النجمة أو النجم هو عبارة عن جسم فلكي كروي من البلازما ضخم ولامع ومتماسك بفعل الجاذبية.
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النجمة أو النجم هو عبارة عن جسم فلكي كروي من البلازما ضخم ولامع ومتماسك بفعل الجاذبية.
1. نجم – A star is a luminous sphere of plasma held together by its own gravity. The nearest star to Earth is the Sun, many other stars are visible to the naked eye from Earth during the night, appearing as a multitude of fixed luminous points in the sky due to their immense distance from Earth. Historically, the most prominent stars were grouped into constellations and asterisms, astronomers have assembled star catalogues that identify the known stars and provide standardized stellar designations. However, most of the stars in the Universe, including all stars outside our galaxy, indeed, most are invisible from Earth even through the most powerful telescopes. Almost all naturally occurring elements heavier than helium are created by stellar nucleosynthesis during the stars lifetime, near the end of its life, a star can also contain degenerate matter. Astronomers can determine the mass, age, metallicity, and many properties of a star by observing its motion through space, its luminosity. The total mass of a star is the factor that determines its evolution. Other characteristics of a star, including diameter and temperature, change over its life, while the environment affects its rotation. A plot of the temperature of stars against their luminosities produces a plot known as a Hertzsprung–Russell diagram. Plotting a particular star on that allows the age and evolutionary state of that star to be determined. A stars life begins with the collapse of a gaseous nebula of material composed primarily of hydrogen, along with helium. When the stellar core is sufficiently dense, hydrogen becomes steadily converted into helium through nuclear fusion, the remainder of the stars interior carries energy away from the core through a combination of radiative and convective heat transfer processes. The stars internal pressure prevents it from collapsing further under its own gravity, a star with mass greater than 0.4 times the Suns will expand to become a red giant when the hydrogen fuel in its core is exhausted. In some cases, it will fuse heavier elements at the core or in shells around the core, as the star expands it throws a part of its mass, enriched with those heavier elements, into the interstellar environment, to be recycled later as new stars. Meanwhile, the core becomes a remnant, a white dwarf. Binary and multi-star systems consist of two or more stars that are bound and generally move around each other in stable orbits. When two such stars have a close orbit, their gravitational interaction can have a significant impact on their evolution. Stars can form part of a much larger gravitationally bound structure, historically, stars have been important to civilizations throughout the world
2. نجمة (مضلع) – In geometry, a star polygon is a type of non-convex polygon. Only the regular polygons have been studied in any depth. The first usage is included in polygrams which includes polygons like the pentagram, star polygon names combine a numeral prefix, such as penta-, with the Greek suffix -gram. The prefix is normally a Greek cardinal, but synonyms using other prefixes exist, for example, a nine-pointed polygon or enneagram is also known as a nonagram, using the ordinal nona from Latin. The -gram suffix derives from γραμμή meaning a line, alternatively for integers p and q, it can be considered as being constructed by connecting every qth point out of p points regularly spaced in a circular placement. A regular star polygon is denoted by its Schläfli symbol, where p and q are relatively prime, the symmetry group of is dihedral group Dn of order 2n, independent of k. A regular star polygon can also be obtained as a sequence of stellations of a regular core polygon. Regular star polygons were first studied systematically by Thomas Bradwardine, if p and q are not coprime, a degenerate polygon will result with coinciding vertices and edges. For example will appear as a triangle, but can be labeled with two sets of vertices 1-6 and this should be seen not as two overlapping triangles, but a double-winding of a single unicursal hexagon. For |n/d|, the vertices have an exterior angle, β. These polygons are often seen in tiling patterns, the parametric angle α can be chosen to match internal angles of neighboring polygons in a tessellation pattern. The interior of a polygon may be treated in different ways. Three such treatments are illustrated for a pentagram, branko Grunbaum and Geoffrey Shephard consider two of them, as regular star polygons and concave isogonal 2n-gons. These include, Where a side occurs, one side is treated as outside and this is shown in the left hand illustration and commonly occurs in computer vector graphics rendering. The number of times that the polygonal curve winds around a given region determines its density, the exterior is given a density of 0, and any region of density >0 is treated as internal. This is shown in the illustration and commonly occurs in the mathematical treatment of polyhedra. Where a line may be drawn between two sides, the region in which the line lies is treated as inside the figure and this is shown in the right hand illustration and commonly occurs when making a physical model. When the area of the polygon is calculated, each of these approaches yields a different answer, star polygons feature prominently in art and culture
3. كاتب ياسين – Kateb Yacine (Arabic pronunciation, was an Algerian writer notable for his novels and plays, both in French and Algerian Arabic dialect, and his advocacy of the Berber cause. Kateb Yacine was officially born on August 6,1929 in Constantine, although his birth name is Yacine Kateb, he once said that he was so used to hearing his teachers calling out names with the last name first that he adopted Kateb Yacine as a pen name. He was born into a scholarly maraboutic Berber family from Sedrata in western Souk Ahras and his maternal grandfather was the bach adel, or deputy judge of the qadi in Condé Smendou. His father was a lawyer, and the family followed him through his various assignments in different parts of the country, young Kateb, attended the Sedrata Quran school in 1937, then in 1938 the French school in Lafayette in Little Kabylie, where the family had moved. In 1941 he enrolled in the colonial collège of Setif as a boarder, Kateb Yacine was in his third year of collège when the demonstrations of May 8,1945 occurred. He participated in demonstrations that ended with the massacre of between six and eight thousand Algerians by the French army and police in the Sétif and Guelma massacre. Three days later he was placed under arrest and imprisoned for two months, from that point on he became a partisan for the nationalist cause. There he met Nedjma, an already married cousin with whom he lived for eight months. While living with Nedjma he published his first collection of poetry in 1946 and he had already become politicized and started giving lectures under the auspices of the Algerian Peoples Party, the great nationalist party of the masses. Yacine went to Paris in 1947, into the den as he put it. In May 1947 he joined the Algerian Communist Party and gave a lecture in the Salle des Sociétés savantes on emir Abd al-Qadir, during a second visit to France the following year he published Nedjma ou le Poème du Couteau in the revue Le Mercure de France. He was a journalist at the daily Alger Républicain between 1949 and 1951, his first great reports coming from Saudi Arabia and Sudan, after his fathers death in 1950 Yacine worked as a longshoreman in Algiers. He returned to Paris where he would stay until 1959, during this period in Paris he worked with Malek Haddad, developed a relationship with Mhamed Issiakhem, and in 1954, spoke extensively with Bertold Brecht. In 1954, the revue Esprit published Yacines play Le cadavre encerclé, during the Algerian War of Independence, Yacine was forced to travel abroad for a long time due to the harassment he faced from the DST. He lived in places, subsisting as a guest writer or working various odd jobs in France, Belgium, Germany, Italy, Yugoslavia. After a stay in Cairo, Yacine returned again to Algeria in 1962 and he resumed writing for Alger Républicain but traveled frequently between 1963 and 1967 to Moscow, France and Germany. La Femme sauvage, which he had written between 1954 and 1959, was performed in Paris in 1963, les Ancêtres redoublent de férocité was staged in 1967. La Poudre dintelligence was also staged in Paris in 1967 and an Algerian Arabic version in Algiers in 1969, the same year Yacine returned to make a more permanent home in Algeria
4. مشاهير – Celebrity status is often associated with wealth, while fame often provides opportunities to make money. Successful careers in sports and entertainment are commonly associated with celebrity status, People may also become celebrities due to media attention on their lifestyle, wealth, or controversial actions, or for their connection to a famous person. Throughout recorded history there are accounts of people who attracted the trappings of celebrity which would be recognized today, athletes in Ancient Greece were welcomed home as heroes, had songs and poems written in their honor, and received free food and gifts from those seeking celebrity endorsement. Ancient Rome similarly lauded actors and notorious gladiators, and Julius Caesar appeared on a coin in his own lifetime, in the 12th century, Thomas Becket became famous following his murder. He was promoted by the Christian Church as a martyr and images of him, the cult of personality can be traced back to the Romantics in the 18th Century, whose livelihood as artists and poets depended on the currency of their reputation. The establishment of cultural hot-spots became an important factor in the process of generating fame, for example, London, newspapers started including gossip columns and certain clubs and events became places to be seen in order to receive publicity. The movie industry spread around the globe in the first half of the 20th Century, yet, celebrity wasnt always tied to actors in films, especially when cinema was starting out as a medium. The second half of the century saw television and popular music bring new forms of celebrity, such as the rock star, unlike movies, television created celebrities who were not primarily actors, for example, presenters, talk show hosts and news readers. In the sixties and early seventies the book publishing industry began to persuade major celebrities to put their names on autobiographies and other titles in a genre called celebrity publishing. In most cases the book was not written by the celebrity but by a ghost-writer, cultures and regions with a significant population may have their own independent celebrity systems, with distinct hierarchies. For example, the Canadian province of Quebec, which is French-speaking, has its own system of French-speaking television, movie, a person who garners a degree of fame in one culture may be considered less famous or obscure in another. S. Whereas the francophone Canadian singer Celine Dion is well known in both the French-speaking world and in the United States, regions within a country, or cultural communities can also have their own celebrity systems, especially in linguistically or culturally distinct regions such as Quebec or Wales. Regional radio personalities, newscasters, politicians or community leaders may be local or regional celebrities and these informal rankings indicate a placing within a hierarchy. However, due to differing levels of celebrity in different regions, a Brazilian actor might be a B-list action film actor in the U. S. but an A-list star in Portugal. Some elements are associated with fame, such as appearing on the cover of Time, being spoofed in Mad, having a wax statue in Madame Tussauds, certain people are known even to people unfamiliar with the area in which they excelled. If one has to name a famous boxer, they are likely to name Muhammad Ali or Mike Tyson. The same phenomenon is true for fictional characters, superman, Spider-Man, The Hulk, Wonder Woman and Batman represent super heroes to a far wider audience than that of the comics and graphic novels in which they appear. Disney have themeparks around the world rely on the fame of its creations headed by Mickey Mouse
5. نجم (نبات) – Aster is a genus of flowering plants in the family Asteraceae. After this split there are roughly 180 species within the genus, all, the name Aster comes from the Ancient Greek word ἀστήρ, meaning star, referring to the shape of the flower head. Many species and a variety of hybrids and varieties are popular as garden plants because of their attractive, Aster species are used as food plants by the larvae of a number of Lepidoptera species—see list of Lepidoptera that feed on Aster. Asters can grow in all hardiness zones, the genus Aster is now generally restricted to the Old World species, with Aster amellus being the type species of the genus, as well as of the family Asteraceae. Regardless of the change, all are still widely referred to as asters, or Michaelmas daisies, because of their typical blooming period. See the List of Aster synonyms for more information, in the United Kingdom, there are only two native members of the genus, goldilocks, which is very rare, and Aster tripolium, the sea aster. Aster alpinus spp. vierhapperi is the species native to North America. Ontario Wildflowers website Lots of info about Asters Pictures of Aster flowers thriving in the autumn sunshine