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German The German Classroom was designed by German-born architect Frank A. Linder to reflect the 16th century German Renaissance as exemplified in the Alte Aula (Great Hall) of the University of Heidelberg. The woodwork of the room was done by German-born Philadelphia decorator Gustav Ketterer and includes walnut paneling framing the blackboards, columns carved with arabesques flanking the two entrance doorways, and support broken-arch pediments surmounted by carved polychromed crests of the two oldest German universities: Heidelberg (1386) and Leipzig (1409). The doors are mounted with ornate wrought-iron hinges and locks, and their upper panels are decorated with intarsia depicting the central square of Nürnberg on the front door and the fountain of Rothenburg on the rear door.
Carved in the architrave above the paneling are the names of famous philosophers, poets, musicians, artists, and scientists. The intarsia doors of the four corner cabinets feature tales from German folklore including Parsifal who searched for the Holy Grail, Siegfried who was the hero of the Nibelungenlied, the maiden wooed in Goethe's poem Heidenröslein, and Lorelei who was the golden-haired Rhine maiden whose song lured sailors to destruction. Painted on the escutcheon above the front blackboard are words from Friedrich Schiller's Das Ideal und das Leben, "Stern endeavor, which no arduous task can shake, to the hidden fount of true attains."
The rear wall has a quotation from Johann Wolfgang von Goethe's Was wir bringen which reads: "Great mastery results from wise restraint, and law alone points the way to liberty." Furniture includes the professor's leather upholstered chair stands on a small platform behind a burled walnut table and student tablet armchairs are walnut with scroll backs. Wrought-iron chandeliers are the work of German craftsman. The display case contains gifts of artworks and books from Germany's Ministry of Education. The stained-glass windows were designed by master stained glass artist Charles Connick, however they were not completed until 1953 by Connick protege Frances Van Arsdale Skinner.
The windows depict characters in the Grimm Brothers' fairy tales such as Little Red Riding Hood, Snow White and the Seven Dwarfs, Hansel and Gretel, and Cinderella. Greek The classical architecture of the Greek Classroom represents 5th-century BCE. Athens, the Golden Age of Pericles and includes marble columns and a coffered ceiling. Colored details from the Acropolis' Propylaea and Erectheum appear on white marble. The floor is paved with rectangular slabs of Dionessos Pentelic marble with dark vein. Gray Kokinara marble is used for the dado. The room's columns and pilasters, as well as the coffered ceiling, bear painted decorations identical to those used on ancient Greek structures.
The artwork was done by Athenian artist Demetrios Kokotsis who used the traditional encaustic painting method, employing earth colors and beeswax applied freehand which was then overlaid with 24-carat gold leaf rubbed on by polishing bones which required two men more than seven months to complete. White oak furniture, patterned after designs on Greek vases, is decorated with gold-leaf carvings and sunburst inlays of ebony. Student chair backs carry the names of Greek islands and towns. The professor's and guests' chairs bear the names of Plato, Aristotle, and Socrates. A line from Homer's Iliad exhorts students to strive for nobility and excellence.
The deep red wall color is repeated in the drapery valance with its Greek key design. Archives in the alcove cabinet record visits by the Queen of Greece, and by ecclesiastic and diplomatic officials. In 1940, one of two marble pilasters for the room that was being constructed in Greece from the Mt Pentele stone quarry used to build the Parthenon, cracked shortly before shipping to the United States. With an invading World War II army massing on its borders, the column could not be replaced. Greek architect John Travlos ordered a matching crack etched into the undamaged column in order to preserve the symmetry.
The marble was transported on the last ship to sail to America prior to the invasion and occupation of Greece. In November 1941, Travlos crouched under a blanket in his apartment closet listening to banned BBC radio broadcasts. Suddenly, Greek ecclesiastical music spouted from the radio, and Travlos heard the people of Pittsburgh dedicate his memorial to Greece. Hungarian Dénes Györgyi, a professor at the Industrial Art School in Budapest, won the Hungarian Classroom design competition sponsored by Hungary's Ministry of Education in 1930 which features Magyar folk art combined with deep wood carvings and historic stained glass windows. The walls of the room are oak veneer stained a soft tobacco brown.
The wood in the panels was carefully selected and matched, so that the natural grains form interesting decorative patterns. The ceiling is 70 wooden cazettas suspended in a wooden frame and has a predominant hue of "paprika red", a color inspired by the peppers which are hung to dry over white fences in Hungary. The cazettas are decorated with folk motifs (birds, hearts, and tulips) in turquoise, green, and white were painted by Antal Diossy in Budapest. Joining the ceiling and walls is an inscription frieze with the first two stanzas of Himnusz, the Hungarian National Anthem by Ferenc Kölcsey.
Above the blackboard is the coat of arms of the University of Buda which was founded in 1388. At the top is the crown of St. Stephen, the patron saint of Hungary and its first Christian king. The student seats are made of oak and are unadorned except for stylized carved tulip ornaments on the back. A bench along the rear wall and guest chairs are upholstered in blue. Along the corridor wall, panels carved with floral, plant, and bird designs invoke a "tulip chest" which are the traditional hope chests of Hungarian village brides that are decorated with tulips.
In the display case lined with soft blue velvet is an exhibit of Hungarian porcelain, lace, embroidery, and costumed dolls. Stained and painted glass windows depict the legend of Hungary's founding as well as important events in the nation's history and culture. The rear window depicts King Nimrod and his sons, Hunor and Magor, who pursued a white stag from the east to the fertile Danube plain. Descendants of Hunor became the Huns and those of Magor became the Magyars. The bay windows commemorate historic figures and events of the Middle Ages, Renaissance, and 17th and 19th centuries. The oak entrance doors bears deep carvings of tulips, pomegranate leaves, daisies, and wheat.
The door's center panel states the date of the room's completion in 1938. The carvings were made by American wood carvers of Hungarian birth from plaster models that were made in Budapest to ensure Magyar authenticity. Indian The Indian Classroom is modeled on a typical 4th-9th century AD courtyard from Nalanda University, a Buddhist monastic university in Nalanda. At its peak, the university's five temples and 11 monasteries covered and attracted thousands of students from all over Asia. The room depicts a classroom courtyard at Nalanda. The pale rose bricks, specially fabricated to reflect the hue and texture of the original, form the walls, floor, pilasters, and niches.
Six stone columns decorated with rosettes, swags, and fruit echo those found at Nalanda. The rear sculpture wall, a scaled down version of one at Nalanda's Stupa #3, bears images of six Bodhisattvas. Flanking display cases hold replicas of ancient bronze sculptures found at the site. A watercolor triptych depicts male and female students at Nalanda as scholar-monk Silabhadra says farewell to 7th-century Chinese traveler Xuanzang. Gurus taught classes in the courtyards, which were surrounded by residential cells. The cherry wood chalkboard doors and flanking cabinets bear carved seals of Nalanda University with recumbent deer above a Sanskrit inscription. Cast steel grilles in front of the windows, hand wrought into forms which reflect decorative elements of the columns, filter the light and soften the view of the 20th-century outside world.
Renaissance 3 Architects received the Master Builders Association Craftsmanship Award for its construction. Irish The Irish Classroom is the smallest of the Nationality Rooms. The limestone room is designed in Irish Romanesque style, which flourished from the 6th to the 12th centuries and is similar in type, size, and materials to oratories first built on the west coast of Ireland. Adapted from Killeshin Chapel in County Carlow, the triangular doorway gable is carved with human and animal masks against a background of zig-zag and beaded designs. The blackboard frame's pendental arches are carved with foliage, images of wolfhounds, and stylized cat masks.
On the opposite wall a sculptured stone chest, under a monumental recessed arch, is patterned after a bishop's tomb in Cormac's chapel. Its ornate sculpture depicts the "Great Beast," a greyhound-like animal wreathed in interlaced ornaments. On the chest rests a replica of the Gospels from the Book of Kells. The wrought-iron case bears bird and beast designs drawn from the Book of Kells. Stained-glass windows, created in 1956/7 by the Harry Clarke Studios in Dublin, portray famous teachers at three of Ireland's oldest centers of learning; St. Finnian at Clonard, St. Columkille at Derry, and St. Carthach at Lismore.
Illuminations in the Book of Kells inspired the chair design, except for the wolfhound heads. The oak-beamed ceiling is characteristic of Irish oratories. The cornerstone, from the Abbey of Clonmacnoise, is carved with the Gaelic motto, "For the Glory of God and the Honour of Ireland." The cornerstone conceals a container of earth from Northern Ireland (County Armagh) and the Republic of Ireland (County Meath). The room was designed by Harold G. Leask, the prominent architect with The Office of Public Works (The O.P.W.) in Ireland. Gov. David L. Lawrence, Art Rooney Sr., founding owner of the Pittsburgh Steelers, and James W. Knox, a member of the Pittsburgh Irish community, were on the room's organizing committee.
After the assassination of President John F. Kennedy, Jacqueline Kennedy ordered a Marine guard to deliver the Oval Office Presidential and American flags to Evelyn Lincoln, private secretary to the president. In her will, Lincoln bequeathed the flags to the University of Pittsburgh for the Irish Room in honor of Knox. The John F. Kennedy scholarship for study in Ireland and a James W. Knox endowment for graduate study abroad were created from the proceeds generated from their auction. Israel Heritage The Israel Heritage Classroom reflects the simplicity of a 1st-century Galilean stone dwelling or house of assembly, this room's benches are patterned after those in the 2nd-3rd-century synagogue of Capernaum.
The Ten Commandments, carved in Hebrew, grace the oak entrance door. Grapes, pomegranates, and dates on the stone frieze, copied from Capernaum, represent crops grown in the Galilee. On the window wall, an inscription discovered in the 6th-century Rehob synagogue cites the Talmudic laws governing the growing of crops each seventh year. A scroll fragment in the rear case replicates the Dead Sea Isaiah Scroll segment which contains the prophecy "They shall beat their swords into plowshares and their spears into pruning hooks..." Ancient wine jars flank the scroll. The professor's table, based on one found in Jerusalem's 1st-century burnt house, stands before a copy of the only existing stone Menorah which served as a functional candelabrum.
The quotation on the chair reads: "I learned much from my teachers, more from my colleagues, and most of all from my pupils." Three segments from the 6th-century Dura Europos murals grace the chalkboard doors, Ezra the Scribe, reads the law; Moses brings forth water for the 12 tribes; and the sons of Aaron consecrate the Temple. Oak benches bear the names of the 12 tribes of Israel. The floor mosaic replicates one in the 6th century Galilean synagogue of Beth Alpha. Italian The Italian Classroom reflects the serenity of a 15th-century Tuscan monastery, with its traditional devotion to religion, art, music, and education.
The rear choir stall bench and shuttered windows introduce the monastic theme. The blackboard doors recall an armadio, a cabinet behind an altar used to hold priestly vestments. The turquoise soffitto a cassettoni (coffered ceiling), embellished with carved, gold-leafed rosettes, was inspired by one originally in the San Domenico Convent at Pesaro. In the architrave, names of famous Italians are inlaid in olive wood. The lettering resembles that used in the inscription on the Arch of Titus in Rome. Bay benches are cushioned in red velvet. The red tile floor is set in a herring-bone pattern similar to that of Florence's Palazzo Vecchio.
An original Florentine fireplace, made of sandstone from the quarries of Fiesole, bears the carved Latin inscription, "O Lord, do not forsake me." On either side stand Savonarola chairs. Monastery bench designs, adapted for student use, are carved with names and founding dates of Italian universities. The oldest is the University of Bologna, established in 1088. From the front of the room, a bronze bust of Dante Alighieri faces Giovanni Romagnoli's mural of Elena Lucrezia Cornaro Piscopia, the first woman in the world to achieve a university degree when she was awarded a Doctor of Philosophy degree in 1678 by the University of Padua.
Japanese The Japanese Nationality Room celebrates traditional Japanese carpentry and woodcraft, evoking the mid-18th century minka which were houses of the non-ruling classes of Japan. This room is representative of minka that might be the residence of an important village leader in a farm village on the outskirts of Kyoto and the design represents the core rooms of the house: a plank-floored ima or household sitting room and the adjacent doma, an area with a compacted earthen floor used as an entry-way, for cooking and as a work space. The doma was also a space for household life, where farm, business and craft activities could be carried out under a roof.
In the past it also provided a place for drying grain during rainy weather. A central feature of the room is the massive, rough-hewn beam, the ushibari of Japanese pine, supported by posts at the boundary of the ima and doma elements of the room. The main beam in this room had been carefully preserved by the carpenters in Japan for many years until a project could be found to appropriately utilize its unique curvature. To accommodate the weight concentrated on the primary post, the daikokubashira, the layout of the room has been designed so that this main post sits directly above the building's existing superstructure.
The major posts are made of zelkova, (keyaki), a hardwood with a distinctive grain pattern. The other beams are made of American pine. The posts and beams are connected without nails, using traditional joinery techniques. The ceiling is of bamboo with joined beams which would have allowed for the circulation of warm air from fireplaces below. The walls mimics the typical mud plaster walls through the use of textured wallpaper and wooden wainscoting for greater durability. The bay window is a structure not in keeping with traditional Japanese design and has been masked with panels that suggest shôji, sliding doors of lattice frames, covered with translucent paper.
The ima is suggested with a plank wood floor covering the largest portion of the room. The floor toward the front of the room is made of a simulated earthen material to represent a portion of the doma where it meets the ima's wooden floor. Although the traditional design would call for the wooden floor to be much higher than the dirt floor, this feature has been eliminated in the classroom for practicality. Located on the rear wall, is the tokonoma, a raised alcove for the display of treasured objects, flower arrangements, and seasonal decorations. The tokonoma has been built in shoin-style, with shôji along its exterior side.
The corner post, tokobashira, is made of ebony and the floor of the tokonoma is tatami. The display cases at the rear of the room and along the interior wall contain artifacts in keeping with the period and include a chagama and furo, an iron kettle with metal charcoal hearth/brazier combination, used in the "tea ceremony." While typical minka would have no chairs at all, in keeping with its function as a classroom, the classroom has wooden chairs designed and crafted specifically for students and are consistent in design with the rest of the room. Sliding wooden panels cover the blackboard at the front of the room.
The interior surface of the entry door has been modified with a wooden treatment that suggests the sliding door that was the typical entrance to a house of this period. Korean The Korean Nationality Room is based on the 14th century Myeong-nyundang (Hall of Enlightenment), the main building at the Sungkyunkwan in Seoul which served as Korea's royal academy during the Goryeo and Joseon dynasties from 918 to 1897. The room mimics the three connected rooms of the Myeong-nyundan with twin oak columns forming a symbolic boundary and a central room featuring a lofted ceiling that contains two hand-carved phoenixes facing a symbolic pearl of wisdom, a design inspired by the royal palace of the Joseon Dynasty.
The room was primarily built off-site in Korea, disassembled, and shipped to Pittsburgh where it was reassembled in the Cathedral of Learning by Korean carpenters who kept with traditional Korean building practices of not using nails or screws in construction. The room features hand cut and hand engraved Douglas fir and red pine logs from South Korea that include swirling engraved designs based on traditional Korean architecture. Windows are covered with a specially produced paper product made of mulberry tree fiber. A symbolic back door leading to a windowed bay that faces Heinz Chapel alludes to a door in the Myeong-nyudang which leads to the Sungkyunkwan's courtyard.
The south wall displays three documents that explain the letters and principles of the Hangul, or Korean alphabet, which was created by the court of Sejong the Great in 1443. A display niche to the right of the classrooms blackboards contains a book illustrating Crown Prince Hyomyeong's matriculation to Sungkyunkwan in 1817, while another niche displays the Four Treasures of the Study: brush, ink, paper and ink-stone. Furnishings include freestanding, hard-oak desks by Korean designer Ji-hoon Ha that accommodate two to three students and are specifically designed for laptops. The room also contains an 85-inch, 3-D LED screen and central speaker system and is the first nationality room to be constructed with such technology.
Lithuanian The Lithuanian Classroom is dominated by a fresco depicting Mikalojus Konstantinas Čiurlionis' famous painting The Two Kings portrays the reverence Lithuanians have for their villages. This mural sets the tone for a room that pays tribute to the symbolism and love of nature and home reflected in Lithuanian folk art. The door's wooden planks are laid in a diamond pattern similar to those of many farm structures. At the center of the door is a carved rosette, symbol of fire. Above the entrance, a stylized sun between two horses' heads represents light and sound believed to ward off evil spirits.
The white oak molding of intersecting scallops resembles decorations found on farm granaries or kleitis. Names of famous Lithuanians are carved on the frieze above the blackboard. The wall fabric is linen woven in a design called "The Path of the Birds." Its frame is of white oak and rare bog oak that acquires its deep hue while submerged in a marshy bog for decades. Lithuanian farmers would thus preserve prime trees in order to make furniture pieces that were treasured as heirlooms. The professor's desk is modeled after a household table and the lectern incorporates details of a spinning wheel spindle.
Student chairs are carved with a design found on household utensils. The radiator enclosure is perforated with a design of wild rue leaves, a Lithuanian national emblem. Traditionally, a bride is crowned with a wreath of rue, symbol of chastity. Windows of handpressed glass bear leaded medallions in the form of sun ornaments often found on roadside shrines. Norwegian The Norwegian Classroom was designed in Oslo in an 18th-century peasant style using Norwegian building techniques, painted decoration, and craftsmanship by architect Georg Eliassen just prior to the outbreak of World War II. Plans for the room were sent on the last ship to leave Petsamo for the United States where they were completed by University Architect Albert A. Klimcheck.
Walls of the main space are paneled with vertical overlapping spruce boards hand-rubbed with wax. The walls in the front of the room are painted a soft blue and decorated with floral designs reminiscent of the 18th century rosemaling technique. Because living and bedrooms were often merged into one room during this era, two of the panels swing open as if they would reveal traditional built-in-beds, but instead conceal the blackboard. The room features high-sloped ceilings reflective of those in Nordic peasant homes that keep snow from accumulating during the severe winters. Spruce boards are laid in a herringbone pattern slanting upward to a plane of flat boards decorated by two hand-carved, painted rosettes with a symbol for the midnight sun.
Wooden chandeliers bearing a painted design incorporating "1945", the year the room was opened, hang from the flat surfaces. The professor's section of the room has a low raftered ceiling. The transition between the two parts of the room is indicated by a corner kleberstone fireplace in which birch logs were burned standing on end to assure that smoke would rise up the chimney. Windows are of handmade opalescent glass tinted pale yellow. Since a bay window is not a Scandinavian tradition, the area is plastered, paved with slate, and treated as a traditional alcove. The student tablet armchairs are low-backed and the professor's chair is of a typical Viking design with carved heads of beasts and an intertwining dragon motif that traditionally serves as a symbol that protects against evil.
The room features a century-old grandfather clock with an engraved dial and a case that is painted to match the wall decorations of the smaller room. Above the rear wall bench and flanked by corner display cabinets decorated with rosemaling, hangs a framed copy of a 1695 Norwegian woolen tapestry depicting the Biblical parable of the five wise and five foolish virgins Philippine The Philippine Nationality Room began construction in May 3, 2018, overcoming a prior hold on the project since 2011. The design of the Philippine room is based on a traditional bahay na bato. Meaning "house of stone," bahay na bato is a long-lasting type of home that became popular in the Philippines during the years of Spanish occupation (mid-1500s and late 1800s).
The room is particularly based on the interiors of the Quema House in the city of Vigan. The Philippine Nationality Room was designed by Pittsburgh architect Warren Bulseco and Philippine architect Melinda Minerva “Popi” Laudico. Professor Fernando Zialcita, a noted authority on Philippine ancestral houses from Ateneo de Manila University, served as adviser to the project. Filipino-American artist Eliseo Art Silva created paintings for the room. The room features lattice-patterned capiz shell windows, a popular alternative to glass in the Philippines due to frequent typhoons. The chairs are backed with solihiya, rattan woven into a sunburst pattern. An etched silver Murano mirror from Europe and a bronze chandelier from the United States highlight the role of imported design in Filipino culture.
Other artifacts showcase pre-Colonial cultures. The Golden Tara is a Hindu sculpture viewed by the Manobo tribe as a protective nature spirit. The Manunggul Jar, excavated from a Neolithic burial site in Palawan, depicts human figures traveling in a boat to the afterlife. The room's ceremonial key, designed by Christopher Purpura, incorporates mythological figures from the Meranao people of Mindanao—the serpent Naga and the bird Sarimanok. Polish The Polish Classroom was inspired by rooms in Cracow's Wawel Castle, for centuries the residence of kings. The Polish astronomer Nicolaus Copernicus, and the science that his theories revolutionized, are also a major theme of the room.
A replica of the famous Jan Matejko portrait of Copernicus shows him as a young man pursuing his study of the universe from a workshop on the roof of his uncle's house in Allenstein (Olsztyn). In the bay stands an enlarged replica of the 16th-century Jagiellonian globe, one of the oldest existing globes to depict North America as a separate continent. The original globe was only eight inches high and was designed to operate as a clock and calendar. It took a metalsmith in Cracow five years to complete the large globe in this room. Artists from Cracow also came to Pittsburgh to paint the ceiling of beams with informal geometric Renaissance decorations.
The room is illuminated by a bronze chandelier bearing a stylized Polish eagle. The walnut seminar table was copied from one in a state dining room at Wawel Castle. The windows combine hexagonal handmade roundels, similar to those in Wawel Castle, with stained-glass coats of arms representing Polish institutions of higher education. The cornerstone is a fragment of Gothic cornice preserved from the Collegium Maius (1369), the ancient Jagiellonian Library. Poland's music is represented by the original manuscript of Ignace Paderewski's only opera, Manru, which is displayed in the archive cabinet. Romanian The Romanian Classroom was designed in Bucharest by Nicolae Ghica-Budeşti.
The carved doorframe is characteristic of stone thresholds of Romanian monasteries and is made is of American limestone selected due to its similarity to Romanian limestone used in the royal palace at Bucharest. The entrance door of the Romanian Classroom is ornately carved oak reminiscent of Byzantine churches in Romania. The words of Vasile Alecsandri, one of the greatest Romanian poets of the 19th century, are carved overhead in the stone door frame from his Ode to the Year 1855: "The Romanian is like the mighty rock which amidst the waves of the stormy and majestic sea forever remains unmoved."
The floor is laid in square blocks of pink marble imported from quarries at Ruşchiţa. The black boards are set in arched oak panels, carved in a manner of icon screens in Eastern Orthodox and Greek Catholic Romanian churches. These are separated by carved-twisted rope which suggests the Roman origin of many of Romania's artistic traditions. Ancient original icons from Romania depicting the Virgin and Child, Christ, the Dormition of the Virgin, and Saint Mark are embedded in the upper section of each panel. White arca paint mixed with color gives the smooth plastered walls a bluish pink tint. A Byzantine-style mosaic embedded in the rear wall, a gift of the Romanian government, was executed by Bucharest ceramicist Nora Steriade in gold, turquoise, bronze, ruby red, and black pieces of glass, and was originally part of the Romanian Pavilion at the 1939 New York World's Fair.
The lettering for the inscription and for the entrance text is the work of Alexander Seceni. The mosaic depicts Constantin Brâncoveanu, Prince of Wallachia, who refused to recant the Christian faith even at the cost of his own life and the lives of the male members of his family. The six windows have rounded Romanesque heads reflecting tradition brought from Rome when they conquered the original Dacian settlers in 106 AD. Two small window casements are deeply recessed and have marble window ledges. The four large center windows, form an alcove shut off from the main part of the room by an iron grilled gates wrought in Romania and hung in an arch.
These gates swing back in folded sections against the plastered wall. A slab of polished marble tops the wrought-iron radiator grille. Yellow silk draperies frame the windows and ancient icons befitting the season and holidays are exhibited in the alcove which is reminiscent of an icon shrine in an Orthodox Church. The student chairs are of dark oak hand-carved by Romanian peasant artisans using simple pocketknives and each splat bears a different design. The professor's reading desk was adapted from an Eastern Orthodox Church lectern. Russian The Russian Classroom contains folk ornamentation with traditional motifs from Byzantium, the spiritual center of Russia.
The seminar table is made of oak slabs matched in contrasting grain and held together by ornamental keys. The cut-out apron is characteristic of massive tables in the Vologda district. The back of each student's chair has a cruciform circle pattern surmounted by triangles carved with symbols of regional or stylistic significance including the reindeer which symbolizes the tundra and the sturgeon that represents the Volga River. The professor's chair has a back of spirals surmounted by two peacocks worshipping the tree of life. The podium is ecclesiastic in character and suggests the analoi used in Orthodox churches to support heavy Bibles.
The blackboard is patterned after a triptych, or three-leafed frame which holds icons. The doors of the blackboard are a grille of wooden spirals backed by red velvet. Above them is a carved panel with Sirin and Alcanost, the twin birds of Russian folklore that depict joy and sorrow as indistinguishable. A dado or low wainscot of simple horizontal oaken boards surrounds the room and incorporates the blackboard, the corner cupboard, and kiot which is a Slavic term for a wall frame treated as a piece of furniture. Within the kiot hangs an vishivka (appliqué and embroidery) banner of Saint George, patron saint of Moscow since the 15th century.
The banner was made with pieces of 16th and 17th century fabric from Venice and Paris and is an example of needlework once popular with the Russian aristocracy. The words "Valorous youth victorious over forces of evil and darkness" are carved in both Russian and English below the banner. A copy of the Avinoff family icon in the room depicts the miraculous saving of the city of Kitej from a Tartar invasion in the 14th century. The ceiling is cornered with designs resembling those used to form traditional Easter cakes and which symbolize the four seasons, with a bud for Spring, a sunflower for summer, grapes for Autumn, and a pine cone for Winter.
A wrought iron chandelier was created by Russian-born Hyman Blum. Following a visit from Dmitry Medvedev in 2009, a display cabinet with carved ornamentation matching the rooms original carvings was installed to house three gifts presented by the then Russian President. Scottish The Scottish Classroom was designed by Reginald Fairlie of Edinburgh in the period style of the early 17th century. The woodwork is carefully selected and treated English pollard oak. The names of distinguished Scots are carved in the ribbon bands of the panels and include David Livingstone who was an African missionary and explorer, Robert Louis Stevenson who authored Treasure Island, and Alexander Fleming who discovered penicillin.
The inscriptions above the doors and the rear cabinet are from "The Brus" by the 14th-century Scottish poet John Barbour. The room's oak doors were copied from the entrance of Rowallan Castle in Ayrshire. A 16th-century Scottish proverb above the blackboard was taken from the Cowgate in Edinburgh and is known as "the Scottish Golden Rule" which reads: "Gif Ye did as Ye sould Ye might haif as Ye would." The plaster frieze was adapted from the plaster frieze at Elcho Castle in Perthshire and incorporates symbols of 14 Scottish clans which had members on the room committee, such as the buckle of the Leslie Clan.
The thistle, Scotland's national flower, is rendered on the cornerstone as a tree-of-life. The overmantel of the Scottish sandstone fireplace that is flanked by carved kists, or log storage chests, is dominated by a portrait of poet Robert Burns that is copied from an original by Alexander Nasmyth which hangs in the National Portrait Gallery of Scotland. Above the portrait is the cross of St. Andrew, Scotland's patron saint. The bronze statuettes on the mantel near an arrangement of dried heather are miniature replicas of heroic statues at the gateway to Edinburgh Castle and represent the 13th-century patriot Sir William Wallace and the 14th century freedom fighter, Robert the Bruce, both of whom were popularized in the movie Braveheart.
Medallions in the bay windows represent the coats of arms of the four ancient Scottish universities: Glasgow, St. Andrew's, Aberdeen, and Edinburgh. The medallions in the front and rear windows are of Elgin and Melrose Abbeys which were 13th and 16th century seats of learning. The draperies are of crewel-embroidered linen. The rooms lighting fixtures were inspired by an iron coronet in Edinburgh's John Knox Museum that was retrieved from the battlefield of Bannockburn at which Scotland won its independence from England in 1314. Student's seats resemble a chair that belonged to John Knox. An old Scottish church furnished the pattern for the reading stand.
The rear cabinet, based on an aumbry or weapon closet, contain artifacts such as pewter and china used at Soutar's Inn in Ayrshire that was frequented by Robert Burns. The panels in the doors, mantel, and in-the-wall cabinets were carved in Edinburgh by Thomas Good and then shipped to Pittsburgh. The cabinetwork was done in the shops of Gustav Ketterer of Philadelphia. Wrought ironwork was done by Samuel Yellin. Cut into stone above the doorways are the thistle and the Lion Rampant, the Scottish emblem incorporated into Britain's royal arms. The chairman of the original Scottish Classroom Committee was Jock Sutherland.
Swedish The Swedish Classroom reflects a peasant cottage and contains murals painted by Olle Nordmark. The special glory of the room is the rear wall paintings. The inspiration for the four framed paintings came from painted panels done by the 18th-century painter from Hälsingland, Gustav Reuter. Linton Wilson found the panels at the Nordic Museum. The hooded brick fireplace derives from an original in the Bollnäs Cottage in Skansen, the famous outdoor museum in Stockholm. The brilliant white walls and fireplace are constructed of 200-year-old handmade bricks. The fire tools were handwrought by Ola Nilsson, a Swedish blacksmith. He reconstructed tools used in his childhood home in Sweden.
A subtle sense of humor associated with the Swedish people is revealed in the room's paintings. A wall fresco secco depicts the Three Wise Men dressed as cavaliers riding to Bethlehem, in two directions. In their midst is Sweden's patron saint, St. Catherine. The sloped ceiling bears decorations in which the central figure is the Archangel Gabriel, seen as a droll trumpeter with two left feet. Nearby are renditions of Justice and Knowledge surrounded by groupings of flowers. Justice uses her blindfold to hold scales that appear balanced but have an off-center fulcrum. Knowledge seems puzzled as she contemplates writing on her slate with a quill pen.
Furniture and woodwork are the work of Erik Jansson of Philadelphia. The classroom's oak furniture is stained a muted gray-blue tone, similar to that found in old Swedish homes. Floral designs, in colors that complement the amber tone of fir wall benches, brighten the door and archive cabinet. The red brick floor is set in a herringbone pattern. Swiss The Swiss Classroom is modeled after a 15th-century room from Fraumunster Abbey displayed in the Swiss National Museum in Zurich, Switzerland. The room is paneled in pine wood and features four white oak trestle tables and four display cases that represent the four languages of Switzerland: French, German, Italian, and Romansch.
26 country-style chairs contain painted carvings of the symbols of Switzerland's cantons that form the Swiss Confederation which united in 1291. The furniture and woodwork were crafted by Richard Sink of French Creek, WV. A centerpiece of the room is a reproduction of a cocklestove that is modeled on a H.H. Graaf family oven on display in Schloss Wülflingen Castle, Winterthur. The cocklestove's ornate tiles contain several painted Swiss motifs that including various animals, plants, edelweiss, the heraldic emblem of the Graaf family, and a depiction of the Swiss legend of William Tell. Windows are leaded and feature three stained-glass shields of the original Swiss cantons as well as the Swiss Cross.
The Swiss Cross is also displayed stone over the door, within the window of the door, and on the lectern which is modeled on a 17th-century schoolmaster's desk. A carved and painted frieze depicts Swiss flora and fauna and an antique map depicts Switzerland by its ancient Latin name of "Helvetia". Portraits on the back wall, done in the style of Hans Holbein the Younger, depict Jean-Jacques Rousseau and Johann Heinrich Pestalozzi. Wood beamed ceiling contains LED lights that are hidden behind rosettes. Syrian-Lebanon Originally a library built in 1782 in a wealthy Damascan merchant's home, the Syria-Lebanon Room was moved intact to its location in the Cathedral of Learning following a six-year effort to fund and install the room by the Syrian and Lebanese communities in Pittsburgh.
Because of the fragility and pricelessness of the furnishing, it has been closed for class use and is one of two display rooms. The linden-paneled walls and ceilings are decorated with “gesso painting,” a mixture of chalk and glue applied by brush in intricate relief, then painted and overlaid with silver and gold leaf. The room features a (now improperly oriented) mihrab with a stalactite vault traditionally housing the Koran and prayer rug. Set in the walls are book cabinets and display shelves. The room is illuminated by an old mosque lamp of perforated copper with handblown glass wells that originally held oil, water, and wicks.
The sofas, from the Arabic word "suffah", are covered in satin and rest on a dark red and white marble foundation. The marble floor slopes down at the entrance where visitors would remove their shoes before entering. In 1997, a glass-paneled French-style door to the room was added to allow the room to be visible from passers-by. The doors were patterned after a grille design found on the windows of the 18th century Ibn Room in the Islamic section of the Metropolitan Museum in New York City. Turkish The Turkish Nationality Room was based on a baş odası, or main room, of a typical Turkish house or hayat with an outer gallery and a side iwan.
The iwan is intended to be used as an entrance area similar to the royal pavilion, annexed to the Yeni Mosque in the Eminönü district of Istanbul, which was built in 1663 for the use of Sultan Mehmet IV. In the iwan of the Turkish Nationality Room, four ceramic panels, painted on clay tiles in Ankara, represent various cultures and points in Turkish history. The largest ceramic is a portrait of Mustafa Kemal Ataturk, the founder and first president of the Republic of Turkey, who is depicted instructing the nation on the Turkish alphabet adopted in 1928.
Other panels depict Uighur princesses, who represent the importance of women in circa 9th-century Turkish culture, a reproduction of "Two merchants in conversation" by Mehmed Siyah Kalem which signifies the appearance of realism in Turkish drawing around the 14th century; and a depiction of Suleiman the Magnificent at the circumcision ceremony of Şehzade Beyazıt and Şehzade Cihangir which represents the apex of Ottoman power and culture in the 16th century. The main room attempts to convey the theme of democracy with its seating distributed around the perimeter of the room which suggests that all occupants are equals. Hardwood seats mimic divan-style seating found in a typical baş odası with back panels that function as writing tablets which when retracted form a "parted curtain" motif, a common shape used for household wall niches.
The room's ceiling, modeled after the Emirhocazade Ahmet Bey summer house in Safranbolu, is a combination of traditional çitakâri and kündekâri carpentry art that creates intricate geometric patterns using small pieces of wood attached without metal fasteners or glue. Clear glass windows along one wall frame a painted mural depicting a panoramic view of Istanbul which is feature similar to that seen in the mirrored room of the Topkapi Palace. The stained glass windows depict a tulip shape which served as a symbol of the Ottomans in the 18th century. Display cases contain historic examples of Turkish calligraphy, ceramics, jewelry, miniatures and textiles as well as an evil eye.
The entrance symbol above the exterior door depicts the current flag of Turkey, adopted in 1936. Ukrainian The Ukrainian Classroom is designed in Baroque style with richly carved wood, colorful ceramics, and intricate metalwork in this adaptation of a nobleman's reception room. The entrance has an archaic trapezoidal form with carved motifs of water (chevron), wheat, and sunflowers. The lintel inscription commemorates Ukraine's millennium of Christianity (988–1988). The stove tiles depict festival practices and daily life. A pokutia, or place of honor, is defined by the benches and the traditional icons of St. Nicholas, the Mother of God, Christ the Teacher, and St. George.
The chalkboard doors bearing the Tree of Life are surmounted by three Cyrillic alphabets used in Ukraine in the 11th, 17th, and 19th centuries. On the right wall, a copper bas-relief depicts the development of Ukrainian culture over the millennia. It portrays cultural centers, historical figures, rituals, monuments, and the evolution of Ukrainian ornament. The massive crossbeam's elaborate carvings include a protective solar symbol and a quotation from Ukraine's bard Taras Shevchenko (1814–1861): "Learn, my brothers! Think and read ... Learn foreign thoughts, but do not shun your own country!" Beyond the wood posts, reminiscent of a gallery, the display case houses traditional Ukrainian art and crafts.
Welsh The Welsh Classroom, was perhaps the longest in coming, as reservations for a Welsh room were originally requested in the 1930s. The existing room, installed on the third floor of the Cathedral of Learning, is patterned after the Pen-rhiw Chapel at St Fagans National History Museum near Cardiff and represents a traditional 18th-century Welsh capel, or chapel, which often became the center of village social life. By this period, the English ruled the country and imposed law requiring English as the official language of the courts and churches. In order to worship and hold church services in their native Welsh language, and spurred on by the non-conformist movement started by the Protestant Reformation, the Welsh people met in secret locations such as barns or homes, as suggested by the simple white walled capel modeled in this Nationality Room.
The minister would live at one end as depicted by the display case with dishes and pottery that would be found in a Welsh kitchen and the long oak case clock seated on a Welsh slate foundation opposite the main blue door. The clock, considered one of the most important furnishings in a Welsh home, has, instead of numbers, a painted square face that spells out "Richard Thomas" suggesting that he was both the maker and owner of the clock. The bay window serves as the focus of the Welsh chapel worship, including a blue raised pulpit with a view of the entire congregation and two Deacon's benches from which to monitor the actions of the minister and congregation.
At the other end of the room is a table bearing a lectern, as such worship places would often become a school room for both children and adults during week days. Above the chalk board is the Lord's Prayer, written in Welsh. Pew benches of pine face the lectern. Along the wall, larger and more comfortable blue-painted pew boxes with wooden floors, often also serving as barn cattle stalls, would have served wealthier families who would sometimes bring straw, blankets, hot bricks, or dogs to keep them warm. To reflect the simplicity of such meeting places, the ceiling beams are made of poplar and flooring suggests a typical capel dirt floor.
The carved stone dragon over the doorway, the long-time Welsh national symbol, represents the legendary victory of the Red Dragon over the White Dragon of numerous tales of medieval Wales and represents the triumph of Good over Evil. Yugoslav The Yugoslav Classroom was designed by Professor Vojta Braniš, a sculptor and director of the Industrial Art School in Zagreb. The walls are paneled in Slavonian oak and hand-carved with geometric figures and the old Slavonic heart design which is combined with a running geometric border, a favorite with South Slavs. This type of work, known as "notch-carving", was traditionally done with a penknife as pastime of peasants.
On the corridor wall is a specially designed coat of arms featuring a double-headed eagle symbolizing the religious influences of Eastern Empire of Byzantium and Western Empire of Rome along with the founding dates of the universities in Belgrade, Ljubljana, and Zagreb. The ceiling is carved with intricate Croatian, Slovenian, and Serbian folk motifs and the wooden chandeliers are similar to those in the White Palace in Belgrade. The professor's chair and guests chairs were carved by students at the International Art School in Zagreb, and each spindle of the chairs bears a different notched design. At the window, a bronze sculpture by Vojta Braniš, "Post-War Motherhood", depicts a barefoot mother nursing her child whom she has protected during the long months of war.
In the display cabinet is a lace portrayal of the Madonna of Brežje by Slovenes Leopoldina Pelhan and her student Mila Božičkova which took six months to complete and was inspired by the story of a lace Madonna created by the villagers of Sveta Gora in order to replace a priceless painting during World War I. The ceiling squares contain one of the three alternating ceiling ornaments suggesting flowers, stars, the sun, and other radiating geometric patterns, which are organized into a matrix of 9 by 7 squares. Above the paneled walls, six portraits depict prominent Yugoslavs.
On the front wall are portraits of Vuk Stefanović Karadžić (1787–1864) who compiled the Serbian dictionary and collected, edited, and published Serbian national ballads and folk songs; and Croatian statesman Bishop Josip Juraj Strossmayer (1815–1905) who was known for his efforts to achieve understanding between the Roman Catholic and Greek Orthodox churches, founder of the Yugoslav Academy of Sciences and Arts (now the Croatian Academy of Sciences and Arts). On the corridor wall are likenesses of Baron George von Vega (1754–1802), a Slovenian officer in the Austrian army and mathematician recognized for various works including a book of logarithm tables; and Petar Petrović Njegoš (1813–1851), the last prince-bishop of Montenegro, who was celebrated for his poetry.
Represented on the rear wall are Rugjer Bošković (1711–1787), a Croatian scientist distinguished for his achievements in the fields of mathematics, optics, and astronomy; and France Ksaver Prešeren (1800–1849) who is considered one of the greatest native-language Slovenian poets. The Yugoslav Classroom's Executive Committee was first organized in 1926 under the chairmanship of Anton Gazdić, the president of the Croatian Fraternal Union. After his death in September 1933 the new chairman was Steve Babić, the previous vice-chairman, and the new vice-chairwoman became Catherine Rušković McAleer. Famous Croatian sculptor Ivan Meštrović was a great supporter of the Classroom and gave two of his works to the University, one a bust of Mihajlo Pupin and the other a self-portrait.
The Classroom was designed to portray the culture and traditions of the Yugoslavs, who were considered as inhabitants of the various Yugoslavian regions: Croatians, Dalmatians, Slavonians, Slovenians, Serbians, Bosnians and Montenegrins. Proposed rooms The University has two additional Nationality Room Committees which are in various stages of fund raising and room design. Proposed rooms include the following: Finnish Iranian Moroccan Thai Prior projects for Danish and Latin American and Caribbean rooms have been discontinued. Gallery References Further reading Bruhns, E. Maxine, Heritage Room Design Guidelines, July 2001 Brown, Mark.
The Cathedral of Learning: Concept, Design, Construction, University of Pittsburgh Nationality Rooms Program Bowman, John G. Unofficial Notes Nationality Rooms Guide Training Material University of Pittsburgh website: About the Nationality Rooms External links Nationality Rooms web site Nationality Rooms Virtual Tour Nationality Rooms and Intercultural Exchange Program Scholarships Video Cathedral of Learning feature on John Ratzenberger's Made in America WQED OnQ: E. Maxine Bruhns & The Nationality Rooms Gigpans African Heritage Nationality Room Austrian Nationality Room English Nationality Room Welsh Nationality Room Room committees African Heritage Classroom & Committee Austrian American Cultural Society of Pittsburgh: Austrian Nationality Room Danish American Society The Finlandia Foundation, Pittsburgh Chapter Korean Heritage Room Committee Latin American & Caribbean Heritage Room Filipino American Association of Pittsburgh: Philippine Nationality Room Swiss-American Society of Pittsburgh Turkish Nationality Room St. David's Society of Pittsburgh (Welsh Nationality Room Committee) Category:Individual rooms Category:University of Pittsburgh Category:Tourist attractions in Pittsburgh Category:University and college buildings on the National Register of Historic Places in Pennsylvania Category:Museums in Pittsburgh Category:Pittsburgh History & Landmarks Foundation Historic Landmarks Category:University museums in Pennsylvania Category:Ethnic museums in Pennsylvania Category:Dacia in art Category:National Register of Historic Places in Pittsburgh Category:Individually listed contributing properties to historic districts on the National Register in Pennsylvania Category:Historic district contributing properties in Pennsylvania
An S-type star (or just S star) is a cool giant with approximately equal quantities of carbon and oxygen in its atmosphere. The class was originally defined in 1922 by Paul Merrill for stars with unusual absorption lines and molecular bands now known to be due to s-process elements. The bands of zirconium monoxide (ZrO) are a defining feature of the S stars. The carbon stars have more carbon than oxygen in their atmospheres. In most stars, such as class M giants, the atmosphere is richer in oxygen than carbon and they are referred to as oxygen-rich stars. S-type stars are intermediate between carbon stars and normal giants.
They can be grouped into two classes: intrinsic S stars, which owe their spectra to convection of fusion products and s-process elements to the surface; and extrinsic S stars, which are formed through mass transfer in a binary system. The intrinsic S-type stars are on the most luminous portion of the asymptotic giant branch, a stage of their lives lasting less than a million years. Many are long period variable stars. The extrinsic S stars are less luminous and longer-lived, often smaller-amplitude semiregular or irregular variables. S stars are relatively rare, with intrinsic S stars forming less than 10% of asymptotic giant branch stars of comparable luminosity, while extrinsic S stars form an even smaller proportion of all red giants.
Spectral features Cool stars, particularly class M, show molecular bands, with titanium(II) oxide (TiO) especially strong. A small proportion of these cool stars also show correspondingly strong bands of zirconium oxide (ZrO). The existence of clearly detectable ZrO bands in visual spectra is the definition of an S-type star. The main ZrO series are: α series, in the blue at 464.06 nm, 462.61 nm, and 461.98 nm β series, in the yellow at 555.17 nm and 571.81 nm γ series, in the red at 647.4 nm, 634.5 nm, and 622.9 nm The original definition of an S star was that the ZrO bands should be easily detectable on low dispersion photographic spectral plates, but more modern spectra allow identification of many stars with much weaker ZrO.
MS stars, intermediate with normal class M stars, have barely detectable ZrO but otherwise normal class M spectra. SC stars, intermediate with carbon stars, have weak or undetectable ZrO, but strong sodium D lines and detectable but weak C2 bands. S star spectra also show other differences to those of normal M class giants. The characteristic TiO bands of cool giants are weakened in most S stars, compared to M stars of similar temperature, and completely absent in some. Features related to s-process isotopes such as YO bands, Sr lines, Ba lines, and LaO bands, and also sodium D lines are all much stronger.
However, VO bands are absent or very weak. The existence of spectral lines from the period 5 element Technetium (Tc) is also expected as a result of the s-process neutron capture, but a substantial fraction of S stars show no sign of Tc. Stars with strong Tc lines are sometimes referred to as Technetium stars, and they can be of class M, S, C, or the intermediate MS and SC. Some S stars, especially Mira variables, show strong hydrogen emission lines. The Hβ emission is often unusually strong compared to other lines of the Balmer series in a normal M star, but this is due to the weakness of the TiO band that would otherwise dilute the Hβ emission.
Classification schemes The spectral class S was first defined in 1922 to represent a number of long-period variables (meaning Mira variables) and stars with similar peculiar spectra. Many of the absorption lines in the spectra were recognised as unusual, but their associated elements were not known. The absorption bands now recognised as due to ZrO are clearly listed as major features of the S-type spectra. At that time, class M was not divided into numeric sub-classes, but into Ma, Mb, Mc, and Md. The new class S was simply left as either S or Se depending on the existence of emission lines.
It was considered that the Se stars were all LPVs and the S stars were non-variable, but exceptions have since been found. For example, π1 Gruis is now known to be a semiregular variable. The classification of S stars has been revised several times since its first introduction, to reflect advances in the resolution of available spectra, the discovery of greater numbers of S-type stars, and better understanding of the relationships between the various cool luminous giant spectral types. Comma notation The formalisation of S star classification in 1954 introduced a two-dimensional scheme of the form SX,Y. For example, R Andromedae is listed as S6,6e.
X is the temperature class. It is a digit between 1 (although the smallest type actually listed is S1.5) and 9, intended to represent a temperature scale corresponding approximately to the sequence of M1 to M9. The temperature class is actually calculated by estimating intensities for the ZrO and TiO bands, then summing the larger intensity with half the smaller intensity. Y is the abundance class. It is also a digit between 1 and 9, assigned by multiplying the ratio of ZrO and TiO bands by the temperature class.
This calculation generally yields a number which can be rounded down to give the abundance class digit, but this is modified for higher values: 6.0 – 7.5 maps to 6 7.6 – 9.9 maps to 7 10.0 – 50 maps to 8 > 50 maps to 9 In practice, spectral types for new stars would be assigned by referencing to the standard stars, since the intensity values are subjective and would be impossible to reproduce from spectra taken under different conditions. A number of drawbacks came to light as S stars were studied more closely and the mechanisms behind the spectra came to be understood.
The strengths of the ZrO and TiO are influenced both by temperature and by actual abundances. The S stars represent a continuum from having oxygen slightly more abundant than carbon to carbon being slightly more abundant than oxygen. When carbon becomes more abundant than oxygen, the free oxygen is rapidly bound into CO and abundances of ZrO and TiO drop dramatically, making them a poor indicator in some stars. The abundance class also becomes unusable for stars with more carbon than oxygen in their atmospheres. This form of spectral type is a common type seen for S stars, possibly still the most common form.
Elemental intensities The first major revision of the classification for S stars completely abandons the single-digit abundance class in favour of explicit abundance intensities for Zr and Ti. So R And is listed, at a normal maximum, with a spectral type of S5e Zr5 Ti2. In 1979 Ake defined an abundance index based on the ZrO, TiO, and YO band intensities. This single digit between 1 and 7 was intended to represent the transition from MS stars through increasing C/O ratios to SC stars. Spectral types were still listed with explicit Zr and Ti intensity values, and the abundance index was included separately in the list of standard stars.
Slash notation The abundance index was immediately adopted and extended to run from 1 to 10, differentiating abundances in SC stars. It was now quoted as part of the spectral type in preference to separate Zr and Ti abundances. To distinguish it from the earlier abandoned abundance class it was used with a slash character after the temperature class, so that the spectral class for R And became S5/4.5e. The new abundance index is not calculated directly, but is assigned from the relative strengths of a number of spectral features. It is designed to closely indicate the sequence of C/O ratios from below 0.95 to about 1.1.
Primarily the relative strength of ZrO and TiO bands forms a sequence from MS stars to abundance index 1 through 6. Abundance indices 7 to 10 are the SC stars and ZrO is weak or absent so the relative strength of the sodium D lines and Cs bands is used. Abundance index 0 is not used, and abundance index 10 is equivalent to a carbon star Cx,2 so it is also never seen. The derivation of the temperature class is also refined, to use line ratios in addition to the total ZrO and TiO strength. For MS stars and those with abundance index 1 or 2, the same TiO band strength criteria as for M stars can be applied.
Ratios of different ZrO bands at 530.5 nm and 555.1 nm are useful with abundance indices 3 and 4, and the sudden appearance of LaO bands at cooler temperatures. The ratio of Ba and Sr lines is also useful at the same indices and for carbon-rich stars with abundance index 7 to 9. Where ZrO and TiO are weak or absent the ratio of the blended features at 645.6 nm and 645.0 nm can be used to assign the temperature class. Asterisk notation With the different classification schemes and the difficulties of assigning a consistent class across the whole range of MS, S, and SC stars, other schemes are sometimes used.
For example, one survey of new S/MS, carbon, and SC stars uses a two-dimensional scheme indicated by an asterisk, for example S5*3. The first digit is based on TiO strength to approximate the class M sequence, and the second is based solely on ZrO strength. Standard stars This table shows the spectral types of a number of well-known S stars as they were classified at various times. Most of the stars are variable, usually of the Mira type. Where possible the table shows the type at maximum brightness, but several of the Ake types in particular are not at maximum brightness and so have a later type.
ZrO and TiO band intensities are also shown if they are published (an x indicates that no bands were found). If the abundances are part of the formal spectral type then the abundance index is shown. Formation There are two distinct classes of S-type stars: intrinsic S stars; and extrinsic S stars. The presence of Technetium is used to distinguish the two classes, only being found in the intrinsic S-type stars. Intrinsic S stars Intrinsic S-type stars are thermal pulsing asymptotic giant branch (TP-AGB) stars. AGB stars have inert carbon-oxygen cores and undergo fusion both in an inner helium shell and an outer hydrogen shell.
They are large cool M class giants. The thermal pulses, created by flashes from the helium shell, cause strong convection within the upper layers of the star. These pulses become stronger as the star evolves and in sufficiently massive stars the convection becomes deep enough to dredge up fusion products from the region between the two shells to the surface. These fusion products include carbon and s-process elements. The s-process elements include zirconium (Zr), yttrium (Y), lanthanum (La), technetium (Tc), barium (Ba), and strontium (Sr), which form the characteristic S class spectrum with ZrO, YO, and LaO bands, as well as Tc, Sr, and Ba lines.
The atmosphere of S stars has a carbon to oxygen ratio in the range 0.5 to < 1. Carbon enrichment continues with subsequent thermal pulses until the carbon abundance exceeds the oxygen abundance, at which point the oxygen in the atmosphere is rapidly locked into CO and formation of the oxides diminishes. These stars show intermediate SC spectra and further carbon enrichment leads to a carbon star. Extrinsic S stars The Technetium isotope produced by neutron capture in the s-process is 99Tc and it has a half life of around 200,000 years in a stellar atmosphere.
Any of the isotope present when a star formed would have completely decayed by the time it became a giant, and any newly formed 99Tc dredged up in an AGB star would survive until the end of the AGB phase, making it difficult for a red giant to have other s-process elements in its atmosphere without technetium. S-type stars without technetium form by the transfer of technetium-rich matter, as well as other dredged-up elements, from an intrinsic S star in a binary system onto a smaller less-evolved companion. After a few hundred thousand years, the 99Tc will have decayed and a technetium-free star enriched with carbon and other s-process elements will remain.
When this star is, or becomes, a G or K type red giant, it will be classified as a Barium star. When it evolves to temperatures cool enough for ZrO absorption bands to show in the spectrum, approximately M class, it will be classified as an S-type star. These stars are called extrinsic S stars. Distribution and numbers Stars with a spectral class of S only form under a narrow range of conditions and they are uncommon. The distributions and properties of intrinsic and extrinsic S stars are different, reflecting their different modes of formation. TP-AGB stars are difficult to identify reliably in large surveys, but counts of normal M-class luminous AGB stars and similar S-type and carbon stars have shown different distributions in the galaxy.
S stars are distributed in a similar way to carbon stars, but there are only around a third as many as the carbon stars. Both types of carbon-rich star are very rare near to the galactic centre, but make up 10% – 20% of all the luminous AGB stars in the solar neighbourhood, so that S stars are around 5% of the AGB stars. The carbon-rich stars are also concentrated more closely in the galactic plane. S-type stars make up a disproportionate number of Mira variables, 7% in one survey compared to 3% of all AGB stars. Extrinsic S stars are not on the TP-AGB, but are red giant branch stars or early AGB stars.
Their numbers and distribution are uncertain. They have been estimated to make up between 30% and 70% of all S-type stars, although only a tiny fraction of all red giant branch stars. They are less strongly concentrated in the galactic disc, indicating that they are from an older population of stars than the intrinsic group. Properties Very few intrinsic S stars have had their mass directly measured using a binary orbit, although their masses have been estimated using Mira period-mass relations or pulsations properties. The observed masses were found to be around until very recently when Gaia parallaxes helped discover intrinsic S stars with solar-like masses and metallicities.
Models of TP-AGB evolution show that the third dredge-up becomes larger as the shells move towards the surface, and that less massive stars experience fewer dredge-ups before leaving the AGB. Stars with masses of will experience enough dredge-ups to become carbon stars, but they will be large events and the star will usually skip straight past the crucial C/O ratio near 1 without becoming an S-type star. More massive stars reach equal levels of carbon and oxygen gradually during several small dredge-ups. Stars more than about experience hot bottom burning (the burning of carbon at the base of the convective envelope) which prevents them becoming carbon stars, but they may still become S-type stars before reverting to an oxygen-rich state.
Extrinsic S stars are always in binary systems and their calculated masses are around . This is consistent with RGB stars or early AGB stars. Intrinsic S stars have luminosities around , although they are usually variable. Their temperatures average about 2,300 K for the Mira S stars and 3,100 K for the non-Mira S stars, a few hundred K warmer than oxygen-rich AGB stars and a few hundred K cooler than carbon stars. Their radii average about for the Miras and for the non-miras, larger than oxygen-rich stars and smaller than carbon stars. Extrinsic S stars have luminosities typically around , temperatures between 3,150 and 4,000 K, and radii less than .
This means they lie below the red giant tip and will typically be RGB stars rather than AGB stars. Mass loss and dust Extrinsic S stars lose considerable mass through their stellar winds, similar to oxygen-rich TP-AGB stars and carbon stars. Typically the rates are around 1/10,000,000th those of the sun, although in extreme cases such as W Aquilae they can be more than ten times higher. It is expected that the existence of dust drives the mass loss in cool stars, but it is unclear what type of dust can form in the atmosphere of an S star with most carbon and oxygen locked into CO gas.
The stellar winds of S stars are comparable to oxygen-rich and carbon-rich stars with similar physical properties. There is about 300 times more gas than dust observed in the circumstellar material around S stars. It is believed to be made up of metallic iron, FeSi, silicon carbide, and forsterite. Without silicates and carbon, it is believed that nucleation is triggered by TiC, ZrC, and TiO2. Detached dust shells are seen around a number of carbon stars, but not S-type stars. Infrared excesses indicate that there is dust around most intrinsic S stars, but the outflow has not been sufficient and longlasting enough to form a visible detached shell.
The shells are thought to form during a superwind phase very late in the AGB evolution. Examples BD Camelopardalis is a naked-eye example of an extrinsic S star. It is slow irregular variable in a symbiotic binary system with a hotter companion which may also be variable. The mira variable Chi Cygni is an intrinsic S star. When near maximum light, it is the sky's brightest S-type star. It has a variable late type spectrum about S6 to S10, with features of zirconium, titanium and vanadium oxides, sometimes bordering on the intermediate MS type. A number of other prominent Mira variables such as R Andromedae and R Cygni are also S-type stars, as well as the peculiar semiregular variable π1 Gruis.
The naked-eye star ο1 Ori is an intermediate MS star and small amplitude semiregular variable with a DA3 white dwarf companion. The spectral type has been given as S3.5/1-, M3III(BaII), or M3.2IIIaS. References Category:Star types