cephalosporin: , cefuroxime and cefamandole) and third-generation ones (such as ceftazidime) tend to be more effective against gram-negative bacterial species that are resistant to the first-generation cephalosporins. Second-generation cephalosporins have proven effective against gonorrhea, Haemophilus influenzae, and the abscesses caused by Bacteroides

Ceglie Messapico, town, Puglia (Apulia) regione, southern Italy, northeast of Taranto. It is an agricultural-trading centre and has a medieval castle with cylindrical towers. In the surrounding area are numerous trulli (one-room houses built from local limestone, without the use of mortar, and

kapok, (Ceiba pentandra), gigantic tropical tree and the seed-hair fibers obtained from its fruit. Common throughout the tropics, the kapok is native to the New World and to Africa and was transported to Asia, where it is cultivated for its fiber, or floss. See also list of plant fibers. The

kapok: Physical description: The kapok is deciduous, dropping its foliage after seasonal rainy periods. Flowering occurs when the tree is leafless, thereby improving access for the bats that feed on the sugar-laden nectar of kapok blossoms. In doing so, the bats unwittingly pollinate the tree’s flowers. The flowers open…

silk floss tree, (Ceiba speciosa), thorny flowering tree of the mallow family (Malvaceae), native to South America but cultivated as an ornamental in other regions. The seeds yield a vegetable silk used in upholstery. It was formerly called Chorisia speciosa. The silk floss tree is a large

La Ceiba, city, northern Honduras. It lies along the Gulf of Honduras, in a lush, hot valley at the foot of 7,989-foot (2,435-metre) Mount Bonito. Developed in the late 19th century as a banana port, La Ceiba is one of the country’s major Caribbean ports. Besides bananas, the port handles

Ireland: Political and social organization: Greater landowners were supported by céilí, or clients. These and other grades of society, minutely classified and described by legal writers, tilled the soil and tended the cattle. Individual families were the real units of society and collectively exercised powers of ownership over their farms and territory. At law the…

Scotland: Daily life and social customs: …traditional local custom is the ceilidh (visit), a social occasion that includes music and storytelling. Once common throughout the country, the ceilidh is now a largely rural institution. Sports such as tossing the caber (a heavy pole) and the hammer throw are integral to the Highland games, a spectacle that…

ceiling, the overhead surface or surfaces covering a room, and the underside of a floor or a roof. Ceilings are often used to hide floor and roof construction. They have been favourite places for decoration from the earliest times: either by painting the flat surface, by emphasizing the structural

air-conditioning: …method of distribution is the ceiling diffuser, from which air is blown out along the ceiling level and allowed to settle down. The linear diffuser brings air through a plenum box or duct with a rectangular opening; louvers divert the down-flowing air. Other units are circular, and their fins radiate…

Howard Hawks: Films of the mid-1930s of Howard Hawks: Ceiling Zero (1936), an adaptation of a play by former pilot Frank Wead, was better. It starred Cagney as an indomitable airmail pilot and Pat O’Brien as his hard-boiled boss. Hawks’s next project, The Road to Glory (1936), was unrelated to his earlier film of…

ceilometer, device for measuring the height of cloud bases and overall cloud thickness. One important use of the ceilometer is to determine cloud ceilings at airports. The device works day or night by shining an intense beam of light (often produced by an infrared or ultraviolet transmitter or a

John Blackwell: …collected works were published as Ceinion Alun (1851).

John Ceiriog Hughes was a poet and folk musicologist who wrote outstanding Welsh-language lyrics. After working successively as a grocer’s helper, a clerk in Manchester, and a railway official in Wales, Hughes began winning poetry prizes in the 1850s and thereafter published several volumes of

Huw Morys was one of the finest Welsh poets of the 17th century. Morys wrote during the period when the strict bardic metres were in decline and the free metres of popular poetry were on the rise. He elevated this poetry to new dignity by skillful and sophisticated craftsmanship. Structurally

Ivan Klíma: …tmu, čekání na světlo (1993; Waiting for the Dark, Waiting for the Light), about a Czech cameraman floundering in the prosperity that follows oppression; and Ani svatí, ani andělé (2001; No Saints or Angels), about cultural and personal havoc in contemporary Prague. His biography of Čapek, The Life and Work…

La Skhira, seaport, eastern Tunisia. It is situated on the Gulf of Gabes, in Al-Sāḥil region. La Skhira is one of the six major seaports of Tunisia; it is specialized in handling Algerian and Tunisian petroleum exports. The port is also a pipeline terminal for Al-Dūlāb oil field, in western

Kosovo Liberation Army: Disbanding of the KLA and postwar issues: Others, such as Agim Çeku, a former KLA military head and a former prime minister (2006–08), as well Hashim Thaçi, a former KLA leader who became prime minister in 2008, were not indicted by the ICTY, although they are considered war criminals by Serbia.

motion-picture technology: Figural basis of animation: The development of cel (or cell) animation permitted the phased movements of the figures to be traced onto a succession of transparent celluloid sheets and superimposed, in turn, onto a single static drawing representing the background. With this technique the background could be drawn in somewhat greater detail…

Chelyabinsk, city and administrative centre, Chelyabinsk oblast (province), west-central Russia. It lies on the eastern flank of the Ural Mountains and on the Miass River. Chelyabinsk was founded as a fortress in 1736 on the site of a Bashkir village; it became a town in 1787. First a local centre

Chelyabinsk, oblast (province), west-central Russia. It is sited on the eastern flank of the Ural Mountains; a winding panhandle extends across to the western slopes. In the extreme east, the oblast extends onto the West Siberian Plain. The higher mountain areas are clothed in pine, fir, spruce,

Earth impact hazard: …than 1,500 people in the Chelyabinsk region of Russia were injured, mostly by flying glass which had been shattered by the shock wave of a meteorite 17 metres (56 feet) wide breaking up in the atmosphere. (The only verified case of a meteorite hitting and injuring a human being occurred…

Emmanuel Roblès: Dawn on Our Darkness), a novel set in Sardinia and concerning a man caught between love and duty. Le Vésuve (1961; Vesuvius) and Un Printemps d’Italie (1970; “A Springtime in Italy”) are love stories set in wartime Italy. His later novels include Venise en hiver…

Camilo José Cela was a Spanish writer who won the Nobel Prize for Literature in 1989. He is perhaps best known for his novel La familia de Pascual Duarte (1942; The Family of Pascual Duarte) and is considered to have given new life to Spanish literature. His literary production—primarily novels,

celadon, greenish ceramic glaze that is used on stoneware. Celadon is used both for the glaze itself and for the article so glazed. It is particularly valued in China, Korea, Thailand, and Japan. To create this ware, artisans apply a wash of slip (liquefied clay), which contains a high proportion

clay mineral: Mica mineral group: Celadonite and glauconite are ferric iron-rich species of dioctahedral micas. The ideal composition of celadonite may be expressed by K(Mg, Fe3+)(Si4 - xAlx)O10(OH)2, where x = 0–0.2. Glauconite is a dioctahedral mica species with tetrahedral Al substitution greater than 0.2 and octahedral Fe3+ or R3+

Celaenae, ancient fortress city of Phrygia (in present Turkey), the starting point of the march of the “Ten Thousand” under Cyrus (401 bc) against Artaxerxes (recounted in Xenophon’s Anabasis). In 333 Celaenae was conquered by Alexander the Great. The city was later renamed Apamea Cibotus (q.v.) by

Pleiades: Merope, Taygete, Celaeno, and Sterope, names now assigned to individual stars), daughters of Atlas and Pleione, were changed into the stars. The heliacal (near dawn) rising of the Pleiades in spring of the Northern Hemisphere has marked from ancient times the opening of seafaring and farming seasons,…

Pleiades: Electra, Taygete, Celaeno, Alcyone, Sterope, and Merope. They all had children by gods (except Merope, who married Sisyphus).

shrew rat: Natural history: … (genus Chrotomys) and the blazed Luzon shrew rat (Celaenomys silaceus) have a stripe running down the back. Fur is generally short, dense, and soft. Its texture is either velvety or woolly, although the prickly coat of the Sulawesi spiny rat (Echiothrix leucura) is a striking exception. The Sulawesi spiny rat…

Jelālī Revolts: …Tokat under the leadership of Celâl, a preacher of Shīʿite Islam. Major revolts later occurred in 1526–28, 1595–1610, 1654–55, and 1658–59.

Jelālī Revolts, rebellions in Anatolia against the Ottoman Empire in the 16th and 17th centuries. The first revolt occurred in 1519 near Tokat under the leadership of Celâl, a preacher of Shīʿite Islam. Major revolts later occurred in 1526–28, 1595–1610, 1654–55, and 1658–59. The major uprisings

Paul Celan was a Romanian-born poet who, though he never lived in Germany, gave the post-World War II literature of that country one of its most powerful and regenerative voices. His poetry was influenced stylistically by French Surrealism, and its subject matter by his grief as a Jew and a

celandine, any of several distinct flowering plants of similar appearance, mostly members of the poppy family (Papaveraceae). Several species are grown as garden wildflowers. The greater celandine (Chelidonium majus) is native to deciduous woods of Europe and Asia and is the only member of its

celandine: The celandine poppies, species of the genus Stylophorum, are native to North America and China. The plants resemble Chelidonium but have flowers twice the size and have two-paired much-divided leaves on the stem below the flower cluster and basal leaves. Celandine poppies have orange-yellow sap. Stylophorum…

Fucino Basin, former lake bed in L’Aquila province, Abruzzi region, central Italy, just east of Avezzano. The lake was once 37 mi (59 km) in circumference and about 100 ft (30 m) deep, although its level was subject to great variations because of the lack of an outlet. As early as ad 52 the emperor

Gracias: Celaque National Park, with the highest peak in Honduras, is nearby. Pop. (2001) 7,892; (2013) 12,697.

history of logic: Syllogisms: First figure: Barbara, Celarent, Darii, Ferio,

history of logic: Syllogisms: *Barbari, *Celaront.

Celastraceae, the staff-tree family, in the order Celastrales, comprising about 55 genera of woody vines, shrubs, and trees, native in tropical and temperate zones but best known for ornamental forms of the genera Euonymus and Celastrus (bittersweet). Fruit of the family is often colourful. Leaves

Celastrales, small order of flowering plants that includes 3 families, some 100 genera, and about 1,350 species. In the Angiosperm Phylogeny Group II (APG II) botanical classification system, Celastrales is placed in the Rosid I clade (see angiosperm). Celastraceae, or the bittersweet family,

bittersweet: The genus Celastrus, in the staff tree family (Celastraceae), includes the American bittersweet, or staff vine (C. scandens), and the Oriental bittersweet (C. orbiculatus), woody vines grown as ornamentals. The flowers, in whitish clusters, are followed by yellow to orange capsules, which split to reveal yellow to…

bittersweet: scandens), and the Oriental bittersweet (C. orbiculatus), woody vines grown as ornamentals. The flowers, in whitish clusters, are followed by yellow to orange capsules, which split to reveal yellow to crimson arils enclosing the seeds. Oriental bittersweet is a more vigorous climber, reaching up to 12 metres (40…

bittersweet: …tree family (Celastraceae), includes the American bittersweet, or staff vine (C. scandens), and the Oriental bittersweet (C. orbiculatus), woody vines grown as ornamentals. The flowers, in whitish clusters, are followed by yellow to orange capsules, which split to reveal yellow to crimson arils enclosing the seeds. Oriental bittersweet is a…

Italian literature: Fiction at the turn of the 21st century: …were Sebastiano Vassalli and especially Gianni Celati. Vassalli gradually distanced himself from the more radical experimentalism of Gruppo 63 so as to better exploit his gift for storytelling. La notte della cometa (1984; The Night of the Comet) is a fictionalized biography of the early 20th-century Orphic poet Dino Campana,…

Celaya, city, south-central Guanajuato estado (state), north-central Mexico. It lies on the north bank of the Laja River in the fertile Bajío region of the Mexican Plateau, 5,774 feet (1,760 meters) above sea level. Founded as Purísima Concepción de Celaya in 1571, the city played an important role

Battle of Celaya, (April 1915), decisive military engagement in the wars between revolutionary factions during the Mexican Revoluion of 1910–20. One of the largest and bloodiest battles in Mexican history, it was fought at Celaya, Guanajuato state, between the forces of Álvaro Obregón and Pancho

Spanish literature: Poetry: …to as a “Basque triumvirate”: Gabriel Celaya, a prewar Surrealist who became a leading spokesman for the opposition to Franco; Blas de Otero, an existentialist writing in the vein of Antonio Machado’s Campos de Castilla; and Ángela Figuera, a teacher, writer of children’s stories, feminist, and social activist, best known…

major industrial polymers: Polyacetal: Also called polyoxymethylene (POM) or simply acetal, polyacetal has the simplest structure of all the polyethers. It is manufactured in a solution process by anionic or cationic chain-growth polymerization of formaldehyde (H2C=O), a reaction analogous to vinyl polymerization. By itself, the polymer is unstable…

Niš: …the ruins of the Turkish-built Ćele Kula (Tower of Skulls) are embedded the skulls of more than 900 of the Serbs who fell at the Battle of Čegar. The Serbian army liberated Niš in 1877, and the town was ceded to them by the Treaty of Berlin (1878). In World…

Celebes, one of the four Greater Sunda Islands, Indonesia. A curiously shaped island with four distinct peninsulas that form three major gulfs—Tomini (the largest) on the northeast, Tolo on the east, and Bone on the south—Celebes has a coastline of 3,404 miles (5,478 km). Area including adjacent

crested black macaque, (Macaca nigra), a mainly arboreal Indonesian monkey named for the narrow crest of hair that runs along the top of the head from behind the overhanging brow. The crested black macaque is found only in the Minahasa region on the island of Sulawesi (Celebes) and on nearby Bacan

Celebes Sea, sea of the western Pacific Ocean, bordered on the north by the Sulu Archipelago and Sea and Mindanao island, on the east by the Sangihe Islands chain, on the south by Celebes (Sulawesi), and on the west by Borneo. It extends 420 miles (675 km) north-south by 520 miles (837 km)

Mehmed I was an Ottoman sultan who reunified the dismembered Ottoman territories following the defeat of Ankara (1402). He ruled in Anatolia and, after 1413, in the Balkans as well. Timur (Tamerlane), victorious over the Ottoman sultan Bayezid I at the Battle of Ankara, restored to the Turkmen

2015 marks the 45th annual celebration of Earth Day, observed on April 22 in the United States and elsewhere around the world. Earth Day is a time to acknowledge the achievements of the environmental movement and to raise awareness of ecological sustainability. spotlight, earth day, conservation,

The Celebrated Jumping Frog of Calaveras County, short story by Mark Twain, first published in a New York periodical, The Saturday Press in 1865. The narrator of the story, who is searching for a Reverend Leonidas Smiley, visits the long-winded Simon Wheeler, a miner, in hopes of learning his

May is officially designated Asian American and Pacific Islander Heritage Month in the United States, celebrating the accomplishments, contributions, and histories of Asian/Pacific Americans. Asian/Pacific Americans are broadly understood to have ethnic ties to countries in the Asian continent and

The month of June is nationally recognized as Caribbean American Heritage Month in the U.S. The year 2015 marks the 10th anniversary of the month-long celebration. National Caribbean American Heritage Month began in 2005 after the U.S House of Representatives passed a resolution acknowledging the

Elizabeth Cady was the daughter of a New York Supreme Court judge. Her father’s influence and her studies at a school that took the education of women seriously laid the foundation for her lifelong commitment to women’s suffrage. At age 25 she married Henry Brewster Stanton, a lawyer and

Millions of African Americans and other members of the African diaspora gather with family and friends each year from December 26 to January 1 to celebrate Kwanzaa. The secular holiday, which has its roots in African harvest festivals, is an affirmation of African family and social values. Kwanzaa

August 27, 2025, marks the 60th anniversary of the drowning death of Le Corbusier, one of the iconic architects of the 20th century. His travels as a young man helped him develop the principles he followed as an architect—and wrote extensively about—over the course of his life. Largely self-taught,

Throughout the month of June, communities in the U.S. and many other nations hold events celebrating lesbian, gay, bisexual, and transgender identities, often collectively known as Gay Pride or LGBTQ Pride. Gay Pride celebrations are usually a series of events culminating in a parade of colorful

The Islamic holy month of Ramadan is a time for Muslims all over the world to renew their focus on spiritual life and its practical application in daily life. It is the ninth month of the Muslim calendar. According to Islamic tradition, it was on the 27th day of Ramadan that the Prophet Muhammad

Bob Marley became a musical legend who instilled the poor of his country with a sense of identity. spotlight, bob marley, music, musician, birthday, jamaica,

Albert Einstein’s profound array of achievements has made the word "Einstein" synonymous with genius. spotlight, albert einstein, science, history, inventors, scientists,

Led Zeppelin: Legacy: …Grammy Award in 2014 for Celebration Day (2012), a live album derived from the 2007 reunion show. In 2012 Led Zeppelin was named a Kennedy Center honoree.

Olivia Newton-John: Career: …was released in 2002, and A Celebration in Song (2008) contain duets with musicians such as New Zealand–born Australian country singer Keith Urban and American pop-rock singer Richard Marx. The albums Stronger than Before (2005) and Grace and Gratitude (2006) include inspirational and meditative songs. LIV ON (2016) deals with…

Friedrich Hölderlin: …period 1802–06, including “Friedensfeier” (“Celebration of Peace”), “Der Einzige” (“The Only One”), and “Patmos,” products of a mind on the verge of madness, are apocalyptic visions of unique grandeur. He also completed verse translations of Sophocles’ Antigone and Oedipus Tyrannus, published in 1804. In this year a devoted friend,…

2026 Milano Cortina Olympics: Athletes to Watch: Macklin Celebrini: Macklin Celebrini is an up-and-coming ice hockey player who made his Olympic debut in 2026 playing for the Canadian national team. He was just 17 years old when he entered Boston University in the fall of 2023. Following a standout season, he became the youngest-ever…

Woody Allen: The 1990s and sexual-abuse allegations: Celebrity (1998) followed. Shot in black-and-white by Nykvist—with a cast that included Kenneth Branagh, Leonardo DiCaprio, Winona Ryder, and Charlize Theron—the film was considered a minor entry in Allen’s oeuvre. In the more-focused Sweet and Lowdown (1999) Sean Penn turned in a memorable

parasocial interaction: …parasocial relationship with the same celebrity without feeling jealous of one another; in fact, in many cases, sharing their dedication to a mass media persona brings people closer together.

Rod Blagojevich: Corruption, conviction, and pardon: He also appeared on The Celebrity Apprentice, hosted by Trump; Patti Blagojevich, his wife, appeared on NBC reality show I’m a Celebrity…Get Me Out of Here. A federal judge had barred Rod Blagojevich from participating in I’m a Celebrity as it required international travel. Blagojevich’s trial began in June…

Courtney Love: In 1998 Hole released Celebrity Skin, a commercial and critical success, but the group disbanded in May 2002.

Southeast Asian arts: Java: …xylophone (gambang), the zither (celempung) with 26 strings tuned in pairs, an end-blown flute (suling), and a 2-stringed lute (called a rebab by the Javanese), which leads the orchestra. In loud-sounding music, the soft-sounding instruments are not played, and the drum (kendang) leads the orchestra. The third group provides…

Quintus Caecilius Metellus Celer was a leading Roman politician of the late 60s bc who became an opponent of Pompey the Great, the Catilinarian conspiracy (see Catiline), and the formation of the secret political agreement of Julius Caesar, Pompey, and Marcus Crassus. Adopted from one branch of the

Francis Collins: …questioned when a rival operation, Celera Genomics, emerged in 1998 and appeared to be working even faster than the HGP at deciphering the human deoxyribonucleic acid (DNA) sequence. Headed by American geneticist and businessman J. Craig Venter, a former NIH scientist, Celera had devised its own, quicker method—though some scientists,…

celeriac, (subspecies Apium graveolens, variety rapaceum), type of celery (Apium graveolens, variety rapaceum) grown for its knobby edible hypocotyl (stem), which is used as a raw or cooked vegetable. Originally cultivated in the Mediterranean and in northern Europe, it was introduced into Britain

celery, (Apium graveolens), herbaceous plant of the parsley family (Apiaceae). Celery is usually eaten cooked as a vegetable or as a delicate flavoring in a variety of stocks, casseroles, and soups. In the United States raw celery is also served by itself or with spreads or dips as an appetizer and

napa cabbage, (Brassica rapa, variety pekinensis), form of Chinese cabbage, belonging to the mustard family (Brassicaceae), cultivated for its edible leaves. Napa cabbage is widely grown in eastern Asia and is commonly used to make kimchi, a traditional Korean dish made of spicy fermented

Podocarpaceae: In the genus Phyllocladus, the foliar leaves are replaced by flattened branchlets (phylloclades) resembling leaves. The staminate, or pollen-bearing, cones are borne in a terminal or axillary position on leafy twigs; the ovulate, or seed-bearing, cones at maturity become fleshy and sometimes brightly coloured and surmount the fleshy…

celeriac, (subspecies Apium graveolens, variety rapaceum), type of celery (Apium graveolens, variety rapaceum) grown for its knobby edible hypocotyl (stem), which is used as a raw or cooked vegetable. Originally cultivated in the Mediterranean and in northern Europe, it was introduced into Britain

celery: …tiny seedlike fruits, known as celery seed, resemble the plant itself in taste and aroma and are used as a seasoning, particularly in soups and pickles.

smallage, (Apium graveolens), wild celery; strongly scented, erect, biennial herb of the carrot family (Apiaceae, or Umbelliferae) widely distributed in moist places within the temperate zones, and grown for use as a flavouring similar to celery. In traditional medicine, smallage roots are used as

celery-top pine, (Phyllocladus aspleniifolius), slow-growing ornamental and timber conifer (family Podocarpaceae), native to temperate rainforests of Tasmania at elevations from sea level to 750 metres (2,500 feet). The dense golden-brown wood is used in fine furniture. The tree is shrubby at high

celesta, orchestral percussion instrument resembling a small upright piano, patented by a Parisian, Auguste Mustel, in 1886. It consists of a series of small metal bars (and hence is a metallophone) with a keyboard and a simplified piano action in which small felt hammers strike the bars. Each bar

celesta, orchestral percussion instrument resembling a small upright piano, patented by a Parisian, Auguste Mustel, in 1886. It consists of a series of small metal bars (and hence is a metallophone) with a keyboard and a simplified piano action in which small felt hammers strike the bars. Each bar

Rashida Jones: Producing and writing work: They wrote the 2012 film Celeste and Jesse Forever, which starred Jones alongside Andy Samberg. Jones and McCormack also worked on the screenplay for the 2019 film Toy Story 4 but wound up leaving the Pixar project. “We parted ways because of creative and, more importantly, philosophical differences,” they told…

Michael Bennet: Richard Celeste, he went to Yale Law School, where he served as editor of The Yale Law Journal before graduating in 1993. Bennet then worked as a clerk for the Fourth Circuit Court of Appeals and later served as counsel (1995–97) to the U.S. deputy…

celestial coordinates, Set of numbers used to pinpoint the position in the sky (see celestial sphere) of a celestial object. Coordinate systems used include the horizon system (altitude and azimuth), galactic coordinates, the ecliptic system (measured relative to the orbital plane of Earth), and

celestial coordinates, Set of numbers used to pinpoint the position in the sky (see celestial sphere) of a celestial object. Coordinate systems used include the horizon system (altitude and azimuth), galactic coordinates, the ecliptic system (measured relative to the orbital plane of Earth), and

long: …dragons: the Celestial Dragon (Tianlong), who guards the heavenly dwellings of the gods; the Dragon of Hidden Treasure (Fuzanglong); the Earth Dragon (Dilong), who controls the waterways; and the Spiritual Dragon (Shenlong), who controls the rain and winds. In popular belief only the latter two were significant; they were…

Equator: celestial equator is the great circle in which the plane of the terrestrial Equator intersects the celestial sphere; it consequently is equidistant from the celestial poles. When the Sun lies in its plane, day and night are everywhere of equal length, a twice-per-year occurrence (about…

celestial globe, representation of stars and constellations as they are located on the apparent sphere of the sky. Celestial globes are used for some astronomical or astrological calculations or as ornaments. Some globes were made in ancient Greece; Thales of Miletus (fl. 6th century bce) is

Hungarian literature: Writing after 1945: …internationally for Harmonia Caelestis (2000; Celestial Harmonies), which chronicles some seven centuries of his own distinguished family’s history. Esterházy’s Semmi művészet (2008; Not Art: A Novel) depicts a football- (soccer-) obsessed mother’s relationship with her son.

astronomical map: The ecliptic system: Celestial longitude and latitude are defined with respect to the ecliptic and ecliptic poles. Celestial longitude is measured eastward from the ascending intersection of the ecliptic with the equator, a position known as the “first point of Aries,” and the place of the Sun at the time of…

astronomical map: The ecliptic system: Celestial longitude is measured eastward from the ascending intersection of the ecliptic with the equator, a position known as the “first point of Aries,” and the place of the Sun at the time of the vernal equinox about March 21. The first point of Aries…

Tianshidao, great popular Daoist movement that occurred near the end of China’s Han dynasty (206 bce–220 ce) and greatly weakened the government. The Tianshidao movement became a prototype of the religiously inspired popular rebellions that were to erupt periodically throughout China for the next

celestial mechanics, in the broadest sense, the application of classical mechanics to the motion of celestial bodies acted on by any of several types of forces. By far the most important force experienced by these bodies, and much of the time the only important force, is that of their mutual

Pierre-Simon, marquis de Laplace: …Traité de mécanique céleste (Celestial Mechanics), appearing in five volumes between 1798 and 1827, summarized the results obtained by his mathematical development and application of the law of gravitation. He offered a complete mechanical interpretation of the solar system by devising methods for calculating the motions of the planets…

telescope: Astronomical transit instruments: The observer’s meridian is a great circle on the celestial sphere that passes through the north and south points of the horizon as well as through the zenith of the observer. Restricting the telescope to motion only in the meridian provides an added degree of stability, but…