Virgo is the second-largest of the 88 recognized constellations and the largest of the zodiac constellations, covering about 1,294 square degrees of sky. Its brightest star is Spica (Alpha Virginis), a multiple-star system with a combined apparent magnitude of about +1.0.
Virgo is visible from most inhabited latitudes and is especially prominent in the Northern Hemisphere during spring. Around May, it is well placed in the evening sky between Leo to the west and Libra to the east.
For deep-sky observers, Virgo is particularly notable for its extraordinary concentration of galaxies. The constellation contains 11 Messier objects, many of them members of the nearby Virgo Cluster, as well as one of the brightest quasars visible from Earth.
Virgo Cluster
The Virgo Cluster is the nearest large galaxy cluster to the Milky Way and lies roughly 54 million light-years away. It contains well over a thousand galaxies, with estimates commonly extending to around 2,000 members. Giant elliptical galaxies such as M87 and M49 are among its most prominent members.
The cluster is part of the much larger network of galaxies in our cosmic neighborhood. Older descriptions often referred to the Milky Way, Local Group and Virgo Cluster as components of the Virgo Supercluster, although modern large-scale mapping places our Local Group within the still larger Laniakea Supercluster.
Because many Virgo Cluster galaxies are comparatively bright and concentrated within a relatively small area of sky, Virgo is one of the richest regions for amateur galaxy observing.
Messier 49 (M49, NGC 4472)
Messier 49 is a giant elliptical galaxy about 60 million light-years away. With an apparent magnitude of around 9.4, it is one of the brightest galaxies in the Virgo Cluster and can be seen through binoculars under favorable dark-sky conditions.
Charles Messier discovered M49 in 1771, making it the first member of the Virgo Cluster to be added to his catalog. Unlike a spiral galaxy with conspicuous arms and dust lanes, M49 appears as a comparatively smooth concentration of older stars.
The galaxy contains an exceptionally rich system of nearly 6,000 globular clusters. By comparison, the Milky Way has only around 150 known globular clusters. At M49’s center lies a supermassive black hole estimated to contain roughly 565 million solar masses.
M49 also shows evidence of interaction with smaller neighboring galaxies, providing astronomers with an example of how giant elliptical galaxies can continue growing by absorbing smaller systems.
Messier 58 (M58, NGC 4579)
Messier 58 is a barred spiral galaxy roughly 60 million light-years away and a member of the Virgo Cluster. It has an apparent magnitude of about 10.5 and is one of several Messier galaxies concentrated in this part of the sky.
M58 contains an active galactic nucleus powered by matter falling toward its central supermassive black hole. Its spiral structure is less conspicuous than that of many nearby spiral galaxies, partly because star formation in the galaxy is relatively subdued.
Two supernovae were observed in M58 during the 20th century: SN 1988A and SN 1989M. Through a small telescope, the galaxy generally appears as a faint oval glow with a brighter center, while larger apertures and dark skies make its extended structure easier to detect.
Messier 87 (M87, NGC 4486)
Messier 87 is a giant elliptical galaxy about 54 million light-years from Earth and one of the dominant galaxies of the Virgo Cluster. It contains several trillion stars and an extraordinary population of roughly 15,000 globular clusters.
M87 is particularly famous for the supermassive black hole at its center. In 2019, the Event Horizon Telescope collaboration released the first image of a black hole’s shadow, using observations of this object. The black hole has a mass of about 6.5 billion Suns.
A spectacular jet of energetic particles extends thousands of light-years from M87’s nucleus. Powered by activity around the central black hole, material in the jet travels at velocities close to the speed of light and can be detected across several parts of the electromagnetic spectrum.
Despite its enormous physical scale, M87 is within reach of amateur observers. Under dark skies, a small telescope shows it as a compact, hazy patch near the Virgo-Leo border.
Sombrero Galaxy (M104, NGC 4594)
Located about 28 million light-years away, the Sombrero Galaxy is one of the most distinctive galaxies in the night sky. Its bright central bulge and dark band of dust give it the hat-like appearance from which its popular name is derived.
M104 is a spiral galaxy seen nearly edge-on. Its dark dust lane contains material associated with star formation, while its enormous central bulge dominates the galaxy’s visible appearance.
The Sombrero also possesses an unusually rich population of globular clusters. Hubble observations have resolved nearly 2,000 of them, around ten times the number known in the Milky Way. At the galaxy’s center is a supermassive black hole with a mass of around one billion Suns.
With an apparent magnitude of about 8, M104 is a popular amateur target. It lies in the southern part of Virgo, roughly 11 degrees west of Spica, and its bright central region can be detected through relatively modest telescopes.
3C 273
3C 273 is a quasar about 2.5 billion light-years away and one of the most distant objects accessible to experienced amateur observers. Despite that enormous distance, it has an apparent magnitude of around 13, making it the optically brightest quasar in Earth’s sky.
In 1963, astronomer Maarten Schmidt identified the enormous redshift of 3C 273, establishing the true extragalactic nature of quasars and helping transform our understanding of these mysterious objects.
A quasar is the intensely luminous nucleus of an active galaxy, powered by material falling toward a supermassive black hole. In the case of 3C 273, the tremendous energy output is accompanied by a jet extending roughly 200,000 light-years from the nucleus.
Although 3C 273 was sometimes loosely grouped with blazars in older descriptions, it is more accurately described as a radio-loud quasar. Its jet is not pointed as directly toward Earth as the jets of objects normally classified as blazars.
Its extraordinary luminosity is difficult to appreciate from its star-like appearance. If 3C 273 were only a few dozen light-years from Earth instead of billions of light-years away, it would appear about as bright as the Sun in our sky.
