo
- Best season
- Spring evenings
- Magnitude
- 9.8
- Apparent size
- 5.5′ × 4.5′
- Distance
- 62,000,000 light-years
- Position (J2000)
- 12h 37.7m, +11° 49′
- Best seen with
- Larger telescope
- Discovered
- Charles Messier, 1779
M58 is one of the brighter spirals in the Virgo Cluster. It sits at the western end of a short row with M59 and M60, and close to the rich field around M87 and Markarian's Chain.
What it is
M58 is a barred spiral galaxy about 62 million light-years away. Its 5.5-arcminute length works out to roughly 100,000 light-years, close to the size of the Milky Way. It is one of only a few barred spirals in Messier's list, along with M91, M95 and M109, though some astronomers class it as halfway between barred and normal. Two supernovae have been seen in it: 1988A and 1989M.
When to see it
M58 is a spring object. It is highest around midnight in early April and well placed in the evening from April into June. From about 40°N it climbs to about 62° in the south. It is also visible from most of the Southern Hemisphere, lower in the north during their autumn.
How to find it
The easiest route uses Vindemiatrix (Epsilon Virginis). Move about 4½° due west of it to reach M60, which has the 5th-magnitude star Rho Virginis about 1½° to its south-southwest. From M60, M59 is less than half a degree to the west-northwest, and M58 is about 1° farther west. Coming from the other side, M58 is about 1° south-southeast of M89 and about 2° east of M87, at the southeast end of the Markarian's Chain region.
What you will see
M58 is a small, faint target. In a small telescope under dark skies it looks like a faint oval glow with a brighter center, much like the elliptical galaxies around it. A 200 mm telescope shows an uneven halo around the bright core, and steady viewing may show the bar as a slight east-west stretch of the center. From suburban skies it is hard to see in anything smaller than 150 mm. Use medium power and sweep slowly; several other Virgo galaxies may drift into the same field.
History
Charles Messier found M58 on April 15, 1779, while following the comet of that year; on the same night he also found M59 and M60. Lord Rosse later listed M58 among the first spiral nebulae recognized before 1850.