Constellation | |
Abbreviation | Vir |
---|---|
Genitive | Virginis |
Pronunciation |
|
Symbolism | the Maiden |
Right ascension | 13h |
Declination | −4° |
Quadrant | SQ3 |
Area | 1294 sq. deg. (2nd) |
Main stars | 9, 15 |
Bayer/Flamsteed stars | 96 |
Stars with planets | 29 |
Stars brighter than 3.00m | 3 |
Stars within 10.00 pc (32.62 ly) | 10 |
Brightest star | Spica (α Vir) (0.98 m ) |
Messier objects | 11 |
Meteor showers |
|
Bordering constellations | |
Visible at latitudes between +80° and −80°. Best visible at 21:00 (9 p.m.) during the month of May. |
Virgo is one of the constellations of the zodiac. Its name is Latin for maiden, and its old astronomical symbol is . Between Leo to the west and Libra to the east, it is the second-largest constellation in the sky (after Hydra) and the largest constellation in the zodiac. The ecliptic intersects the celestial equator within this constellation and Pisces. Underlying these technical two definitions, the sun passes directly overhead of the equator, within this constellation, at the September equinox. Virgo can be easily found through its brightest star, Spica.
Virgo is prominent in the spring sky in the Northern Hemisphere, visible all night in March and April. As the largest zodiac constellation, the Sun takes 44 days to pass through it, longer than any other. From 1990 and until 2062, this will take place from September 16 to October 30. It is located in the third quadrant of the Southern Hemisphere (SQ3) and can be seen at latitudes between +80° and -80°.
The bright star Spica makes it easy to locate Virgo, as it can be found by following the curve of the Big Dipper/Plough to Arcturus in Boötes and continuing from there in the same curve ("follow the arc to Arcturus and speed on to Spica"). [1]
Due to the effects of precession, the autumn equinox point lies within the boundaries of Virgo very close to β Virginis. This is one of the two points in the sky where the celestial equator crosses the ecliptic (the other being the vernal equinox point in the constellation of Pisces). From the 18th century to the 4th century BC, the Sun was in Libra on the autumnal equinox, shifting into Virgo thereafter. This point will pass into the neighboring constellation of Leo around the year 2440.
Besides Spica, other bright stars in Virgo include β Virginis (Zavijava), γ Virginis (Porrima), δ Virginis (Auva) and ε Virginis (Vindemiatrix). Other fainter stars that were also given names are ζ Virginis (Heze), η Virginis (Zaniah), ι Virginis (Syrma), κ Virginis (Kang), λ Virginis (Khambalia) and φ Virginis (Elgafar).
The 7 main stars of Virgo form 2 distinct star patterns: Beta, Gamma, Delta, Epsilon and Eta Virginis; form an asterism known as "The Bowl of Virgo". Together with Spica and Theta Virginis, they form a Y shape.
The star 70 Virginis has one of the first known extrasolar planetary systems with one confirmed planet 7.5 times the mass of Jupiter.
The star Chi Virginis has one of the most massive planets ever detected, with a mass of 11.1 times that of Jupiter.
The sun-like star 61 Virginis has three known planets: one is a super-Earth and two are Neptune-mass planets.
SS Virginis is a variable star with a noticeable red color. It varies in magnitude from a minimum of 9.6 to a maximum of 6.0 over approximately one year. [2]
There are 35 verified exoplanets orbiting 29 stars in Virgo, including PSR B1257+12 (three planets), 70 Virginis (one planet), Chi Virginis (one planet), 61 Virginis (three planets), NY Virginis (two planets), and 59 Virginis (one planet).
Because of the presence of a galaxy cluster (consequently called the Virgo Cluster) within its borders 5° to 12° west of ε Vir (Vindemiatrix), this constellation is especially rich in galaxies.
Some examples are Messier 49 (elliptical), Messier 58 (spiral), Messier 59 (elliptical), Messier 60 (elliptical), Messier 61 (spiral), Messier 84 (lenticular), Messier 86 (lenticular), Messier 87 (elliptical and a famous radio source), Messier 89 (elliptical) and Messier 90 (spiral). A noted galaxy that is not part of the cluster is the Sombrero Galaxy (M104), an unusual spiral galaxy. It is located about 10° due west of Spica.
NGC 4639 is a face-on barred spiral galaxy located 78 Mly from Earth (redshift 0.0034). Its outer arms have a high number of Cepheid variables, which are used as standard candles to determine astronomical distances. Because of this, astronomers used several Cepheid variables in NGC 4639 to calibrate type Ia supernovae as standard candles for more distant galaxies. [3]
Virgo possesses several galaxy clusters, one of which is HCG 62. A Hickson Compact Group, HCG 62 is at a distance of 200 Mly from Earth (redshift 0.0137) and possesses a large central elliptical galaxy. It has a heterogeneous halo of extremely hot gas, posited to be due to the active galactic nucleus at the core of the central elliptical galaxy. [3]
M87 is the largest galaxy in the Virgo cluster, and is at a distance of 60 Mly from Earth (redshift 0.0035). It is a major radio source, partially due to its jet of electrons being flung out of the galaxy by its central supermassive black hole. Because this jet is visible in several different wavelengths, it is of interest to astronomers who wish to observe black holes in a unique galaxy. [3] On April 10, 2019, astronomers from the Event Horizon Telescope project released an image of its central black hole; the first direct image of one. [4] [5] [6] With a mass of at least 7.2 billion times that of the Sun, it is the most massive black hole within the immediate vicinity of the Milky Way. [7]
M84 is another elliptical radio galaxy in the constellation of Virgo; it is at a distance of 60 Mly (redshift 0.0035) as well. Astronomers have surmised that the speed of the gas clouds orbiting the core (approximately 400 km/s) indicates the presence of an object with a mass 300 million times that of the sun, which is most likely a black hole. [3]
The Sombrero Galaxy, M104, is an edge-on spiral galaxy located 28 million light-years from Earth (redshift 0.0034). It has a bulge at its center made up of older stars that are larger than normal. It is surrounded by large, bright globular clusters and has a very prominent dust lane made up of polycyclic aromatic hydrocarbons. [3]
NGC 4438 is a peculiar galaxy with an active galactic nucleus, at a distance of 50 Mly from Earth (redshift 0.0035). Its supermassive black hole is ejecting jets of matter, creating bubbles with a diameter of up to 78 ly. [3]
NGC 4261 also has a black hole 20 ly from its center with a mass of 1.2 billion solar masses. It is located at a distance of 45 Mly from Earth (redshift 0.0075), and has an unusually dusty disk with a diameter of 300 ly. Along with M84 and M87, NGC 4261 has strong emissions in the radio spectrum. [3]
Virgo is also home to the quasar 3C 273 which was the first quasar ever to be identified. With a magnitude of ~12.9, it is also the optically brightest quasar in the sky.
In the Babylonian MUL.APIN (c. 10th century BC), part of this constellation was known as "The Furrow", representing the goddess Shala and her ear of grain. One star in this constellation, Spica, retains this tradition as it is Latin for "ear of grain", one of the major products of the Mesopotamian furrow. For this reason the constellation became associated with fertility. [8] The constellation of Virgo in Hipparchus corresponds to two Babylonian constellations: the "Furrow" in the eastern sector of Virgo and the "Frond of Erua" in the western sector. The Frond of Erua was depicted as a goddess holding a palm-frond – a motif that still occasionally appears in much later depictions of Virgo. [9]
Early Greek astronomy associated the Babylonian constellation with their goddess of wheat, agriculture and autumn, Demeter.[ citation needed ] The Romans associated it with their goddess Ceres.[ citation needed ] Alternatively, the constellation was sometimes[ clarification needed ] identified as the virgin goddess Iustitia or Astraea, holding the scales of justice in her hand (that now are separated as the constellation Libra). [10] Another Greek myth from later, Classical times, identifies Virgo as Erigone, the daughter of Icarius of Athens. [11] Icarius, who had been favored by Dionysus and was killed by his shepherds while they were intoxicated after which Erigone hanged herself in grief; in versions[ clarification needed ] of this myth, Dionysus is said to have placed the father and daughter in the stars as Boötes and Virgo respectively. Another figure who is associated with the constellation Virgo was the spring goddess Persephone, [12] [13] [14] [15] the daughter of Zeus and Demeter who had married Hades and resided in the Underworld.
In the Poeticon Astronomicon by Hyginus (1st century BC), Parthenos (Παρθένος) is the daughter of Apollo and Chrysothemis, who died a maiden and was placed among the stars as the constellation. [16] Diodorus Siculus has an alternative account, according to which Parthenos was the daughter of Staphylus and Chrysothemis, sister of Rhoeo and Molpadia (Hemithea). After a suicide attempt she and Hemithea were carried by Apollo to Chersonesus, where she became a local goddess. [17] Strabo also mentions a goddess named Parthenos worshipped throughout Chersonesus. [18]
During the Middle Ages, Virgo sometimes was associated with the Blessed Virgin Mary. [8]
In Greek mythology, the constellation is also associated with the daughter of Zeus, Dike the goddess of justice, who is represented holding the scales of justice.
Capricornus is one of the constellations of the zodiac. Its name is Latin for "horned goat" or "goat horn" or "having horns like a goat's", and it is commonly represented in the form of a sea goat: a mythical creature that is half goat, half fish.
Centaurus is a bright constellation in the southern sky. One of the largest constellations, Centaurus was included among the 48 constellations listed by the 2nd-century astronomer Ptolemy, and it remains one of the 88 modern constellations. In Greek mythology, Centaurus represents a centaur; a creature that is half human, half horse. Notable stars include Alpha Centauri, the nearest star system to the Solar System, its neighbour in the sky Beta Centauri, and HR 5171, one of the largest stars yet discovered. The constellation also contains Omega Centauri, the brightest globular cluster as visible from Earth and the largest identified in the Milky Way, possibly a remnant of a dwarf galaxy.
Canes Venatici is one of the 88 constellations designated by the International Astronomical Union (IAU). It is a small northern constellation that was created by Johannes Hevelius in the 17th century. Its name is Latin for 'hunting dogs', and the constellation is often depicted in illustrations as representing the dogs of Boötes the Herdsman, a neighboring constellation.
Leo is one of the constellations of the zodiac, between Cancer the crab to the west and Virgo the maiden to the east. It is located in the Northern celestial hemisphere. Its name is Latin for lion, and to the ancient Greeks represented the Nemean Lion killed by the mythical Greek hero Heracles as one of his twelve labors. Its old astronomical symbol is (♌︎). One of the 48 constellations described by the 2nd-century astronomer Ptolemy, Leo remains one of the 88 modern constellations today, and one of the most easily recognizable due to its many bright stars and a distinctive shape that is reminiscent of the crouching lion it depicts.
Coma Berenices is an ancient asterism in the northern sky, which has been defined as one of the 88 modern constellations. It is in the direction of the fourth galactic quadrant, between Leo and Boötes, and it is visible in both hemispheres. Its name means "Berenice's Hair" in Latin and refers to Queen Berenice II of Egypt, who sacrificed her long hair as a votive offering. It was introduced to Western astronomy during the third century BC by Conon of Samos and was further corroborated as a constellation by Gerardus Mercator and Tycho Brahe. It is the only modern constellation named after a historic person.
An elliptical galaxy is a type of galaxy with an approximately ellipsoidal shape and a smooth, nearly featureless image. They are one of the four main classes of galaxy described by Edwin Hubble in his Hubble sequence and 1936 work The Realm of the Nebulae, along with spiral and lenticular galaxies. Elliptical (E) galaxies are, together with lenticular galaxies (S0) with their large-scale disks, and ES galaxies with their intermediate scale disks, a subset of the "early-type" galaxy population.
Hydra is the largest of the 88 modern constellations, measuring 1303 square degrees, and also the longest at over 100 degrees. Its southern end borders Libra and Centaurus and its northern end borders Cancer. It was included among the 48 constellations listed by the 2nd century astronomer Ptolemy. Commonly represented as a water snake, it straddles the celestial equator.
The Virgo Cluster is a large cluster of galaxies whose center is 53.8 ± 0.3 Mly away in the constellation Virgo. Comprising approximately 1,300 member galaxies, the cluster forms the heart of the larger Virgo Supercluster, of which the Local Group is a member. The Local Group actually experiences the mass of the Virgo Supercluster as the Virgocentric flow. It is estimated that the Virgo Cluster's mass is 1.2×1015M☉ out to 8 degrees of the cluster's center or a radius of about 2.2 Mpc.
Messier 87 is a supergiant elliptical galaxy in the constellation Virgo that contains several trillion stars. One of the largest and most massive galaxies in the local universe, it has a large population of globular clusters—about 15,000 compared with the 150–200 orbiting the Milky Way—and a jet of energetic plasma that originates at the core and extends at least 1,500 parsecs, traveling at a relativistic speed. It is one of the brightest radio sources in the sky and a popular target for both amateur and professional astronomers.
Messier 49 is a giant elliptical galaxy about 56 million light-years away in the equatorial constellation of Virgo. This galaxy was discovered by astronomer Charles Messier in 1777.
Messier 58 is an intermediate barred spiral galaxy with a weak inner ring structure located within the constellation Virgo, approximately 68 million light-years away from Earth. It was discovered by Charles Messier on April 15, 1779 and is one of four barred spiral galaxies that appear in Messier's catalogue. M58 is one of the brightest galaxies in the Virgo Cluster. From 1779 it was arguably the farthest known astronomical object until the release of the New General Catalogue in the 1880s and even more so the publishing of redshift values in the 1920s.
A dwarf galaxy is a small galaxy composed of about 1000 up to several billion stars, as compared to the Milky Way's 200–400 billion stars. The Large Magellanic Cloud, which closely orbits the Milky Way and contains over 30 billion stars, is sometimes classified as a dwarf galaxy; others consider it a full-fledged galaxy. Dwarf galaxies' formation and activity are thought to be heavily influenced by interactions with larger galaxies. Astronomers identify numerous types of dwarf galaxies, based on their shape and composition.
Messier 84 or M84, also known as NGC 4374, is a giant elliptical or lenticular galaxy in the constellation Virgo. Charles Messier discovered the object in 1781 in a systematic search for "nebulous objects" in the night sky. It is the 84th object in the Messier Catalogue and in the heavily populated core of the Virgo Cluster of galaxies, part of the local supercluster.
Messier 88 is a spiral galaxy about 50 to 60 million light-years away from Earth in the constellation Coma Berenices. It was discovered by Charles Messier in 1781.
Messier 89 is an elliptical galaxy in the constellation Virgo. It was discovered by Charles Messier on March 18, 1781. M89 is a member of the Virgo Cluster of galaxies.
Messier 90 is an intermediate spiral galaxy exhibiting a weak inner ring structure about 60 million light-years away[a] in the constellation Virgo. It was discovered by Charles Messier in 1781.
The Spring Triangle is an astronomical asterism involving an imaginary triangle drawn upon the celestial sphere, with its defining vertices at Arcturus, Spica, and Regulus. This triangle connects the constellations of Boötes, Virgo, and Leo. It is visible in the evening rising in the southeastern sky of the Northern Hemisphere between March and May and setting until August, while at morning rising and setting from November to the end of February.
NGC 4889 is an E4 supergiant elliptical galaxy. It was discovered in 1785 by the British astronomer Frederick William Herschel I, who catalogued it as a bright, nebulous patch. The brightest galaxy within the northern Coma Cluster, it is located at a median distance of 94 million parsecs from Earth. At the core of the galaxy is a supermassive black hole that heats the intracluster medium through the action of friction from infalling gases and dust. The gamma ray bursts from the galaxy extend out to several million light years of the cluster.
NGC 4473 is an elliptical galaxy located about 50 million light-years away in the constellation of Coma Berenices. It was discovered by astronomer William Herschel on April 8, 1784. NGC 4473 has an inclination of about 71°. NGC 4473 is a member of a chain of galaxies called Markarian's Chain which is part of the larger Virgo Cluster of galaxies.
NGC 4478 is an elliptical galaxy located about 50 million light-years away in the constellation Virgo. NGC 4478 was discovered by astronomer William Herschel on April 12, 1784. NGC 4478 is a member of the Virgo Cluster.