An Etymological Dictionary of Astronomy and Astrophysics
English-French-Persian

The Maiden. A large constellation of the Zodiac, situated at the celestial equator with 13h right ascension, 2° south declination. The brightest star is the first magnitude → Spica, and there are seven others brighter than fourth magnitude. Because of the presence of a background galaxy cluster, → Virgo cluster, this constellation is especially rich in galaxies. Eleven of the brighter galaxies are listed in the → Messier catalog. Abbreviation: Vir; Genitive: Virginis.

L. virgo "maiden, unwedded girl or woman."

Dušizé "maiden, virgin;" Mid.Pers. dôšizag "maiden, virgin," related to duxtar, duxt "daughter" (O.Pers. *duxçi-; Av. dugədar-, duγdar-; cf. Skt. duhitár-, Gk. thygater; E. daughter; Ger. Tochter; PIE base *dhug(h)əter-); Manichean Mid.Pers. duxš "princess, girl of noble birth;" O.Pers. duxši- (Elamite du-uk-ši-iš) "royal princess" + diminutive suffix -izag, -izé (as in suffixed Fr. demoiselle, from V.L. *dominicella, from domin(a) "lady" + -i- + -cella diminutive suffix).

The most powerful radio source in the constellation Virgo, among the thousands of galactic systems comprising the → Virgo Cluster. Optically, it is an elliptical galaxy (M87) with a luminous blue jet about 1500 pc long. It is also an X-ray source (3C 274, Virgo X-1, 2U 1228+12).

→ Virgo.

The largest and nearest galaxy cluster to the Local Group. The Virgo cluster spans 120 square degrees on the sky and contains on the order of 2,000 galaxies. It is located at a distance of about 60 million light-years. It is an irregular cluster with no central concentration. The giant elliptical galaxy M87 is the most massive in the cluster.

→ Virgo; → cluster.

A → Michelson interferometer using → laser beams designed to detect → gravitational waves. It consists of two 3-km-long arms, which house the various machinery required to form a → laser interferometer. The gravitational waves searched for have frequencies between 10 Hz and 10 kHz. Virgo has been designed and built by a collaboration between the French Centre National de la Recherche Scientifique (CNRS) and the Italian Istituto Nazionale di Fisica Nucleare (INFN). It is now operated and improved in Cascina, a small town near Pisa on the site of the European Gravitational Observatory (EGO), by an international collaboration of scientists from France, Italy, the Netherlands, Poland, and Hungary. The initial Virgo detector observed the sky between 2007 and 2011 together with the two interferometers of the → Laser Interferometer Gravitational-Wave Observatory (LIGO), located in the United States. Virgo underwent a major upgrade after a long shutdown period. The "Advanced Virgo" overhaul lasted 5-year and costed 23 million Euros. The upgraded observatory was inaugurated on 20 February 2017 and, notably, detected the → GW170817 event.

Named after the → Virgo cluster of galaxies whose stellar explosions it aims to detect; → interferometer.

The irregular supercluster that contains the Virgo cluster and the Local Group. At least 100 galaxy groups and clusters are located within its diameter of 110 million light-years. It is one of millions of superclusters in the observable Universe.

→ Virgo; → supercluster.