Jupiter is the fifth planet from the Sun and the largest in the Solar System. It is a giant planet with a mass one-thousandth that of the Sun, but two-and-a-half times that of all the other planets in the Solar System combined. Jupiter and Saturn are gas giants; the other two giant planets, Uranus and Neptune are ice giants. Jupiter has been known to astronomers since antiquity. The Romans named it after their god Jupiter. Primarily composed of hydrogen with a quarter of its mass being helium, though helium comprises only about a tenth of the number of molecules. It may also have a rocky core of heavier elements, but like the other giant planets, Jupiter lacks a well-defined solid surface. The outer atmosphere is visibly segregated into several bands at different latitudes and a prominent result is the Great Red Spot, a giant storm that is known to have existed since at least the 17th century when it was first seen by telescope.
Surrounding Jupiter is a faint planetary ring system and a powerful magnetosphere. Jupiter has at least 69 moons, including the four large Galilean moons discovered by Galileo Galilei in 1610.
The cosmic voice of Jupiter
(NASA Voyager recording)
The Latin name Iuppiter originated as a vocative compound of the Old Latin vocative Iou and pater (father) and came to replace the Old Latin nominative case Ious. Jove is a less common English formation based on Iov, the stem of oblique cases of the Latin name. Linguistic studies identify the form Iou-pater as deriving from the Indo-European vocative compound Dyēu-pəter (meaning “O Father Sky-god“). Jupiter is the god of the sky and thunder and king of the gods in Ancient Roman religion and mythology. Was the chief deity of Roman state religion throughout the Republican and Imperial eras, until Christianity became the dominant religion of the Empire. In Roman mythology, he negotiates with Numa Pompilius, the second king of Rome, to establish principles of Roman religion such as offering, or sacrifice.
The Romans regarded Jupiter as the equivalent of the Greek Zeus (Ζεύς) and in Latin literature and Roman art, the myths and iconography of Zeus are adapted under the name Iuppiter, also referred to as Dias (Δίας). In the Greek-influenced tradition, Jupiter was the brother of Neptune and Pluto, the Roman equivalents of Poseidon and Hades respectively. Each presided over one of the three realms of the universe: sky, the waters, and the underworld.
Sacrificial victims (hostiae) offered to Jupiter were the ox (castrated bull), the lamb (on the Ides, the ovis idulis) and the wether (on the Ides of January). The animals were required to be white. The question of the lamb’s gender is unresolved; while a lamb is generally male, for the vintage-opening festival the flamen Dialis sacrificed a ewe. This rule seems to have had many exceptions, as the sacrifice of a ram on the Nundinae by the flaminica Dialis demonstrates.
During one of the crises of the Punic Wars, Jupiter was offered every animal born that year.
Those whom Jupiter wants to destroy, he first makes mad.
Gustav Holst – Jupiter, the Bringer of Jollity
Marcus Terentius Varro and Verrius Flaccus were the main sources on the theology of Jupiter and archaic Roman religion in general. Varro was acquainted with the libri pontificum (“books of the Pontiffs”) and their archaic classifications. On these two sources depend other ancient authorities, such as Ovid, Servius, Aulus Gellius, Macrobius, patristic texts, Dionysius of Halicarnassus and Plutarch. One of the most important sources which preserve the theology of Jupiter and other Roman deities is The City of God against the Pagans by Augustine of Hippo. Augustine’s criticism of traditional Roman religion is based on Varro’s lost work, Antiquitates Rerum Divinarum. Although a work of Christian apologetics, The City of God provides glimpses into Varro’s theological system and authentic Roman theological lore in general.
Io, Europa, Ganimedes puer, atque Calisto lascivo nimium perplacuere Iovi.
Georg Wissowa stressed Jupiter’s uniqueness as the only case among Indo-European religions in which the original god preserved his name, his identity and his prerogatives. In this view, Jupiter is the god of heaven and retains his identification with the sky among the Latin poets (his name is used as a synonym for “sky”).