title: Sculpture content: as the Gundestrup cauldron from the European Iron Age and the Bronze Age Trundholm sun chariot. The Protoliterate period in Mesopotamia, dominated by Uruk, saw the production of sophisticated works like the Warka Vase and cylinder seals. The Guennol Lioness is an outstanding small limestone figure from Elam of about 3000–2800 BCE, part human and part lioness. A little later there are a number of figures of large-eyed priests and worshippers, mostly in alabaster and up to a foot high, who attended temple cult images of the deity, but very few of these have survived. Sculptures from the Sumerian and


title: Sculpture content: Akkadian period generally had large, staring eyes, and long beards on the men. Many masterpieces have also been found at the Royal Cemetery at Ur (c. 2650 BCE), including the two figures of a "Ram in a Thicket", the "Copper Bull" and a bull's head on one of the Lyres of Ur. From the many subsequent periods before the ascendency of the Neo-Assyrian Empire in the 10th century BCE Mesopotamian art survives in a number of forms: cylinder seals, relatively small figures in the round, and reliefs of various sizes, including cheap plaques of moulded pottery for the home, some


title: Sculpture content: religious and some apparently not. The Burney Relief is an unusually elaborate and relatively large (20 x 15 inches, 50 x 37 cm) terracotta plaque of a naked winged goddess with the feet of a bird of prey, and attendant owls and lions. It comes from the 18th or 19th centuries BCE, and may also be moulded. Stone stelae, votive offerings, or ones probably commemorating victories and showing feasts, are also found from temples, which unlike more official ones lack inscriptions that would explain them; the fragmentary Stele of the Vultures is an early example of the inscribed type, and


title: Sculpture content: the Assyrian Black Obelisk of Shalmaneser III a large and solid late one. The conquest of the whole of Mesopotamia and much surrounding territory by the Assyrians created a larger and wealthier state than the region had known before, and very grandiose art in palaces and public places, no doubt partly intended to match the splendour of the art of the neighbouring Egyptian empire. Unlike earlier states, the Assyrians could use easily carved stone from northern Iraq, and did so in great quantity. The Assyrians developed a style of extremely large schemes of very finely detailed narrative low reliefs in


title: Sculpture content: stone for palaces, with scenes of war or hunting; the British Museum has an outstanding collection, including the "Lion Hunt of Ashurbanipal" and the Lachish reliefs showing a campaign. They produced very little sculpture in the round, except for colossal guardian figures of the human-headed lamassu, which are sculpted in high relief on two sides of a rectangular block, with the heads effectively in the round (and also five legs, so that both views seem complete). Even before dominating the region they had continued the cylinder seal tradition with designs which are often exceptionally energetic and refined. The monumental sculpture


title: Sculpture content: of ancient Egypt is world-famous, but refined and delicate small works exist in much greater numbers. The Egyptians used the distinctive technique of sunk relief, which is well suited to very bright sunlight. The main figures in reliefs adhere to the same figure convention as in painting, with parted legs (where not seated) and head shown from the side, but the torso from the front, and a standard set of proportions making up the figure, using 18 "fists" to go from the ground to the hair-line on the forehead. This appears as early as the Narmer Palette from Dynasty I.


title: Sculpture content: However, there as elsewhere the convention is not used for minor figures shown engaged in some activity, such as the captives and corpses. Other conventions make statues of males darker than females ones. Very conventionalized portrait statues appear from as early as Dynasty II, before 2,780 BCE, and with the exception of the art of the Amarna period of Ahkenaten, and some other periods such as Dynasty XII, the idealized features of rulers, like other Egyptian artistic conventions, changed little until after the Greek conquest. Egyptian pharaohs were always regarded as deities, but other deities are much less common in


title: Sculpture content: large statues, except when they represent the pharaoh "as" another deity; however the other deities are frequently shown in paintings and reliefs. The famous row of four colossal statues outside the main temple at Abu Simbel each show Rameses II, a typical scheme, though here exceptionally large. Small figures of deities, or their animal personifications, are very common, and found in popular materials such as pottery. Most larger sculpture survives from Egyptian temples or tombs; by Dynasty IV (2680–2565 BCE) at the latest the idea of the Ka statue was firmly established. These were put in tombs as a resting


title: Sculpture content: place for the "ka" portion of the soul, and so we have a good number of less conventionalized statues of well-off administrators and their wives, many in wood as Egypt is one of the few places in the world where the climate allows wood to survive over millennia. The so-called reserve heads, plain hairless heads, are especially naturalistic. Early tombs also contained small models of the slaves, animals, buildings and objects such as boats necessary for the deceased to continue his lifestyle in the afterworld, and later "Ushabti" figures. The first distinctive style of ancient Greek sculpture developed in the


title: Sculpture content: Early Bronze Age Cycladic period (3rd millennium BCE), where marble figures, usually female and small, are represented in an elegantly simplified geometrical style. Most typical is a standing pose with arms crossed in front, but other figures are shown in different poses, including a complicated figure of a harpist seated on a chair. The subsequent Minoan and Mycenaean cultures developed sculpture further, under influence from Syria and elsewhere, but it is in the later Archaic period from around 650 BCE that the kouros developed. These are large standing statues of naked youths, found in temples and tombs, with the kore


title: Sculpture content: as the clothed female equivalent, with elaborately dressed hair; both have the "archaic smile". They seem to have served a number of functions, perhaps sometimes representing deities and sometimes the person buried in a grave, as with the Kroisos Kouros. They are clearly influenced by Egyptian and Syrian styles, but the Greek artists were much more ready to experiment within the style. During the 6th century Greek sculpture developed rapidly, becoming more naturalistic, and with much more active and varied figure poses in narrative scenes, though still within idealized conventions. Sculptured pediments were added to temples, including the Parthenon in


title: Sculpture content: Athens, where the remains of the pediment of around 520 using figures in the round were fortunately used as infill for new buildings after the Persian sack in 480 BCE, and recovered from the 1880s on in fresh unweathered condition. Other significant remains of architectural sculpture come from Paestum in Italy, Corfu, Delphi and the Temple of Aphaea in Aegina (much now in Munich). Most Greek sculpture originally included at least some colour; the Ny Carlsberg Glyptotek Museum in Copenhagen, Denmark, has done extensive research and recreation of the original colours. There are fewer original remains from the first phase


title: Sculpture content: of the Classical period, often called the Severe style; free-standing statues were now mostly made in bronze, which always had value as scrap. The Severe style lasted from around 500 in reliefs, and soon after 480 in statues, to about 450. The relatively rigid poses of figures relaxed, and asymmetrical turning positions and oblique views became common, and deliberately sought. This was combined with a better understanding of anatomy and the harmonious structure of sculpted figures, and the pursuit of naturalistic representation as an aim, which had not been present before. Excavations at the Temple of Zeus, Olympia since 1829


title: Sculpture content: have revealed the largest group of remains, from about 460, of which many are in the Louvre. The "High Classical" period lasted only a few decades from about 450 to 400, but has had a momentous influence on art, and retains a special prestige, despite a very restricted number of original survivals. The best known works are the Parthenon Marbles, traditionally (since Plutarch) executed by a team led by the most famous ancient Greek sculptor Phidias, active from about 465–425, who was in his own day more famous for his colossal chryselephantine Statue of Zeus at Olympia (c. 432), one


title: Sculpture content: of the Seven Wonders of the Ancient World, his "Athena Parthenos" (438), the cult image of the Parthenon, and "Athena Promachos", a colossal bronze figure that stood next to the Parthenon; all of these are lost but are known from many representations. He is also credited as the creator of some life-size bronze statues known only from later copies whose identification is controversial, including the "Ludovisi Hermes". The High Classical style continued to develop realism and sophistication in the human figure, and improved the depiction of drapery (clothes), using it to add to the impact of active poses. Facial expressions


title: Sculpture content: were usually very restrained, even in combat scenes. The composition of groups of figures in reliefs and on pediments combined complexity and harmony in a way that had a permanent influence on Western art. Relief could be very high indeed, as in the Parthenon illustration below, where most of the leg of the warrior is completely detached from the background, as were the missing parts; relief this high made sculptures more subject to damage. The Late Classical style developed the free-standing female nude statue, supposedly an innovation of Praxiteles, and developed increasingly complex and subtle poses that were interesting when


title: Sculpture content: viewed from a number of angles, as well as more expressive faces; both trends were to be taken much further in the Hellenistic period. The Hellenistic period is conventionally dated from the death of Alexander the Great in 323 BCE, and ending either with the final conquest of the Greek heartlands by Rome in 146 BCE or with the final defeat of the last remaining successor-state to Alexander's empire after the Battle of Actium in 31 BCE, which also marks the end of Republican Rome. It is thus much longer than the previous periods, and includes at least two major


title: Sculpture content: phases: a "Pergamene" style of experimentation, exuberance and some sentimentality and vulgarity, and in the 2nd century BCE a classicising return to a more austere simplicity and elegance; beyond such generalizations dating is typically very uncertain, especially when only later copies are known, as is usually the case. The initial Pergamene style was not especially associated with Pergamon, from which it takes its name, but the very wealthy kings of that state were among the first to collect and also copy Classical sculpture, and also commissioned much new work, including the famous Pergamon Altar whose sculpture is now mostly in


title: Sculpture content: Berlin and which exemplifies the new style, as do the Mausoleum at Halicarnassus (another of the Seven Wonders), the famous "Laocoön and his Sons" in the Vatican Museums, a late example, and the bronze original of "The Dying Gaul" (illustrated at top), which we know was part of a group actually commissioned for Pergamon in about 228 BCE, from which the Ludovisi Gaul was also a copy. The group called the Farnese Bull, possibly a 2nd-century marble original, is still larger and more complex, Hellenistic sculpture greatly expanded the range of subjects represented, partly as a result of greater general


title: Sculpture content: prosperity, and the emergence of a very wealthy class who had large houses decorated with sculpture, although we know that some examples of subjects that seem best suited to the home, such as children with animals, were in fact placed in temples or other public places. For a much more popular home decoration market there were Tanagra figurines, and those from other centres where small pottery figures were produced on an industrial scale, some religious but others showing animals and elegantly dressed ladies. Sculptors became more technically skilled in representing facial expressions conveying a wide variety of emotions and the


title: Sculpture content: portraiture of individuals, as well representing different ages and races. The reliefs from the Mausoleum are rather atypical in that respect; most work was free-standing, and group compositions with several figures to be seen in the round, like the "Laocoon" and the Pergamon group celebrating victory over the Gauls became popular, having been rare before. The Barberini Faun, showing a satyr sprawled asleep, presumably after drink, is an example of the moral relaxation of the period, and the readiness to create large and expensive sculptures of subjects that fall short of the heroic. After the conquests of Alexander Hellenistic culture


title: Sculpture content: was dominant in the courts of most of the Near East, and some of Central Asia, and increasingly being adopted by European elites, especially in Italy, where Greek colonies initially controlled most of the South. Hellenistic art, and artists, spread very widely, and was especially influential in the expanding Roman Republic and when it encountered Buddhism in the easternmost extensions of the Hellenistic area. The massive so-called Alexander Sarcophagus found in Sidon in modern Lebanon, was probably made there at the start of the period by expatriate Greek artists for a Hellenized Persian governor. The wealth of the period led


title: Sculpture content: to a greatly increased production of luxury forms of small sculpture, including engraved gems and cameos, jewellery, and gold and silverware. Early Roman art was influenced by the art of Greece and that of the neighbouring Etruscans, themselves greatly influenced by their Greek trading partners. An Etruscan speciality was near life size tomb effigies in terracotta, usually lying on top of a sarcophagus lid propped up on one elbow in the pose of a diner in that period. As the expanding Roman Republic began to conquer Greek territory, at first in Southern Italy and then the entire Hellenistic world except


title: Sculpture content: for the Parthian far east, official and patrician sculpture became largely an extension of the Hellenistic style, from which specifically Roman elements are hard to disentangle, especially as so much Greek sculpture survives only in copies of the Roman period. By the 2nd century BCE, "most of the sculptors working at Rome" were Greek, often enslaved in conquests such as that of Corinth (146 BCE), and sculptors continued to be mostly Greeks, often slaves, whose names are very rarely recorded. Vast numbers of Greek statues were imported to Rome, whether as booty or the result of extortion or commerce, and


title: Sculpture content: temples were often decorated with re-used Greek works. A native Italian style can be seen in the tomb monuments, which very often featured portrait busts, of prosperous middle-class Romans, and portraiture is arguably the main strength of Roman sculpture. There are no survivals from the tradition of masks of ancestors that were worn in processions at the funerals of the great families and otherwise displayed in the home, but many of the busts that survive must represent ancestral figures, perhaps from the large family tombs like the Tomb of the Scipios or the later mausolea outside the city. The famous


title: Sculpture content: bronze head supposedly of Lucius Junius Brutus is very variously dated, but taken as a very rare survival of Italic style under the Republic, in the preferred medium of bronze. Similarly stern and forceful heads are seen on coins of the Late Republic, and in the Imperial period coins as well as busts sent around the Empire to be placed in the basilicas of provincial cities were the main visual form of imperial propaganda; even Londinium had a near-colossal statue of Nero, though far smaller than the 30 metre high Colossus of Nero in Rome, now lost. The Romans did


title: Sculpture content: not generally attempt to compete with free-standing Greek works of heroic exploits from history or mythology, but from early on produced historical works in relief, culminating in the great Roman triumphal columns with continuous narrative reliefs winding around them, of which those commemorating Trajan (CE 113) and Marcus Aurelius (by 193) survive in Rome, where the Ara Pacis ("Altar of Peace", 13 BCE) represents the official Greco-Roman style at its most classical and refined. Among other major examples are the earlier re-used reliefs on the Arch of Constantine and the base of the Column of Antoninus Pius (161), Campana reliefs


title: Sculpture content: were cheaper pottery versions of marble reliefs and the taste for relief was from the imperial period expanded to the sarcophagus. All forms of luxury small sculpture continued to be patronized, and quality could be extremely high, as in the silver Warren Cup, glass Lycurgus Cup, and large cameos like the Gemma Augustea, Gonzaga Cameo and the "Great Cameo of France". For a much wider section of the population, moulded relief decoration of pottery vessels and small figurines were produced in great quantity and often considerable quality. After moving through a late 2nd-century "baroque" phase, in the 3rd century, Roman


title: Sculpture content: art largely abandoned, or simply became unable to produce, sculpture in the classical tradition, a change whose causes remain much discussed. Even the most important imperial monuments now showed stumpy, large-eyed figures in a harsh frontal style, in simple compositions emphasizing power at the expense of grace. The contrast is famously illustrated in the Arch of Constantine of 315 in Rome, which combines sections in the new style with roundels in the earlier full Greco-Roman style taken from elsewhere, and the "Four Tetrarchs" (c. 305) from the new capital of Constantinople, now in Venice. Ernst Kitzinger found in both monuments


title: Sculpture content: the same "stubby proportions, angular movements, an ordering of parts through symmetry and repetition and a rendering of features and drapery folds through incisions rather than modelling... The hallmark of the style wherever it appears consists of an emphatic hardness, heaviness and angularity—in short, an almost complete rejection of the classical tradition". This revolution in style shortly preceded the period in which Christianity was adopted by the Roman state and the great majority of the people, leading to the end of large religious sculpture, with large statues now only used for emperors. However, rich Christians continued to commission reliefs for


title: Sculpture content: sarcophagi, as in the Sarcophagus of Junius Bassus, and very small sculpture, especially in ivory, was continued by Christians, building on the style of the consular diptych. The Early Christians were opposed to monumental religious sculpture, though continuing Roman traditions in portrait busts and sarcophagus reliefs, as well as smaller objects such as the consular diptych. Such objects, often in valuable materials, were also the main sculptural traditions (as far as is known) of the barbaric civilizations of the Migration period, as seen in the objects found in the 6th-century burial treasure at Sutton Hoo, and the jewellery of Scythian


title: Sculpture content: art and the hybrid Christian and animal style productions of Insular art. Following the continuing Byzantine tradition, Carolingian art revived ivory carving, often in panels for the treasure bindings of grand illuminated manuscripts, as well as crozier heads and other small fittings. Byzantine art, though producing superb ivory reliefs and architectural decorative carving, never returned to monumental sculpture, or even much small sculpture in the round. However, in the West during the Carolingian and Ottonian periods there was the beginnings of a production of monumental statues, in courts and major churches. This gradually spread; by the late 10th and 11th


title: Sculpture content: century there are records of several apparently life-size sculptures in Anglo-Saxon churches, probably of precious metal around a wooden frame, like the Golden Madonna of Essen. No Anglo-Saxon example has survived, and survivals of large non-architectural sculpture from before 1,000 are exceptionally rare. Much the finest is the Gero Cross, of 965–970, which is a crucifix, which was evidently the commonest type of sculpture; Charlemagne had set one up in the Palatine Chapel in Aachen around 800. These continued to grow in popularity, especially in Germany and Italy. The rune stones of the Nordic world, the Pictish stones of Scotland


title: Sculpture content: and possibly the high cross reliefs of Christian Great Britain, were northern sculptural traditions that bridged the period of Christianization. From about 1000 there was a general rebirth of artistic production in all Europe, led by general economic growth in production and commerce, and the new style of Romanesque art was the first medieval style to be used in the whole of Western Europe. The new cathedrals and pilgrim's churches were increasingly decorated with architectural stone reliefs, and new focuses for sculpture developed, such as the tympanum over church doors in the 12th century, and the inhabited capital with figures


title: Sculpture content: and often narrative scenes. Outstanding abbey churches with sculpture include in France Vézelay and Moissac and in Spain Silos. Romanesque art was characterised by a very vigorous style in both sculpture and painting. The capitals of columns were never more exciting than in this period, when they were often carved with complete scenes with several figures. The large wooden crucifix was a German innovation right at the start of the period, as were free-standing statues of the enthroned Madonna, but the high relief was above all the sculptural mode of the period. Compositions usually had little depth, and needed to


title: Sculpture content: be flexible to squeeze themselves into the shapes of capitals, and church typanums; the tension between a tightly enclosing frame, from which the composition sometimes escapes, is a recurrent theme in Romanesque art. Figures still often varied in size in relation to their importance portraiture hardly existed. Objects in precious materials such as ivory and metal had a very high status in the period, much more so than monumental sculpture — we know the names of more makers of these than painters, illuminators or architect-masons. Metalwork, including decoration in enamel, became very sophisticated, and many spectacular shrines made to hold


title: Sculpture content: relics have survived, of which the best known is the Shrine of the Three Kings at Cologne Cathedral by Nicholas of Verdun. The bronze Gloucester candlestick and the brass font of 1108–17 now in Liège are superb examples, very different in style, of metal casting, the former highly intricate and energetic, drawing on manuscript painting, while the font shows the Mosan style at its most classical and majestic. The bronze doors, a triumphal column and other fittings at Hildesheim Cathedral, the Gniezno Doors, and the doors of the Basilica di San Zeno in Verona are other substantial survivals. The aquamanile,


title: Sculpture content: a container for water to wash with, appears to have been introduced to Europe in the 11th century, and often took fantastic zoomorphic forms; surviving examples are mostly in brass. Many wax impressions from impressive seals survive on charters and documents, although Romanesque coins are generally not of great aesthetic interest. The Cloisters Cross is an unusually large ivory crucifix, with complex carving including many figures of prophets and others, which has been attributed to one of the relatively few artists whose name is known, Master Hugo, who also illuminated manuscripts. Like many pieces it was originally partly coloured. The


title: Sculpture content: Lewis chessmen are well-preserved examples of small ivories, of which many pieces or fragments remain from croziers, plaques, pectoral crosses and similar objects. The Gothic period is essentially defined by Gothic architecture, and does not entirely fit with the development of style in sculpture in either its start or finish. The facades of large churches, especially around doors, continued to have large typanums, but also rows of sculpted figures spreading around them. The statues on the Western (Royal) Portal at Chartres Cathedral (c. 1145) show an elegant but exaggerated columnar elongation, but those on the south transept portal, from 1215


title: Sculpture content: to 1220, show a more naturalistic style and increasing detachment from the wall behind, and some awareness of the classical tradition. These trends were continued in the west portal at Rheims Cathedral of a few years later, where the figures are almost in the round, as became usual as Gothic spread across Europe. In Italy Nicola Pisano (1258–1278) and his son Giovanni developed a style that is often called Proto-Renaissance, with unmistakable influence from Roman sarcophagi and sophisticated and crowded compositions, including a sympathetic handling of nudity, in relief panels on their pulpit of Siena Cathedral (1265–68), the Fontana Maggiore


title: Sculpture content: in Perugia, and Giovanni's pulpit in Pistoia of 1301. Another revival of classical style is seen in the International Gothic work of Claus Sluter and his followers in Burgundy and Flanders around 1400. Late Gothic sculpture continued in the North, with a fashion for very large wooden sculpted altarpieces with increasingly virtuoso carving and large numbers agitated expressive figures; most surviving examples are in Germany, after much iconoclasm elsewhere. Tilman Riemenschneider, Veit Stoss and others continued the style well into the 16th century, gradually absorbing Italian Renaissance influences. Life-size tomb effigies in stone or alabaster became popular for the wealthy,


title: Sculpture content: and grand multi-level tombs evolved, with the Scaliger Tombs of Verona so large they had to be moved outside the church. By the 15th century there was an industry exporting Nottingham alabaster altar reliefs in groups of panels over much of Europe for economical parishes who could not afford stone retables. Small carvings, for a mainly lay and often female market, became a considerable industry in Paris and some other centres. Types of ivories included small devotional polyptychs, single figures, especially of the Virgin, mirror-cases, combs, and elaborate caskets with scenes from Romances, used as engagement presents. The very wealthy


title: Sculpture content: collected extravagantly elaborate jewelled and enamelled metalwork, both secular and religious, like the Duc de Berry's Holy Thorn Reliquary, until they ran short of money, when they were melted down again for cash. Renaissance sculpture proper is often taken to begin with the famous competition for the doors of the Florence Baptistry in 1403, from which the trial models submitted by the winner, Lorenzo Ghiberti, and Filippo Brunelleschi survive. Ghiberti's doors are still in place, but were undoubtedly eclipsed by his second pair for the other entrance, the so-called "Gates of Paradise", which took him from 1425 to 1452, and


title: Sculpture content: are dazzlingly confident classicizing compositions with varied depths of relief allowing extensive backgrounds. The intervening years had seen Ghiberti's early assistant Donatello develop with seminal statues including his "Davids" in marble (1408–09) and bronze (1440s), and his Equestrian statue of Gattamelata, as well as reliefs. A leading figure in the later period was Andrea del Verrocchio, best known for his equestrian statue of Bartolomeo Colleoni in Venice; his pupil Leonardo da Vinci designed an equine sculpture in 1482 "The Horse" for Milan-but only succeeded in making a clay model which was destroyed by French archers in 1499, and his other


title: Sculpture content: ambitious sculptural plans were never completed. The period was marked by a great increase in patronage of sculpture by the state for public art and by the wealthy for their homes; especially in Italy, public sculpture remains a crucial element in the appearance of historic city centres. Church sculpture mostly moved inside just as outside public monuments became common. Portrait sculpture, usually in busts, became popular in Italy around 1450, with the Neapolitan Francesco Laurana specializing in young women in meditative poses, while Antonio Rossellino and others more often depicted knobbly-faced men of affairs, but also young children. The portrait


title: Sculpture content: medal invented by Pisanello also often depicted women; relief plaquettes were another new small form of sculpture in cast metal. Michelangelo was an active sculptor from about 1500 to 1520, and his great masterpieces including his "David", "Pietà", "Moses", and pieces for the Tomb of Pope Julius II and Medici Chapel could not be ignored by subsequent sculptors. His iconic David (1504) has a "contrapposto" pose, borrowed from classical sculpture. It differs from previous representations of the subject in that David is depicted before his battle with Goliath and not after the giant's defeat. Instead of being shown victorious, as


title: Sculpture content: Donatello and Verocchio had done, David looks tense and battle ready. As in painting, early Italian Mannerist sculpture was very largely an attempt to find an original style that would top the achievement of the High Renaissance, which in sculpture essentially meant Michelangelo, and much of the struggle to achieve this was played out in commissions to fill other places in the Piazza della Signoria in Florence, next to Michelangelo's "David". Baccio Bandinelli took over the project of "Hercules and Cacus" from the master himself, but it was little more popular than it is now, and maliciously compared by Benvenuto


title: Sculpture content: Cellini to "a sack of melons", though it had a long-lasting effect in apparently introducing relief panels on the pedestal of statues. Like other works of his and other Mannerists it removes far more of the original block than Michelangelo would have done. Cellini's bronze "Perseus with the head of Medusa" is certainly a masterpiece, designed with eight angles of view, another Mannerist characteristic, but is indeed mannered compared to the "David"s of Michelangelo and Donatello. Originally a goldsmith, his famous gold and enamel Salt Cellar (1543) was his first sculpture, and shows his talent at its best. As these


title: Sculpture content: examples show, the period extended the range of secular subjects for large works beyond portraits, with mythological figures especially favoured; previously these had mostly been found in small works. Small bronze figures for collector's cabinets, often mythological subjects with nudes, were a popular Renaissance form at which Giambologna, originally Flemish but based in Florence, excelled in the later part of the century, also creating life-size sculptures, of which two joined the collection in the Piazza della Signoria. He and his followers devised elegant elongated examples of the "figura serpentinata", often of two intertwined figures, that were interesting from all angles.


title: Sculpture content: In Baroque sculpture, groups of figures assumed new importance, and there was a dynamic movement and energy of human forms— they spiralled around an empty central vortex, or reached outwards into the surrounding space. Baroque sculpture often had multiple ideal viewing angles, and reflected a general continuation of the Renaissance move away from the relief to sculpture created in the round, and designed to be placed in the middle of a large space—elaborate fountains such as Bernini's Fontana dei Quattro Fiumi (Rome, 1651), or those in the Gardens of Versailles were a Baroque speciality. The Baroque style was perfectly suited


title: Sculpture content: to sculpture, with Gian Lorenzo Bernini the dominating figure of the age in works such as "The Ecstasy of St Theresa" (1647–1652). Much Baroque sculpture added extra-sculptural elements, for example, concealed lighting, or water fountains, or fused sculpture and architecture to create a transformative experience for the viewer. Artists saw themselves as in the classical tradition, but admired Hellenistic and later Roman sculpture, rather than that of the more "Classical" periods as they are seen today. The Protestant Reformation brought an almost total stop to religious sculpture in much of Northern Europe, and though secular sculpture, especially for portrait busts


title: Sculpture content: and tomb monuments, continued, the Dutch Golden Age has no significant sculptural component outside goldsmithing. Partly in direct reaction, sculpture was as prominent in Roman Catholicism as in the late Middle Ages. Statues of rulers and the nobility became increasingly popular. In the 18th century much sculpture continued on Baroque lines—the Trevi Fountain was only completed in 1762. Rococo style was better suited to smaller works, and arguably found its ideal sculptural form in early European porcelain, and interior decorative schemes in wood or plaster such as those in French domestic interiors and Austrian and Bavarian pilgrimage churches. The Neoclassical


title: Sculpture content: style that arrived in the late 18th century gave great emphasis to sculpture. Jean-Antoine Houdon exemplifies the penetrating portrait sculpture the style could produce, and Antonio Canova's nudes the idealist aspect of the movement. The Neoclassical period was one of the great ages of public sculpture, though its "classical" prototypes were more likely to be Roman copies of Hellenistic sculptures. In sculpture, the most familiar representatives are the Italian Antonio Canova, the Englishman John Flaxman and the Dane Bertel Thorvaldsen. The European neoclassical manner also took hold in the United States, where its pinnacle occurred somewhat later and is exemplified


title: Sculpture content: in the sculptures of Hiram Powers. Greco-Buddhist art is the artistic manifestation of Greco-Buddhism, a cultural syncretism between the Classical Greek culture and Buddhism, which developed over a period of close to 1000 years in Central Asia, between the conquests of Alexander the Great in the 4th century BCE, and the Islamic conquests of the 7th century CE. Greco-Buddhist art is characterized by the strong idealistic realism of Hellenistic art and the first representations of the Buddha in human form, which have helped define the artistic (and particularly, sculptural) canon for Buddhist art throughout the Asian continent up to the


title: Sculpture content: present. Though dating is uncertain, it appears that strongly Hellenistic styles lingered in the East for several centuries after they had declined around the Mediterranean, as late as the 5th century CE. Some aspects of Greek art were adopted while others did not spread beyond the Greco-Buddhist area; in particular the standing figure, often with a relaxed pose and one leg flexed, and the flying cupids or victories, who became popular across Asia as apsaras. Greek foliage decoration was also influential, with Indian versions of the Corinthian capital appearing. The origins of Greco-Buddhist art are to be found in the


title: Sculpture content: Hellenistic Greco-Bactrian kingdom (250–130 BCE), located in today’s Afghanistan, from which Hellenistic culture radiated into the Indian subcontinent with the establishment of the small Indo-Greek kingdom (180–10 BCE). Under the Indo-Greeks and then the Kushans, the interaction of Greek and Buddhist culture flourished in the area of Gandhara, in today’s northern Pakistan, before spreading further into India, influencing the art of Mathura, and then the Hindu art of the Gupta empire, which was to extend to the rest of South-East Asia. The influence of Greco-Buddhist art also spread northward towards Central Asia, strongly affecting the art of the Tarim Basin


title: Sculpture content: and the Dunhuang Caves, and ultimately the sculpted figure in China, Korea, and Japan. Chinese ritual bronzes from the Shang and Western Zhou Dynasties come from a period of over a thousand years from c. 1500 BCE, and have exerted a continuing influence over Chinese art. They are cast with complex patterned and zoomorphic decoration, but avoid the human figure, unlike the huge figures only recently discovered at Sanxingdui. The spectacular Terracotta Army was assembled for the tomb of Qin Shi Huang, the first emperor of a unified China from 221–210 BCE, as a grand imperial version of the figures


title: Sculpture content: long placed in tombs to enable the deceased to enjoy the same lifestyle in the afterlife as when alive, replacing actual sacrifices of very early periods. Smaller figures in pottery or wood were placed in tombs for many centuries afterwards, reaching a peak of quality in Tang dynasty tomb figures. The tradition of unusually large pottery figures persisted in China, through Tang sancai tomb figures to later Buddhist statues such as the near life-size set of Yixian glazed pottery luohans and later figures for temples and tombs. These came to replace earlier equivalents in wood. Native Chinese religions do not


title: Sculpture content: usually use cult images of deities, or even represent them, and large religious sculpture is nearly all Buddhist, dating mostly from the 4th to the 14th century, and initially using Greco-Buddhist models arriving via the Silk Road. Buddhism is also the context of all large portrait sculpture; in total contrast to some other areas, in medieval China even painted images of the emperor were regarded as private. Imperial tombs have spectacular avenues of approach lined with real and mythological animals on a scale matching Egypt, and smaller versions decorate temples and palaces. Small Buddhist figures and groups were produced to


title: Sculpture content: a very high quality in a range of media, as was relief decoration of all sorts of objects, especially in metalwork and jade. In the earlier periods, large quantities of sculpture were cut from the living rock in pilgrimage cave-complexes, and as outside rock reliefs. These were mostly originally painted. In notable contrast to literati painters, sculptors of all sorts were regarded as artisans and very few names are recorded. From the Ming dynasty onwards, statuettes of religious and secular figures were produced in Chinese porcelain and other media, which became an important export. Towards the end of the long


title: Sculpture content: Neolithic Jōmon period, some pottery vessels were "flame-rimmed" with extravagant extensions to the rim that can only be called sculptural, and very stylized pottery dogū figures were produced, many with the characteristic "snow-goggle" eyes. During the Kofun period of the 3rd to 6th century CE, haniwa terracotta figures of humans and animals in a simplistic style were erected outside important tombs. The arrival of Buddhism in the 6th century brought with it sophisticated traditions in sculpture, Chinese styles mediated via Korea. The 7th-century Hōryū-ji and its contents have survived more intact than any East Asian Buddhist temple of its date,


title: Sculpture content: with works including a "Shaka Trinity" of 623 in bronze, showing the historical Buddha flanked by two bodhisattvas and also the Guardian Kings of the Four Directions. The wooden image (9th century) of Shakyamuni, the "historic" Buddha, enshrined in a secondary building at the Murō-ji, is typical of the early Heian sculpture, with its ponderous body, covered by thick drapery folds carved in the hompa-shiki (rolling-wave) style, and its austere, withdrawn facial expression. The Kei school of sculptors, particularly Unkei, created a new, more realistic style of sculpture. Almost all subsequent significant large sculpture in Japan was Buddhist, with some


title: Sculpture content: Shinto equivalents, and after Buddhism declined in Japan in the 15th century, monumental sculpture became largely architectural decoration and less significant. However sculptural work in the decorative arts was developed to a remarkable level of technical achievement and refinement in small objects such as inro and netsuke in many materials, and metal "tosogu" or Japanese sword mountings. In the 19th century there were export industries of small bronze sculptures of extreme virtuosity, ivory and porcelain figurines, and other types of small sculpture, increasingly emphasizing technical accomplishment. The first known sculpture in the Indian subcontinent is from the Indus Valley civilization


title: Sculpture content: (3300–1700 BCE), found in sites at Mohenjo-daro and Harappa in modern-day Pakistan. These include the famous small bronze female dancer. However, such figures in bronze and stone are rare and greatly outnumbered by pottery figurines and stone seals, often of animals or deities very finely depicted. After the collapse of the Indus Valley civilization there is little record of sculpture until the Buddhist era, apart from a hoard of copper figures of (somewhat controversially) c. 1500 BCE from Daimabad. Thus the great tradition of Indian monumental sculpture in stone appears to begin, relative to other cultures, and the development of


title: Sculpture content: Indian civilization, relatively late, with the reign of Asoka from 270 to 232 BCE, and the Pillars of Ashoka he erected around India, carrying his edicts and topped by famous sculptures of animals, mostly lions, of which six survive. Large amounts of figurative sculpture, mostly in relief, survive from Early Buddhist pilgrimage stupas, above all Sanchi; these probably developed out of a tradition using wood that also embraced Hinduism. The pink sandstone Hindu, Jain and Buddhist sculptures of Mathura from the 1st to 3rd centuries CE reflected both native Indian traditions and the Western influences received through the Greco-Buddhist art


title: Sculpture content: of Gandhara, and effectively established the basis for subsequent Indian religious sculpture. The style was developed and diffused through most of India under the Gupta Empire (c. 320–550) which remains a "classical" period for Indian sculpture, covering the earlier Ellora Caves, though the Elephanta Caves are probably slightly later. Later large-scale sculpture remains almost exclusively religious, and generally rather conservative, often reverting to simple frontal standing poses for deities, though the attendant spirits such as apsaras and yakshi often have sensuously curving poses. Carving is often highly detailed, with an intricate backing behind the main figure in high relief. The


title: Sculpture content: celebrated bronzes of the Chola dynasty (c. 850–1250) from south India, many designed to be carried in processions, include the iconic form of Shiva as Nataraja, with the massive granite carvings of Mahabalipuram dating from the previous Pallava dynasty. The sculpture of the region tends to be characterised by a high degree of ornamentation, as seen in the great monuments of Hindu and Buddhist Khmer sculpture (9th to 13th centuries) at Angkor Wat and elsewhere, the enormous 9th-century Buddhist complex at Borobudur in Java, and the Hindu monuments of Bali. Both of these include many reliefs as well as figures


title: Sculpture content: in the round; Borobudur has 2,672 relief panels, 504 Buddha statues, many semi-concealed in openwork stupas, and many large guardian figures. In Thailand and Laos, sculpture was mainly of Buddha images, often gilded, both large for temples and monasteries, and small figurines for private homes. Traditional sculpture in Myanmar emerged before the Bagan period. As elsewhere in the region, most of the wood sculptures of the Bagan and Ava periods have been lost. In later periods Chinese influence predominated in Vietnam, Laos and Cambodia, and more wooden sculpture survives from across the region. Islam is famously aniconic, so the vast


title: Sculpture content: majority of sculpture is arabesque decoration in relief or openwork, based on vegetable motifs, but tending to geometrical abstract forms. In the very early Mshatta Facade (740s), now mostly in Berlin, there are animals within the dense arabesques in high relief, and figures of animals and men in mostly low relief are found in conjunction with decoration on many later pieces in various materials, including metalwork, ivory and ceramics. Figures of animals in the round were often acceptable for works used in private contexts if the object was clearly practical, so medieval Islamic art contains many metal animals that are


title: Sculpture content: aquamaniles, incense burners or supporters for fountains, as in the stone lions supporting the famous one in the Alhambra, culminating in the largest medieval Islamic animal figure known, the Pisa Griffin. In the same way, luxury hardstone carvings such as dagger hilts and cups may be formed as animals, especially in Mughal art. The degree of acceptability of such relaxations of strict Islamic rules varies between periods and regions, with Islamic Spain, Persia and India often leading relaxation, and is typically highest in courtly contexts. Historically, with the exception of some monumental Egyptian sculpture, most African sculpture was created in


title: Sculpture content: wood and other organic materials that have not survived from earlier than a few centuries ago; older pottery figures are found from a number of areas. Masks are important elements in the art of many peoples, along with human figures, often highly stylized. There is a vast variety of styles, often varying within the same context of origin depending on the use of the object, but wide regional trends are apparent; sculpture is most common among "groups of settled cultivators in the areas drained by the Niger and Congo rivers" in West Africa. Direct images of deities are relatively infrequent,


title: Sculpture content: but masks in particular are or were often made for religious ceremonies; today many are made for tourists as "airport art". African masks were an influence on European Modernist art, which was inspired by their lack of concern for naturalistic depiction. The Nubian Kingdom of Kush in modern Sudan was in close and often hostile contact with Egypt, and produced monumental sculpture mostly derivative of styles to the north. In West Africa, the earliest known sculptures are from the Nok culture which thrived between 500 BCE and 500 CE in modern Nigeria, with clay figures typically with elongated bodies and


title: Sculpture content: angular shapes. Later West African cultures developed bronze casting for reliefs to decorate palaces like the famous Benin Bronzes, and very fine naturalistic royal heads from around the Yoruba town of Ife in terracotta and metal from the 12th–14th centuries. Akan goldweights are a form of small metal sculptures produced over the period 1400–1900, some apparently representing proverbs and so with a narrative element rare in African sculpture, and royal regalia included impressive gold sculptured elements. Many West African figures are used in religious rituals and are often coated with materials placed on them for ceremonial offerings. The Mande-speaking peoples


title: Sculpture content: of the same region make pieces of wood with broad, flat surfaces and arms and legs are shaped like cylinders. In Central Africa, however, the main distinguishing characteristics include heart-shaped faces that are curved inward and display patterns of circles and dots. Populations in the African Great Lakes are not known for their sculpture. However, one style from the region is pole sculptures, carved in human shapes and decorated with geometric forms, while the tops are carved with figures of animals, people, and various objects. These poles are, then, placed next to graves and are associated with death and the


title: Sculpture content: ancestral world. The culture known from Great Zimbabwe left more impressive buildings than sculpture but the eight soapstone Zimbabwe Birds appear to have had a special significance and were mounted on monoliths. Modern Zimbabwean sculptors in soapstone have achieved considerable international success. Southern Africa’s oldest known clay figures date from 400 to 600 CE and have cylindrical heads with a mixture of human and animal features. The creation of sculptures in Ethiopia and Eritrea can be traced back to its ancient past with the kingdoms of Dʿmt and Aksum. Christian art was established in Ethiopia with the conversion from paganism


title: Sculpture content: to Christianity in the 4th century CE, during the reign of king Ezana of Axum. Christian imagery decorated churches during the Asksumite period and later eras. For instance, at Lalibela, life-size saints were carved into the Church of Bet Golgotha; by tradition these were made during the reign of the Zagwe ruler Gebre Mesqel Lalibela in the 12th century, but they were more likely crafted in the 15th century during the Solomonic dynasty. However, the Church of Saint George, Lalibela, one of several examples of rock cut architecture at Lalibela containing intricate carvings, was built in the 10th–13th centuries as


title: Sculpture content: proven by archaeology. In ancient Sudan, the development of sculpture stretches from the simple pottery of the Kerma culture beginning around 2500 BC to the monumental statuary and architecture of the Kingdom of Kush, its last phase—the Meroitic period—ending around 350 CE (with its conquest by Ethiopia's Aksum). Beyond pottery items, the Kerma culture also made furniture that contained sculptures, such as gold cattle hoofs as the legs of beds. Sculpture during the Kingdom of Kush included full-sized statues (especially of kings and queens), smaller figurines (most commonly depicting royal servants), and reliefs in stone, which were influenced by the


title: Sculpture content: contemporary ancient Egyptian sculptural tradition. Sculpture in what is now Latin America developed in two separate and distinct areas, Mesoamerica in the north and Peru in the south. In both areas, sculpture was initially of stone, and later of terracotta and metal as the civilizations in these areas became more technologically proficient. The Mesoamerican region produced more monumental sculpture, from the massive block-like works of the Olmec and Toltec cultures, to the superb low reliefs that characterize the Mayan and Aztec cultures. In the Andean region, sculptures were typically small, but often show superb skill. In North America, wood was


title: Sculpture content: sculpted for totem poles, masks, utensils, War canoes and a variety of other uses, with distinct variation between different cultures and regions. The most developed styles are those of the Pacific Northwest Coast, where a group of elaborate and highly stylized formal styles developed forming the basis of a tradition that continues today. In addition to the famous totem poles, painted and carved house fronts were complemented by carved posts inside and out, as well as mortuary figures and other items. Among the Inuit of the far north, traditional carving styles in ivory and soapstone are still continued. The arrival


title: Sculpture content: of European Catholic culture readily adapted local skills to the prevailing Baroque style, producing enormously elaborate retablos and other mostly church sculptures in a variety of hybrid styles. The most famous of such examples in Canada is the altar area of the Notre Dame Basilica in Montreal, Quebec, which was carved by peasant "habitant" labourers. Later, artists trained in the Western academic tradition followed European styles until in the late 19th century they began to draw again on indigenous influences, notably in the Mexican baroque grotesque style known as Churrigueresque. Aboriginal peoples also adapted church sculpture in variations on Carpenter


title: Sculpture content: Gothic; one famous example is the "Church of the Holy Cross" in Skookumchuck Hot Springs, British Columbia. The history of sculpture in the United States after Europeans' arrival reflects the country's 18th-century foundation in Roman republican civic values and Protestant Christianity. Compared to areas colonized by the Spanish, sculpture got off to an extremely slow start in the British colonies, with next to no place in churches, and was only given impetus by the need to assert nationality after independence. American sculpture of the mid- to late-19th century was often classical, often romantic, but showed a bent for a dramatic,


title: Sculpture content: narrative, almost journalistic realism. Public buildings during the last quarter of the 19th century and the first half of the 20th century often provided an architectural setting for sculpture, especially in relief. By the 1930s the International Style of architecture and design and art deco characterized by the work of Paul Manship and Lee Lawrie and others became popular. By the 1950s, traditional sculpture education would almost be completely replaced by a Bauhaus-influenced concern for abstract design. Minimalist sculpture replaced the figure in public settings and architects almost completely stopped using sculpture in or on their designs. Modern sculptors (21st


title: Sculpture content: century) use both classical and abstract inspired designs. Beginning in the 1980s, there was a swing back toward figurative public sculpture; by 2000, many of the new public pieces in the United States were figurative in design. Modern classicism contrasted in many ways with the classical sculpture of the 19th century which was characterized by commitments to naturalism (Antoine-Louis Barye)—the melodramatic (François Rude) sentimentality (Jean-Baptiste Carpeaux)—or a kind of stately grandiosity (Lord Leighton). Several different directions in the classical tradition were taken as the century turned, but the study of the live model and the post-Renaissance tradition was still fundamental


title: Sculpture content: to them. Auguste Rodin was the most renowned European sculptor of the early 20th century. He is often considered a sculptural Impressionist, as are his students including Camille Claudel, and Hugo Rheinhold, attempting to model of a fleeting moment of ordinary life. Modern classicism showed a lesser interest in naturalism and a greater interest in formal stylization. Greater attention was paid to the rhythms of volumes and spaces—as well as greater attention to the contrasting qualities of surface (open, closed, planar, broken etc.) while less attention was paid to story-telling and convincing details of anatomy or costume. Greater attention was


title: Sculpture content: given to psychological effect than to physical realism, and influences from earlier styles worldwide were used. Early masters of modern classicism included: Aristide Maillol, Alexander Matveyev, Joseph Bernard, Antoine Bourdelle, Georg Kolbe, Libero Andreotti, Gustav Vigeland, Jan Stursa, Constantin Brâncuși. As the century progressed, modern classicism was adopted as the national style of the two great European totalitarian empires: Nazi Germany and Soviet Russia, who co-opted the work of earlier artists such as Kolbe and Wilhelm Lehmbruck in Germany and Matveyev in Russia. Over the 70 years of the USSR, new generations of sculptors were trained and chosen within their


title: Sculpture content: system, and a distinct style, socialist realism, developed, that returned to the 19th century's emphasis on melodrama and naturalism. Classical training was rooted out of art education in Western Europe (and the Americas) by 1970 and the classical variants of the 20th century were marginalized in the history of modernism. But classicism continued as the foundation of art education in the Soviet academies until 1990, providing a foundation for expressive figurative art throughout eastern Europe and parts of the Middle East. By the year 2000, the European classical tradition retains a wide appeal to the public but awaits an educational


title: Sculpture content: tradition to revive its contemporary development. Some of the modern classical became either more decorative/art deco (Paul Manship, Jose de Creeft, Carl Milles) or more abstractly stylized or more expressive (and Gothic) (Anton Hanak, Wilhelm Lehmbruck, Ernst Barlach, Arturo Martini)—or turned more to the Renaissance (Giacomo Manzù, Venanzo Crocetti) or stayed the same (Charles Despiau, Marcel Gimond). Modernist sculpture movements include Cubism, Geometric abstraction, De Stijl, Suprematism, Constructivism, Dadaism, Surrealism, Futurism, Formalism Abstract expressionism, Pop-Art, Minimalism, Land art, and Installation art among others. In the early days of the 20th century, Pablo Picasso revolutionized the art of sculpture when he


title: Sculpture content: began creating his "constructions" fashioned by combining disparate objects and materials into one constructed piece of sculpture; the sculptural equivalent of the collage in two-dimensional art. The advent of Surrealism led to things occasionally being described as "sculpture" that would not have been so previously, such as "involuntary sculpture" in several senses, including coulage. In later years Picasso became a prolific potter, leading, with interest in historic pottery from around the world, to a revival of ceramic art, with figures such as George E. Ohr and subsequently Peter Voulkos, Kenneth Price, and Robert Arneson. Marcel Duchamp originated the use of


title: Sculpture content: the "found object" (French: objet trouvé) or "readymade" with pieces such as "Fountain" (1917). Similarly, the work of Constantin Brâncuși at the beginning of the century paved the way for later abstract sculpture. In revolt against the naturalism of Rodin and his late-19th-century contemporaries, Brâncuși distilled subjects down to their essences as illustrated by the elegantly refined forms of his "Bird in Space" series (1924). Brâncuși's impact, with his vocabulary of reduction and abstraction, is seen throughout the 1930s and 1940s, and exemplified by artists such as Gaston Lachaise, Sir Jacob Epstein, Henry Moore, Alberto Giacometti, Joan Miró, Julio González,


title: Sculpture content: Pablo Serrano, Jacques Lipchitz and by the 1940s abstract sculpture was impacted and expanded by Alexander Calder, Len Lye, Jean Tinguely, and Frederick Kiesler who were pioneers of Kinetic art. Modernist sculptors largely missed out on the huge boom in public art resulting from the demand for war memorials for the two World Wars, but from the 1950s the public and commissioning bodies became more comfortable with Modernist sculpture and large public commissions both abstract and figurative became common. Picasso was commissioned to make a maquette for a huge -high public sculpture, the so-called "Chicago Picasso" (1967). His design was


title: Sculpture content: ambiguous and somewhat controversial, and what the figure represents is not clear; it could be a bird, a horse, a woman or a totally abstract shape. During the late 1950s and the 1960s abstract sculptors began experimenting with a wide array of new materials and different approaches to creating their work. Surrealist imagery, anthropomorphic abstraction, new materials and combinations of new energy sources and varied surfaces and objects became characteristic of much new modernist sculpture. Collaborative projects with landscape designers, architects, and landscape architects expanded the outdoor site and contextual integration. Artists such as Isamu Noguchi, David Smith, Alexander Calder,


title: Sculpture content: Jean Tinguely, Richard Lippold, George Rickey, Louise Bourgeois, and Louise Nevelson came to characterize the look of modern sculpture. By the 1960s Abstract expressionism, Geometric abstraction and Minimalism, which reduces sculpture to its most essential and fundamental features, predominated. Some works of the period are: the Cubi works of David Smith, and the welded steel works of Sir Anthony Caro, as well as welded sculpture by a large variety of sculptors, the large-scale work of John Chamberlain, and environmental installation scale works by Mark di Suvero. Other Minimalists include Tony Smith, Donald Judd, Robert Morris, Anne Truitt, Giacomo Benevelli, Arnaldo


title: Sculpture content: Pomodoro, Richard Serra, Dan Flavin, Carl Andre, and John Safer who added motion and monumentality to the theme of purity of line. During the 1960s and 1970s figurative sculpture by modernist artists in stylized forms was made by artists such as Leonard Baskin, Ernest Trova, George Segal, Marisol Escobar, Paul Thek, Robert Graham in a classic articulated style, and Fernando Botero bringing his painting's 'oversized figures' into monumental sculptures. Site specific and environmental art works are represented by artists: Andy Goldsworthy, Walter De Maria, Richard Long, Richard Serra, Robert Irwin, George Rickey and Christo and Jeanne-Claude led contemporary abstract sculpture


title: Sculpture content: in new directions. Artists created environmental sculpture on expansive sites in the 'land art in the American West' group of projects. These land art or 'earth art' environmental scale sculpture works exemplified by artists such as Robert Smithson, Michael Heizer, James Turrell (Roden Crater). Eva Hesse, Sol LeWitt, Jackie Winsor, Keith Sonnier, Bruce Nauman and Dennis Oppenheim among others were pioneers of Postminimalist sculpture. Also during the 1960s and 1970s artists as diverse as Eduardo Paolozzi, Chryssa, Claes Oldenburg, George Segal, Edward Kienholz, Nam June Paik, Wolf Vostell, Duane Hanson, and John DeAndrea explored abstraction, imagery and figuration through video


title: Sculpture content: art, environment, light sculpture, and installation art in new ways. Conceptual art is art in which the concept(s) or idea(s) involved in the work take precedence over traditional aesthetic and material concerns. Works include "One and Three Chairs", 1965, is by Joseph Kosuth, and "An Oak Tree" by Michael Craig-Martin, and those of Joseph Beuys, James Turrell and Jacek Tylicki. Some modern sculpture forms are now practiced outdoors, as environmental art and environmental sculpture, often in full view of spectators. Light sculpture, street art sculpture and site-specific art also often make use of the environment. Ice sculpture is a form


title: Sculpture content: of ephemeral sculpture that uses ice as the raw material. It is popular in China, Japan, Canada, Sweden, and Russia. Ice sculptures feature decoratively in some cuisines, especially in Asia. Kinetic sculptures are sculptures that are designed to move, which include mobiles. Snow sculptures are usually carved out of a single block of snow about on each side and weighing about 20–30 tons. The snow is densely packed into a form after having been produced by artificial means or collected from the ground after a snowfall. Sound sculptures take the form of indoor sound installations, outdoor installations such as aeolian


title: Sculpture content: harps, automatons, or be more or less near conventional musical instruments. Sound sculpture is often site-specific. Art toys have become another format for contemporary artists since the late 1990s, such as those produced by Takashi Murakami and Kid Robot, designed by Michael Lau, or hand-made by Michael Leavitt (artist). Sculptures are sensitive to environmental conditions such as temperature, humidity and exposure to light and ultraviolet light. Acid rain can also cause damage to certain building materials and historical monuments. This results when sulfuric acid in the rain chemically reacts with the calcium compounds in the stones (limestone, sandstone, marble and


title: Sculpture content: granite) to create gypsum, which then flakes off. At any time many contemporary sculptures have usually been on display in public places; theft was not a problem as pieces were instantly recognisable. In the early 21st century the value of metal rose to such an extent that theft of massive bronze sculpture for the value of the metal became a problem; sculpture worth millions being stolen and melted down for the relatively low value of the metal, a tiny fraction of the value of the artwork. Sculpture Sculpture is the branch of the visual arts that operates in three dimensions.


title: "Slime mold" content: is, simple brains." Atsushi Tero of Hokkaido University grew "Physarum" in a flat wet dish, placing the mold in a central position representing Tokyo and oat flakes surrounding it corresponding to the locations of other major cities in the Greater Tokyo Area. As "Physarum" avoids bright light, light was used to simulate mountains, water and other obstacles in the dish. The mold first densely filled the space with plasmodia, and then thinned the network to focus on efficiently connected branches. The network strikingly resembled Tokyo's rail system. Slime mold Slime mold or slime mould is an informal name given to


title: Switzerland content: of the Aare and Reuss rivers, near the town of Windisch, an outskirt of Brugg. The first and second century AD was an age of prosperity for the population living on the Swiss plateau. Several towns, like Aventicum, Iulia Equestris and Augusta Raurica, reached a remarkable size, while hundreds of agricultural estates (Villae rusticae) were founded in the countryside. Around 260 AD, the fall of the Agri Decumates territory north of the Rhine transformed today's Switzerland into a frontier land of the Empire. Repeated raids by the Alamanni tribes provoked the ruin of the Roman towns and economy, forcing the


title: Sun content: Sun The Sun is the star at the center of the Solar System. It is a nearly perfect sphere of hot plasma, with internal convective motion that generates a magnetic field via a dynamo process.<ref name="doi10.1146/annurev-astro-081913-040012"></ref> It is by far the most important source of energy for life on Earth. Its diameter is about 1.39 million kilometers, or 109 times that of Earth, and its mass is about 330,000 times that of Earth. It accounts for about 99.86% of the total mass of the Solar System. Roughly three quarters of the Sun's mass consists of hydrogen (~73%); the rest is


title: Sun content: mostly helium (~25%), with much smaller quantities of heavier elements, including oxygen, carbon, neon, and iron. The Sun is a G-type main-sequence star (G2V) based on its spectral class. As such, it is informally and not completely accurately referred to as a yellow dwarf (its light is closer to white than yellow). It formed approximately 4.6 billion years ago from the gravitational collapse of matter within a region of a large molecular cloud. Most of this matter gathered in the center, whereas the rest flattened into an orbiting disk that became the Solar System. The central mass became so hot


title: Sun content: and dense that it eventually initiated nuclear fusion in its core. It is thought that almost all stars form by this process. The Sun is roughly middle-aged; it has not changed dramatically for more than four billion years, and will remain fairly stable for more than another five billion years. It currently fuses about 600 million tons of hydrogen into helium every second, converting 4 million tons of matter into energy every second as a result. This energy, which can take between 10,000 and 170,000 years to escape from its core, is the source of the Sun's light and heat.


title: Sun content: In about 5 billion years, when hydrogen fusion in its core has diminished to the point at which the Sun is no longer in hydrostatic equilibrium, its core will undergo a marked increase in density and temperature while its outer layers expand to eventually become a red giant. It is calculated that the Sun will become sufficiently large to engulf the current orbits of Mercury and Venus, and render Earth uninhabitable. After this, it will shed its outer layers and become a dense type of cooling star known as a white dwarf, and no longer produce energy by fusion, but


title: Sun content: still glow and give off heat from its previous fusion. The enormous effect of the Sun on Earth has been recognized since prehistoric times, and the Sun has been regarded by some cultures as a deity. The synodic rotation of Earth and its orbit around the Sun are the basis of solar calendars, one of which is the predominant calendar in use today. The English proper name "Sun" developed from Old English "sunne" and may be related to "south". Cognates to English "sun" appear in other Germanic languages, including Old Frisian "sunne", "sonne", Old Saxon "sunna", Middle Dutch "sonne", modern


title: Sun content: Dutch "zon", Old High German "sunna", modern German "Sonne", Old Norse "sunna", and Gothic "sunnō". All Germanic terms for the Sun stem from Proto-Germanic *"sunnōn". The Latin name for the Sun, "Sol", is used at times as another name for the Sun, but is not commonly used in everyday English. "Sol" is also used by planetary astronomers to refer to the duration of a solar day on another planet, such as Mars. The related word "solar" is the usual adjectival term used for the Sun, in terms such as solar day, solar eclipse, and Solar System. A mean Earth solar


title: Sun content: day is approximately 24 hours, whereas a mean Martian 'sol' is 24 hours, 39 minutes, and 35.244 seconds. The English weekday name "Sunday" stems from Old English ("Sunnandæg"; "Sun's day", from before 700) and is ultimately a result of a Germanic interpretation of Latin "dies solis", itself a translation of the Greek ἡμέρα ἡλίου ("hēméra hēlíou"). Solar deities play a major role in many world religions and mythologies. The ancient Sumerians believed that the sun was Utu, the god of justice and twin brother of Inanna, the Queen of Heaven, who was identified as the planet Venus. Later, Utu was


title: Sun content: identified with the East Semitic god Shamash. Utu was regarded as a helper-deity, who aided those in distress, and, in iconography, he is usually portrayed with a long beard and clutching a saw, which represented his role as the dispenser of justice. From at least the 4th Dynasty of Ancient Egypt, the Sun was worshipped as the god Ra, portrayed as a falcon-headed divinity surmounted by the solar disk, and surrounded by a serpent. In the New Empire period, the Sun became identified with the dung beetle, whose spherical ball of dung was identified with the Sun. In the form


title: Sun content: of the Sun disc Aten, the Sun had a brief resurgence during the Amarna Period when it again became the preeminent, if not only, divinity for the Pharaoh Akhenaton. In Proto-Indo-European religion, the Sun was personified as the goddess "*Sehul". Derivatives of this goddess in Indo-European languages include the Old Norse "Sól", Sanskrit "Surya", Gaulish "Sulis", Lithuanian "Saulė", and Slavic "Solntse". In ancient Greek religion, the sun deity was the male god Helios, but traces of an earlier female solar deity are preserved in Helen of Troy. In later times, Helios was syncretized with Apollo. In the Bible, mentions the


title: Sun content: "Sun of Righteousness" (sometimes translated as the "Sun of Justice"), which some Christians have interpreted as a reference to the Messiah (Christ). In ancient Roman culture, Sunday was the day of the Sun god. It was adopted as the Sabbath day by Christians who did not have a Jewish background. The symbol of light was a pagan device adopted by Christians, and perhaps the most important one that did not come from Jewish traditions. In paganism, the Sun was a source of life, giving warmth and illumination to mankind. It was the center of a popular cult among Romans, who


title: Sun content: would stand at dawn to catch the first rays of sunshine as they prayed. The celebration of the winter solstice (which influenced Christmas) was part of the Roman cult of the unconquered Sun (Sol Invictus). Christian churches were built with an orientation so that the congregation faced toward the sunrise in the East. Tonatiuh, the Aztec god of the Sun, was usually depicted holding arrows and a shield and was closely associated with the practice of human sacrifice. The sun goddess Amaterasu is the most important deity in the Shinto religion, and she is believed to be the direct ancestor


title: Sun content: of all Japanese emperors. The Sun is a G-type main-sequence star that comprises about 99.86% of the mass of the Solar System. The Sun has an absolute magnitude of +4.83, estimated to be brighter than about 85% of the stars in the Milky Way, most of which are red dwarfs. The Sun is a Population I, or heavy-element-rich, star. The formation of the Sun may have been triggered by shockwaves from one or more nearby supernovae. This is suggested by a high abundance of heavy elements in the Solar System, such as gold and uranium, relative to the abundances of


title: Sun content: these elements in so-called Population II, heavy-element-poor, stars. The heavy elements could most plausibly have been produced by endothermic nuclear reactions during a supernova, or by transmutation through neutron absorption within a massive second-generation star. The Sun is by far the brightest object in the Earth's sky, with an apparent magnitude of −26.74. This is about 13 billion times brighter than the next brightest star, Sirius, which has an apparent magnitude of −1.46. The mean distance of the Sun's center to Earth's center is approximately , though the distance varies as Earth moves from perihelion in January to aphelion in


title: Sun content: July. At this average distance, light travels from the Sun's horizon to Earth's horizon in about 8 minutes and 19 seconds, while light from the closest points of the Sun and Earth takes about two seconds less. The energy of this sunlight supports almost all life on Earth by photosynthesis, and drives Earth's climate and weather. The Sun does not have a definite boundary, but its density decreases exponentially with increasing height above the photosphere. For the purpose of measurement, however, the Sun's radius is considered to be the distance from its center to the edge of the photosphere, the


title: Sun content: apparent visible surface of the Sun. By this measure, the Sun is a near-perfect sphere with an oblateness estimated at about 9 millionths, which means that its polar diameter differs from its equatorial diameter by only . The tidal effect of the planets is weak and does not significantly affect the shape of the Sun. The Sun rotates faster at its equator than at its poles. This differential rotation is caused by convective motion due to heat transport and the Coriolis force due to the Sun's rotation. In a frame of reference defined by the stars, the rotational period is


title: Sun content: approximately 25.6 days at the equator and 33.5 days at the poles. Viewed from Earth as it orbits the Sun, the "apparent rotational period" of the Sun at its equator is about 28 days. The solar constant is the amount of power that the Sun deposits per unit area that is directly exposed to sunlight. The solar constant is equal to approximately (watts per square meter) at a distance of one astronomical unit (AU) from the Sun (that is, on or near Earth). Sunlight on the surface of Earth is attenuated by Earth's atmosphere, so that less power arrives at


title: Sun content: the surface (closer to ) in clear conditions when the Sun is near the zenith. Sunlight at the top of Earth's atmosphere is composed (by total energy) of about 50% infrared light, 40% visible light, and 10% ultraviolet light. The atmosphere in particular filters out over 70% of solar ultraviolet, especially at the shorter wavelengths. Solar ultraviolet radiation ionizes Earth's dayside upper atmosphere, creating the electrically conducting ionosphere. The Sun's color is white, with a CIE color-space index near (0.3, 0.3), when viewed from space or when the Sun is high in the sky. When measuring all the photons emitted,


title: Sun content: the Sun is actually emitting more photons in the green portion of the spectrum than any other. When the Sun is low in the sky, atmospheric scattering renders the Sun yellow, red, orange, or magenta. Despite its typical whiteness, most people mentally picture the Sun as yellow; the reasons for this are the subject of debate. The Sun is a G2V star, with "G2" indicating its surface temperature of approximately 5,778 K (5,505 °C, 9,941 °F), and "V" that it, like most stars, is a main-sequence star. The average luminance of the Sun is about 1.88 giga candela per square


title: Sun content: metre, but as viewed through Earth's atmosphere, this is lowered to about 1.44 Gcd/m. However, the luminance is not constant across the disk of the Sun (limb darkening). The Sun is composed primarily of the chemical elements hydrogen and helium. At this time in the Sun's life, they account for 74.9% and 23.8% of the mass of the Sun in the photosphere, respectively. All heavier elements, called "metals" in astronomy, account for less than 2% of the mass, with oxygen (roughly 1% of the Sun's mass), carbon (0.3%), neon (0.2%), and iron (0.2%) being the most abundant. The Sun's original


title: Sun content: chemical composition was inherited from the interstellar medium out of which it formed. Originally it would have contained about 71.1% hydrogen, 27.4% helium, and 1.5% heavier elements. The hydrogen and most of the helium in the Sun would have been produced by Big Bang nucleosynthesis in the first 20 minutes of the universe, and the heavier elements were produced by previous generations of stars before the Sun was formed, and spread into the interstellar medium during the final stages of stellar life and by events such as supernovae. Since the Sun formed, the main fusion process has involved fusing hydrogen


title: Sun content: into helium. Over the past 4.6 billion years, the amount of helium and its location within the Sun has gradually changed. Within the core, the proportion of helium has increased from about 24% to about 60% due to fusion, and some of the helium and heavy elements have settled from the photosphere towards the center of the Sun because of gravity. The proportions of metals (heavier elements) is unchanged. Heat is transferred outward from the Sun's core by radiation rather than by convection (see Radiative zone below), so the fusion products are not lifted outward by heat; they remain in


title: Sun content: the core and gradually an inner core of helium has begun to form that cannot be fused because presently the Sun's core is not hot or dense enough to fuse helium. In the current photosphere the helium fraction is reduced, and the metallicity is only 84% of what it was in the protostellar phase (before nuclear fusion in the core started). In the future, helium will continue to accumulate in the core, and in about 5 billion years this gradual build-up will eventually cause the Sun to exit the main sequence and become a red giant. The chemical composition of


title: Sun content: the photosphere is normally considered representative of the composition of the primordial Solar System. The solar heavy-element abundances described above are typically measured both using spectroscopy of the Sun's photosphere and by measuring abundances in meteorites that have never been heated to melting temperatures. These meteorites are thought to retain the composition of the protostellar Sun and are thus not affected by settling of heavy elements. The two methods generally agree well. In the 1970s, much research focused on the abundances of iron-group elements in the Sun. Although significant research was done, until 1978 it was difficult to determine the


title: Sun content: abundances of some iron-group elements (e.g. cobalt and manganese) via spectrography because of their hyperfine structures. The first largely complete set of oscillator strengths of singly ionized iron-group elements were made available in the 1960s, and these were subsequently improved. In 1978, the abundances of singly ionized elements of the iron group were derived. Various authors have considered the existence of a gradient in the isotopic compositions of solar and planetary noble gases, e.g. correlations between isotopic compositions of neon and xenon in the Sun and on the planets. Prior to 1983, it was thought that the whole Sun has


title: Sun content: the same composition as the solar atmosphere. In 1983, it was claimed that it was fractionation in the Sun itself that caused the isotopic-composition relationship between the planetary and solar-wind-implanted noble gases. The structure of the Sun contains the following layers: The core of the Sun extends from the center to about 20–25% of the solar radius. It has a density of up to (about 150 times the density of water) and a temperature of close to 15.7 million kelvins (K). By contrast, the Sun's surface temperature is approximately 5,800 K. Recent analysis of SOHO mission data favors a faster


title: Sun content: rotation rate in the core than in the radiative zone above. Through most of the Sun's life, energy has been produced by nuclear fusion in the core region through a series of steps called the p–p (proton–proton) chain; this process converts hydrogen into helium. Only 0.8% of the energy generated in the Sun comes from the CNO cycle, though this proportion is expected to increase as the Sun becomes older. The core is the only region in the Sun that produces an appreciable amount of thermal energy through fusion; 99% of the power is generated within 24% of the Sun's


title: Sun content: radius, and by 30% of the radius, fusion has stopped nearly entirely. The remainder of the Sun is heated by this energy as it is transferred outwards through many successive layers, finally to the solar photosphere where it escapes into space as sunlight or the kinetic energy of particles. The proton–proton chain occurs around times each second in the core, converting about 3.7 protons into alpha particles (helium nuclei) every second (out of a total of ~8.9 free protons in the Sun), or about 6.2 kg/s. Fusing four free protons (hydrogen nuclei) into a single alpha particle (helium nucleus) releases


title: Sun content: around 0.7% of the fused mass as energy, so the Sun releases energy at the mass–energy conversion rate of 4.26 million metric tons per second (which requires 600 metric megatons of hydrogen ), for 384.6 yottawatts (), or 9.192 megatons of TNT per second. However, the large power output of the Sun is mainly due to the huge size and density of its core (compared to Earth and objects on Earth), with only a fairly small amount of power being generated per cubic metre. Theoretical models of the Sun's interior indicate a power density, or energy production, of approximately 276.5


title: Sun content: watts per cubic metre, which is about the same rate of power production as takes place in reptile metabolism or a compost pile. The fusion rate in the core is in a self-correcting equilibrium: a slightly higher rate of fusion would cause the core to heat up more and expand slightly against the weight of the outer layers, reducing the density and hence the fusion rate and correcting the perturbation; and a slightly lower rate would cause the core to cool and shrink slightly, increasing the density and increasing the fusion rate and again reverting it to its present rate.


title: Sun content: From the core out to about 0.7 solar radii, thermal radiation is the primary means of energy transfer. The temperature drops from approximately 7 million to 2 million kelvins with increasing distance from the core. This temperature gradient is less than the value of the adiabatic lapse rate and hence cannot drive convection, which explains why the transfer of energy through this zone is by radiation instead of thermal convection. Ions of hydrogen and helium emit photons, which travel only a brief distance before being reabsorbed by other ions. The density drops a hundredfold (from 20 g/cm to 0.2 g/cm)


title: Sun content: from 0.25 solar radii to the 0.7 radii, the top of the radiative zone. The radiative zone and the convective zone are separated by a transition layer, the tachocline. This is a region where the sharp regime change between the uniform rotation of the radiative zone and the differential rotation of the convection zone results in a large shear between the two—a condition where successive horizontal layers slide past one another. Presently, it is hypothesized (see Solar dynamo) that a magnetic dynamo within this layer generates the Sun's magnetic field. The Sun's convection zone extends from 0.7 solar radii (500,000


title: Sun content: km) to near the surface. In this layer, the solar plasma is not dense enough or hot enough to transfer the heat energy of the interior outward via radiation. Instead, the density of the plasma is low enough to allow convective currents to develop and move the Sun's energy outward towards its surface. Material heated at the tachocline picks up heat and expands, thereby reducing its density and allowing it to rise. As a result, an orderly motion of the mass develops into thermal cells that carry the majority of the heat outward to the Sun's photosphere above. Once the


title: Sun content: material diffusively and radiatively cools just beneath the photospheric surface, its density increases, and it sinks to the base of the convection zone, where it again picks up heat from the top of the radiative zone and the convective cycle continues. At the photosphere, the temperature has dropped to 5,700 K and the density to only 0.2 g/m (about 1/6,000 the density of air at sea level). The thermal columns of the convection zone form an imprint on the surface of the Sun giving it a granular appearance called the solar granulation at the smallest scale and supergranulation at larger


title: Sun content: scales. Turbulent convection in this outer part of the solar interior sustains "small-scale" dynamo action over the near-surface volume of the Sun. The Sun's thermal columns are Bénard cells and take the shape of hexagonal prisms. The visible surface of the Sun, the photosphere, is the layer below which the Sun becomes opaque to visible light. Above the photosphere visible sunlight is free to propagate into space, and almost all of its energy escapes the Sun entirely. The change in opacity is due to the decreasing amount of H ions, which absorb visible light easily. Conversely, the visible light we


title: Sun content: see is produced as electrons react with hydrogen atoms to produce H ions. The photosphere is tens to hundreds of kilometers thick, and is slightly less opaque than air on Earth. Because the upper part of the photosphere is cooler than the lower part, an image of the Sun appears brighter in the center than on the edge or "limb" of the solar disk, in a phenomenon known as limb darkening. The spectrum of sunlight has approximately the spectrum of a black-body radiating at 5,777 K, interspersed with atomic absorption lines from the tenuous layers above the photosphere. The photosphere


title: Sun content: has a particle density of ~10 m (about 0.37% of the particle number per volume of Earth's atmosphere at sea level). The photosphere is not fully ionized—the extent of ionization is about 3%, leaving almost all of the hydrogen in atomic form. During early studies of the optical spectrum of the photosphere, some absorption lines were found that did not correspond to any chemical elements then known on Earth. In 1868, Norman Lockyer hypothesized that these absorption lines were caused by a new element that he dubbed "helium", after the Greek Sun god Helios. Twenty-five years later, helium was isolated


title: Sun content: on Earth. During a total solar eclipse, when the disk of the Sun is covered by that of the Moon, parts of the Sun's surrounding atmosphere can be seen. It is composed of four distinct parts: the chromosphere, the transition region, the corona and the heliosphere. The coolest layer of the Sun is a temperature minimum region extending to about above the photosphere, and has a temperature of about . This part of the Sun is cool enough to allow the existence of simple molecules such as carbon monoxide and water, which can be detected via their absorption spectra. The


title: Sun content: chromosphere, transition region, and corona are much hotter than the surface of the Sun. The reason is not well understood, but evidence suggests that Alfvén waves may have enough energy to heat the corona. Above the temperature minimum layer is a layer about thick, dominated by a spectrum of emission and absorption lines. It is called the "chromosphere" from the Greek root "chroma", meaning color, because the chromosphere is visible as a colored flash at the beginning and end of total solar eclipses. The temperature of the chromosphere increases gradually with altitude, ranging up to around near the top. In


title: Sun content: the upper part of the chromosphere helium becomes partially ionized. Above the chromosphere, in a thin (about 200 km) transition region, the temperature rises rapidly from around 20,000 K in the upper chromosphere to coronal temperatures closer to 1,000,000 K. The temperature increase is facilitated by the full ionization of helium in the transition region, which significantly reduces radiative cooling of the plasma. The transition region does not occur at a well-defined altitude. Rather, it forms a kind of nimbus around chromospheric features such as spicules and filaments, and is in constant, chaotic motion. The transition region is not easily


title: Sun content: visible from Earth's surface, but is readily observable from space by instruments sensitive to the extreme ultraviolet portion of the spectrum. The corona is the next layer of the Sun. The low corona, near the surface of the Sun, has a particle density around 10 m to 10 m. The average temperature of the corona and solar wind is about 1,000,000–2,000,000 K; however, in the hottest regions it is 8,000,000–20,000,000 K. Although no complete theory yet exists to account for the temperature of the corona, at least some of its heat is known to be from magnetic reconnection. The corona


title: Sun content: is the extended atmosphere of the Sun, which has a volume much larger than the volume enclosed by the Sun's photosphere. A flow of plasma outward from the Sun into interplanetary space is the solar wind. The heliosphere, the tenuous outermost atmosphere of the Sun, is filled with the solar wind plasma. This outermost layer of the Sun is defined to begin at the distance where the flow of the solar wind becomes "superalfvénic"—that is, where the flow becomes faster than the speed of Alfvén waves, at approximately 20 solar radii (0.1 AU). Turbulence and dynamic forces in the heliosphere


title: Sun content: cannot affect the shape of the solar corona within, because the information can only travel at the speed of Alfvén waves. The solar wind travels outward continuously through the heliosphere, forming the solar magnetic field into a spiral shape, until it impacts the heliopause more than 50 AU from the Sun. In December 2004, the Voyager 1 probe passed through a shock front that is thought to be part of the heliopause. In late 2012 Voyager 1 recorded a marked increase in cosmic ray collisions and a sharp drop in lower energy particles from the solar wind, which suggested that


title: Sun content: the probe had passed through the heliopause and entered the interstellar medium. High-energy gamma-ray photons initially released with fusion reactions in the core are almost immediately absorbed by the solar plasma of the radiative zone, usually after traveling only a few millimeters. Re-emission happens in a random direction and usually at a slightly lower energy. With this sequence of emissions and absorptions, it takes a long time for radiation to reach the Sun's surface. Estimates of the photon travel time range between 10,000 and 170,000 years. In contrast, it takes only 2.3 seconds for the neutrinos, which account for about


title: Sun content: 2% of the total energy production of the Sun, to reach the surface. Because energy transport in the Sun is a process that involves photons in thermodynamic equilibrium with matter, the time scale of energy transport in the Sun is longer, on the order of 30,000,000 years. This is the time it would take the Sun to return to a stable state, if the rate of energy generation in its core were suddenly changed. Neutrinos are also released by the fusion reactions in the core, but, unlike photons, they rarely interact with matter, so almost all are able to escape


title: Sun content: the Sun immediately. For many years measurements of the number of neutrinos produced in the Sun were lower than theories predicted by a factor of 3. This discrepancy was resolved in 2001 through the discovery of the effects of neutrino oscillation: the Sun emits the number of neutrinos predicted by the theory, but neutrino detectors were missing of them because the neutrinos had changed flavor by the time they were detected. The Sun has a magnetic field that varies across the surface of the Sun. Its polar field is , whereas the field is typically in features on the Sun


title: Sun content: called sunspots and in solar prominences. The magnetic field also varies in time and location. The quasi-periodic 11-year solar cycle is the most prominent variation in which the number and size of sunspots waxes and wanes. Sunspots are visible as dark patches on the Sun's photosphere, and correspond to concentrations of magnetic field where the convective transport of heat is inhibited from the solar interior to the surface. As a result, sunspots are slightly cooler than the surrounding photosphere, and, so, they appear dark. At a typical solar minimum, few sunspots are visible, and occasionally none can be seen at


title: Sun content: all. Those that do appear are at high solar latitudes. As the solar cycle progresses towards its maximum, sunspots tend form closer to the solar equator, a phenomenon known as Spörer's law. The largest sunspots can be tens of thousands of kilometers across. An 11-year sunspot cycle is half of a 22-year Babcock–Leighton dynamo cycle, which corresponds to an oscillatory exchange of energy between toroidal and poloidal solar magnetic fields. At solar-cycle maximum, the external poloidal dipolar magnetic field is near its dynamo-cycle minimum strength, but an internal toroidal quadrupolar field, generated through differential rotation within the tachocline, is near


title: Sun content: its maximum strength. At this point in the dynamo cycle, buoyant upwelling within the convective zone forces emergence of toroidal magnetic field through the photosphere, giving rise to pairs of sunspots, roughly aligned east–west and having footprints with opposite magnetic polarities. The magnetic polarity of sunspot pairs alternates every solar cycle, a phenomenon known as the Hale cycle. During the solar cycle's declining phase, energy shifts from the internal toroidal magnetic field to the external poloidal field, and sunspots diminish in number and size. At solar-cycle minimum, the toroidal field is, correspondingly, at minimum strength, sunspots are relatively rare, and


title: Sun content: the poloidal field is at its maximum strength. With the rise of the next 11-year sunspot cycle, differential rotation shifts magnetic energy back from the poloidal to the toroidal field, but with a polarity that is opposite to the previous cycle. The process carries on continuously, and in an idealized, simplified scenario, each 11-year sunspot cycle corresponds to a change, then, in the overall polarity of the Sun's large-scale magnetic field. The solar magnetic field extends well beyond the Sun itself. The electrically conducting solar wind plasma carries the Sun's magnetic field into space, forming what is called the interplanetary


title: Sun content: magnetic field. In an approximation known as ideal magnetohydrodynamics, plasma particles only move along the magnetic field lines. As a result, the outward-flowing solar wind stretches the interplanetary magnetic field outward, forcing it into a roughly radial structure. For a simple dipolar solar magnetic field, with opposite hemispherical polarities on either side of the solar magnetic equator, a thin current sheet is formed in the solar wind. At great distances, the rotation of the Sun twists the dipolar magnetic field and corresponding current sheet into an Archimedean spiral structure called the Parker spiral. The interplanetary magnetic field is much stronger


title: Sun content: than the dipole component of the solar magnetic field. The Sun's dipole magnetic field of 50–400 μT (at the photosphere) reduces with the inverse-cube of the distance to about 0.1 nT at the distance of Earth. However, according to spacecraft observations the interplanetary field at Earth's location is around 5 nT, about a hundred times greater. The difference is due to magnetic fields generated by electrical currents in the plasma surrounding the Sun. The Sun's magnetic field leads to many effects that are collectively called solar activity. Solar flares and coronal-mass ejections tend to occur at sunspot groups. Slowly changing


title: Sun content: high-speed streams of solar wind are emitted from coronal holes at the photospheric surface. Both coronal-mass ejections and high-speed streams of solar wind carry plasma and interplanetary magnetic field outward into the Solar System. The effects of solar activity on Earth include auroras at moderate to high latitudes and the disruption of radio communications and electric power. Solar activity is thought to have played a large role in the formation and evolution of the Solar System. With solar-cycle modulation of sunspot number comes a corresponding modulation of space weather conditions, including those surrounding Earth where technological systems can be affected.