1.
Azophi (crater)
–
Azophi is a lunar impact crater that lies in the rugged south-central highlands of the Moon. The northwest rim is attached to the smaller crater Abenezra. To the east-southeast is the large and irregular Sacrobosco, the wide outer rim of Azophi has a somewhat polygonal shape with rounded corners. The edge is sharp and cleft-like. The rim is not significantly worn or impacted by smaller craters, with the exception of Azophi C, the interior floor lacks a central peak and is only marked by a few tiny craterlets. It is named after the 10th-century Persian astronomer Abd Al-Rahman Al Sufi, also known by his western name, by convention these features are identified on lunar maps by placing the letter on the side of the crater midpoint that is closest to Azophi. 12621 Alsufi, asteroid named after Al Sufi
2.
Rey, Iran
–
Rey or Ray, also known as Rhages and formerly as Arsacia, is the capital of Rey County in Tehran Province of Iran, and the oldest existing city in the province. Ray today has been absorbed into the Greater Tehran metropolitan area, Ray is connected via the Tehran Metro to the rest of Tehran and has many industries and factories in operation. Note on spelling, According to the Iranian Chamber Society, the spelling of the city in both English and Persian is Ray, though variations in spelling also exist. The city university also uses the spelling Ray, as does the Encyclopædia Iranica published by Columbia University, a settlement began here c 6,000 BCE as part of the Central Plateau Culture. The settlement was used as a capital by the Arsacids called Rhaga, in Classical Greco-Roman geography it was called Rhagae. It is mentioned several times in the Apocrypha and its name dates back to the pre-Median period. Some historians attribute its building to ancient mythological monarchs, and some believe that Ray was the seat of a dynasty of Zoroastrian leader. During the Seleucid period, Alexander the Greats general Seleucus I Nicator renamed the city as Europos, Rey is also shown on the 4th century Peutinger Map. It has been home to pillars of science like Rhazes, Rey was one of the capital cities of the Seljuq Empire in the 11th century. In the 13th century after the Mongol conquest the town was severely damaged, there is also a shrine there, dedicated to commemorate Princess Shahr Banu, eldest daughter of the last ruler of the Sassanid Empire. She gave birth to Ali Zayn al Abidin, the fourth holy Imam of the Shia faith and this was through her marriage to Husayn ibn Ali, the grandson of Muhammad, the prophet of Islam. A nearby mountain is named after her. In the middle of the 19th century Ray was described as place of ruins, being the only important pilgrimage site in vicinity to the royal court in the new capital Tehran brought more people to visit the shrine and a major restoration was sponsored by the court. Thus Ray was the first place in Iran to be connected to the capital by a railroad in 1888, the shrine contains the tomb of ‘Abdul ‘Adhīm ibn ‘Abdillāh al-Hasanī, a fifth generation descendant of Hasan ibn ‘Alī and a companion of Muhammad al-Taqī. He was entombed here after his death in the 9th century, some of the discovered objects are displayed at museums in Iran, Chicago, and Philadelphia. The hill, which is now leveled out and most artifacts unrecoverable due to real estate expansion in the 1980s and 1990s, was the home of Aryans about 6,000 years ago. Since Ray was used as a center due to its beautiful attractions under the reign of the Qajar dynasty. In 1831 his portrait and that of some Qajar princes were engraved on a rock at Cheshmeh Ali hill, Tuğrul Tower, constructed under the Seljuqs at the order of Tuğrul Beg in 1140, once he transferred the capital city from Nishapur to Ray
3.
Buyid dynasty
–
The Buyid dynasty or the Buyids, also known as Buwaihids, Bowayhids, Buyahids, or Buyyids, was an Iranian Shia dynasty of Daylamite origin. As Daylamite Iranians the Buyids consciously revived symbols and practices of Persias Sassānid dynasty, in fact, beginning with Adud al-Dawla they used the ancient Sassānid title Shāhanshāh, literally king of kings. At its greatest extent, the Buyid dynasty encompassed most of todays Iran, Iraq, Kuwait, and Syria, along parts of Oman. The word Būya is a Middle Persian name ending in the diminutive ـویه, the Buyids were descendants of Panah-Khusrau, a Zoroastrian from Daylam. He had a son named Buya, who was a fisherman from Lahijan, Buya later had three sons named Ahmad, Ali, and Hasan, who would later carve the Buyid kingdom together. Most historians agree that the Buyids were Daylamites, the Buyids claimed royal lineage from Bahram V, 15th king of the Sasanian Empire. Ali was later joined by his two brothers, Hasan ibn Buya and Ahmad ibn Buya. In 932, Ali was given Karaj as his fief, however, Alis independent actions made Mardavij plan to have him killed, but fortunately for Ali, he was informed of Mardavijs plan by the latters own vizier. The Buyids brother, with 400 of their Daylamite supporters, then fled to Fars, however, the Buyids and the Abbasid general Yaqut shortly came into a struggle for the control of Fars, which the Buyids eventually emerged victorious in. This victory opened the way for the conquest of the capital of Fars, Ali also made an alliance with the landowners of Fars, which included the Fasanjas family, which would later produce many prominent statesmen for the Buyids. Furthermore, Ali also to enlist more soldiers, which included the Turks, Ali then sent his brother Ahmad on an expedition to Kirman, but was forced to withdraw from them after opposition from the Baloch people and the Qafs. In addition to the territories the Buyids had conquered, Kirman was conquered in 967, Oman, the Jazira, Tabaristan. After this, however, the Buyids went into a decline, with pieces of the confederation gradually breaking off. When he made the death of his public, he was given the title of Samsam al-Dawla. However, Aduds other son, Shirdil Abul-Fawaris, challenged the authority of Samsam al-Dawla, meanwhile, a Marwanid chieftain named Badh, seized Diyabakr and forced Samsam al-Dawla to recognize him as the vassal ruler of the region. During the same period, Samsam al-Dawla also managed to seize Basra and Khuzistan, during the mid-11th century, the Buyid amirates gradually fell to the Ghaznavid and Seljuq Turks. In 1029, Majd al-Dawla, who was facing an uprising by his Dailami troops in Ray, when Sultan Mahmud arrived, he deposed Majd al-Dawla, replaced him with a Ghaznavid governor and ended the Buyid dynasty in Ray. In 1055, Tughrul conquered Baghdad, the seat of the caliphate, like the Buyids, the Seljuqs kept the Abbasid caliphate as the titular ruler
4.
Shiraz
–
Shiraz is the sixth-most-populous city of Iran and the capital of Fars Province. At the 2011 census, the population of the city was 1,700,665, Shiraz is located in the southwest of Iran on the Roodkhaneye Khoshk seasonal river. It has a climate and has been a regional trade center for over a thousand years. Shiraz is one of the oldest cities of ancient Persia, the earliest reference to the city, as Tiraziš, is on Elamite clay tablets dated to 2000 BC. In the 13th century, Shiraz became a center of the arts and letters, due to the encouragement of its ruler. It was the capital of Persia during the Zand dynasty from 1750 until 1800, two famous poets of Iran, Hafez and Saadi, are from Shiraz, whose tombs are on the north side of the current city boundaries. Shiraz is known as the city of poets, literature, wine and it is also considered by many Iranians to be the city of gardens, due to the many gardens and fruit trees that can be seen in the city, for example Eram Garden. Shiraz has had major Jewish and Christian communities, the crafts of Shiraz consist of inlaid mosaic work of triangular design, silver-ware, pile carpet-weaving and weaving of kilim, called gilim and jajim in the villages and among the tribes. In Shiraz industries such as cement production, sugar, fertilizers, textile products, wood products, metalwork, Shirāz also has a major oil refinery and is also a major center for Irans electronic industries, 53% of Irans electronic investment has been centered in Shiraz. Shiraz is home to Irans first solar power plant, recently the citys first wind turbine has been installed above Babakoohi mountain near the city. The earliest reference to the city is on Elamite clay tablets dated to 2000 BCE, found in June 1970, the tablets written in ancient Elamite name a city called Tiraziš. Phonetically, this is interpreted as /tiračis/ or /ćiračis/ and this name became Old Persian /širājiš/, through regular sound change comes the modern Persian name Shirāz. The name Shiraz also appears on clay sealings found at a 2nd-century CE Sassanid ruin, by some of the native writers, the name Shiraz has derived from a son of Tahmuras, the third Shāh of the world according to Ferdowsis Shāhnāma. Shiraz is most likely more than 4,000 years old, the name Shiraz is mentioned in cuneiform inscriptions from around 2000 BC found in southwestern corner of the city. According to some Iranian mythological traditions, it was erected by Tahmuras Diveband. The oldest sample of wine in the world, dating to approximately 7,000 years ago, was discovered on clay jars recovered outside of Shiraz, in the Achaemenian era, Shiraz was on the way from Susa to Persepolis and Pasargadae. In Ferdowsis Shāhnāma it has said that Artabanus V, the Parthian Emperor of Iran. Ghasre Abu-Nasr which is originally from Parthian era is situated in this area, during the Sassanid era, Shiraz was in between the way which was connecting Bishapur and Gur to Istakhr
5.
Isfahan
–
Isfahan, historically also rendered in English as Ispahan, Sepahan, Esfahan or Hispahan, is the capital of Isfahan Province in Iran, located about 340 kilometres south of Tehran. The Greater Isfahan Region had a population of 3,793,104 in the 2011 Census, the counties of Isfahan, Borkhar, Najafabad, Khomeynishahr, Shahinshahr, Mobarakeh, Falavarjan, Tiran o Karvan, Lenjan and Jay all constitute the metropolitan city of Isfahan. Isfahan is located on the main north–south and east–west routes crossing Iran and it flourished from 1050 to 1722, particularly in the 16th and 17th centuries under the Safavid dynasty, when it became the capital of Persia for the second time in its history. Even today, the city retains much of its past glory and it is famous for its Persian–Islamic architecture, with many beautiful boulevards, covered bridges, palaces, mosques, and minarets. This led to the Persian proverb Esfahān nesf-e- jahān ast, the Naghsh-e Jahan Square in Isfahan is one of the largest city squares in the world. It has been designated by UNESCO as a World Heritage Site, the city also has a wide variety of historic monuments and is known for the paintings, history and architecture. Isfahan City Center is also the 5th largest shopping mall in the world, see also, Names of Isfahan The name of the region derives from Middle Persian Spahān. Spahān is attested in various Middle Persian seals and inscriptions, including that of Zoroastrian Magi Kartir, the present-day name is the Arabicized form of Ispahan. The region appears with the abbreviation GD on Sasanian numismatics, in Ptolemys Geographia it appears as Aspadana, translating to place of gathering for the army. It is believed that Spahān derives from spādānām the armies, Old Persian plural of spāda, the history of Isfahan can be traced back to the Palaeolithic period. In recent discoveries, archaeologists have found artifacts dating back to the Palaeolithic, Mesolithic, Neolithic, Bronze and Iron ages. It is said that after Cyrus the Great freed the Jews from Babylon some Jews returned to Jerusalem whereas some others decided to live in Persia, but, actually this happened later in the Sasanid period when a Jewish colony was made in the vicinity of the Sasanid. They did not settle anywhere or in any city without examining the water. They did all along until they reached the city of Isfahan, there they rested, examined the water and soil and found that both resembled Jerusalem. Upon they settled there, cultivated the soil, raised children and grandchildren, under the Parthians, Arsacid governors administered a large province from Isfahan, and the citys urban development accelerated to accommodate the needs of a capital city. The next empire to rule Persia, the Sassanids, presided over changes in their realm, instituting sweeping agricultural reform and reviving Iranian culture. The city was called by the name and the region by the name Aspahan or Spahan. The city was governed by Espoohrans or the members of seven noble Iranian families who had important royal positions, extant foundations of some Sassanid-era bridges in Isfahan suggest that the kings were also fond of ambitious urban planning projects
6.
Astronomer
–
An astronomer is a scientist in the field of astronomy who concentrates their studies on a specific question or field outside of the scope of Earth. They look at stars, planets, moons, comets and galaxies, as well as other celestial objects — either in observational astronomy. Examples of topics or fields astronomers work on include, planetary science, solar astronomy, there are also related but distinct subjects like physical cosmology which studies the Universe as a whole. Astronomers usually fit into two types, Observational astronomers make direct observations of planets, stars and galaxies, and analyze the data, theoretical astronomers create and investigate models of things that cannot be observed. They use this data to create models or simulations to theorize how different celestial bodies work, there are further subcategories inside these two main branches of astronomy such as planetary astronomy, galactic astronomy or physical cosmology. Today, that distinction has disappeared and the terms astronomer. Professional astronomers are highly educated individuals who typically have a Ph. D. in physics or astronomy and are employed by research institutions or universities. They spend the majority of their time working on research, although quite often have other duties such as teaching, building instruments. The number of astronomers in the United States is actually quite small. The American Astronomical Society, which is the organization of professional astronomers in North America, has approximately 7,000 members. This number includes scientists from other such as physics, geology. The International Astronomical Union comprises almost 10,145 members from 70 different countries who are involved in research at the Ph. D. level. Before CCDs, photographic plates were a method of observation. Modern astronomers spend relatively little time at telescopes usually just a few weeks per year, analysis of observed phenomena, along with making predictions as to the causes of what they observe, takes the majority of observational astronomers time. Astronomers who serve as faculty spend much of their time teaching undergraduate and graduate classes, most universities also have outreach programs including public telescope time and sometimes planetariums as a public service to encourage interest in the field. Those who become astronomers usually have a background in maths, sciences. Taking courses that teach how to research, write and present papers are also invaluable, in college/university most astronomers get a Ph. D. in astronomy or physics. Keeping in mind how few there are it is understood that graduate schools in this field are very competitive
7.
Islamic Golden Age
–
This period is traditionally said to have ended with the collapse of the Abbasid caliphate due to Mongol invasions and the Sack of Baghdad in 1258 AD. A few contemporary scholars place the end of the Islamic Golden Age as late as the end of 15th to 16th centuries, the metaphor of a golden age began to be applied in 19th-century literature about Islamic history, in the context of the western aesthetic fashion known as Orientalism. There is no definition of term, and depending on whether it is used with a focus on cultural or on military achievement. During the early 20th century, the term was used only occasionally, the Muslim government heavily patronized scholars. The money spent on the Translation Movement for some translations is estimated to be equivalent to twice the annual research budget of the United Kingdom’s Medical Research Council. The best scholars and notable translators, such as Hunayn ibn Ishaq, had salaries that are estimated to be the equivalent of professional athletes today, the House of Wisdom was a library established in Abbasid-era Baghdad, Iraq by Caliph al-Mansur. During this period, the Muslims showed a strong interest in assimilating the knowledge of the civilizations that had been conquered. They also excelled in fields, in particular philosophy, science. For a long period of time the personal physicians of the Abbasid Caliphs were often Assyrian Christians, among the most prominent Christian families to serve as physicians to the caliphs were the Bukhtishu dynasty. Throughout the 4th to 7th centuries, Christian scholarly work in the Greek, the House of Wisdom was founded in Baghdad in 825, modelled after the Academy of Gondishapur. It was led by Christian physician Hunayn ibn Ishaq, with the support of Byzantine medicine, many of the most important philosophical and scientific works of the ancient world were translated, including the work of Galen, Hippocrates, Plato, Aristotle, Ptolemy and Archimedes. Many scholars of the House of Wisdom were of Christian background, the use of paper spread from China into Muslim regions in the eighth century, arriving in Al-Andalus on the Iberian peninsula, present-day Spain in the 10th century. It was easier to manufacture than parchment, less likely to crack than papyrus, Islamic paper makers devised assembly-line methods of hand-copying manuscripts to turn out editions far larger than any available in Europe for centuries. It was from countries that the rest of the world learned to make paper from linen. Ibn Rushd and Ibn Sina played a role in saving the works of Aristotle, whose ideas came to dominate the non-religious thought of the Christian. Ibn Sina and other such as al-Kindi and al-Farabi combined Aristotelianism and Neoplatonism with other ideas introduced through Islam. Arabic philosophic literature was translated into Latin and Ladino, contributing to the development of modern European philosophy, during this period, non-Muslims were allowed to flourish relative to treatment of religious minorities in the Christian Byzantine Empire. The Jewish philosopher Moses Maimonides, who lived in Andalusia, is an example, in epistemology, Ibn Tufail wrote the novel Hayy ibn Yaqdhan and in response Ibn al-Nafis wrote the novel Theologus Autodidactus
8.
Book of Fixed Stars
–
The Book of Fixed Stars is an astronomical text written by Abd al-Rahman al-Sufi around 964. The book was written in Arabic, although the author himself was Persian and it was an attempt to create a synthesis of the comprehensive star catalogue in Ptolemy’s Almagest with the indigenous Arabic astronomical traditions on the constellations. The book was thoroughly illustrated along with observations and descriptions of the stars, their positions, their magnitudes and his results, as in Ptolemys Almagest, were set out constellation by constellation. For each constellation, he provided two drawings, one from the outside of a globe, and the other from the inside. The work was influential and survives in numerous manuscripts and translations. The oldest manuscript, kept in the Bodleian Library, dates to 1009 and is the work of the authors son, there is a thirteenth-century copy in the British Library. He has the earliest known descriptions and illustrations of what he called a little cloud and he mentions it as lying before the mouth of a Big Fish, an Arabic constellation. This cloud was apparently known to the Isfahan astronomers, very probably before 905. The first recorded mention of the Large Magellanic Cloud was also given in the Book of Fixed Stars and these were the first galaxies other than the Milky Way to be observed from Earth. The Great Andromeda Nebula he observed was also the first true nebula to be observed, moreover, he mentions the two Magellanic Clouds, and that they are not visible from Iraq nor Najd, but visible from Tihama, and that they are called al-Baqar. There has not been a published English translation of the book, as of March 2012, one is in preparation by Ihsan Hafez of James Cook University, Townsville. Text and French translation of introduction by J. J. A. Caussin de Perceval in Notices et extraits des manuscrits XII, Paris,1831. Schjellerup, Description des étoiles fixes par Abd-al-Rahman al-Sûfi, St. Petersburg,1874, complete French translation from two late mss. with selected portions in Arabic. Ketāb ṣowar al-kawākeb al-ṯābeta, edited from five mss. and accompanied by the Orǰūza of Ebn al-Ṣūfī, Hyderabad, facsimile edition of the Persian translation by Naṣīr-al-dīn Ṭūsī, Tehran,1348 Š. /1969. Critical edition of Ṭūsīs translation by Sayyed Moʿezz-al-dīn Mahdavī, Tehran,1351 Š. /1972, the Italian translation was edited by P. Knecht, I libri astronomici di Alfonso X in una versione fiorentina del trecento, Saragossa,1965. Paul Kunitzsch, The Arabs and the Stars, Texts and Traditions on the Fixed Stars, Paul Kunitzsch, Ṣūfī Latinus, Zeitschrift der Deutschen Morgenländische Gesellschaft,115,1965, pp. 65–74. Paul Kunitzsch, Al-Ṣūfī in, Dictionary of Scientific Biography, XIII, New York,1976, J. Upton, A Manuscript of “The Book of the Fixed Stars” by ʿAbd ar-Raḥmān aṣ-Ṣūfī, Metropolitan Museum Studies,4,1933, pp. 179–97. E. Wellesz, An Islamic Book of Constellations, Oxford,1965, H. J. J. Winter, Notes on al-Kitab Suwar Al-Kawakib, Archives Internationales d’Histoire des Sciences,8,1955, pp. 126–33
9.
Persian language
–
Persian, also known by its endonym Farsi, is one of the Western Iranian languages within the Indo-Iranian branch of the Indo-European language family. It is primarily spoken in Iran, Afghanistan, and Tajikistan and it is mostly written in the Persian alphabet, a modified variant of the Arabic script. Its grammar is similar to that of many contemporary European languages, Persian gets its name from its origin at the capital of the Achaemenid Empire, Persis, hence the name Persian. A Persian-speaking person may be referred to as Persophone, there are approximately 110 million Persian speakers worldwide, with the language holding official status in Iran, Afghanistan, and Tajikistan. For centuries, Persian has also been a cultural language in other regions of Western Asia, Central Asia. It also exerted influence on Arabic, particularly Bahrani Arabic. Persian is one of the Western Iranian languages within the Indo-European family, other Western Iranian languages are the Kurdish languages, Gilaki, Mazanderani, Talysh, and Balochi. Persian is classified as a member of the Southwestern subgroup within Western Iranian along with Lari, Kumzari, in Persian, the language is known by several names, Western Persian, Parsi or Farsi has been the name used by all native speakers until the 20th century. Since the latter decades of the 20th century, for reasons, in English. Tajiki is the variety of Persian spoken in Tajikistan and Uzbekistan by the Tajiks, according to the Oxford English Dictionary, the term Persian as a language name is first attested in English in the mid-16th century. Native Iranian Persian speakers call it Fārsi, Farsi is the Arabicized form of Pārsi, subsequent to Muslim conquest of Persia, due to a lack of the phoneme /p/ in Standard Arabic. The origin of the name Farsi and the place of origin of the language which is Fars Province is the Arabicized form of Pārs, in English, this language has historically been known as Persian, though Farsi has also gained some currency. Farsi is encountered in some literature as a name for the language. In modern English the word Farsi refers to the language while Parsi describes Zoroastrians, some Persian language scholars such as Ehsan Yarshater, editor of Encyclopædia Iranica, and University of Arizona professor Kamran Talattof, have also rejected the usage of Farsi in their articles. The international language-encoding standard ISO 639-1 uses the code fa, as its system is mostly based on the local names. The more detailed standard ISO 639-3 uses the name Persian for the dialect continuum spoken across Iran and Afghanistan and this consists of the individual languages Dari and Iranian Persian. Currently, Voice of America, BBC World Service, Deutsche Welle, Radio Free Europe/Radio Liberty also includes a Tajik service and an Afghan service. This is also the case for the American Association of Teachers of Persian, The Centre for Promotion of Persian Language and Literature, Persian is an Iranian language belonging to the Indo-Iranian branch of the Indo-European family of languages
10.
Persian people
–
The Persians are an Iranian ethnic group that make up over half the population of Iran. They share a cultural system and are native speakers of the Persian language. The ancient Persians were originally a branch of the ancient Iranian population who entered modern-day Iran by the early 10th century BC. The English term Persian derives from Latin Persia, itself deriving from Greek Persís, in the Bible, it is referred to as Parás —sometimes Paras uMadai —within the books of Esther, Daniel, Ezra and Nehemya. Although Persis was originally one of the provinces of ancient Iran, varieties of this term were adopted through Greek sources, thus, in the Western world, the term Persian came to refer to all inhabitants of the country. 10th-century Iraqi historian Al-Masudi refers to Pahlavi, Dari and Azari as dialects of the Persian language, in 1333, medieval Moroccan traveler and scholar Ibn Battuta, referred to the people of Kabul as a specific sub-tribe of Persians. Lady Mary Sheil, in her observation of Iran during the Qajar era, describes Persians, Kurds and Leks to identify themselves as descendants of the ancient Persians. On March 21,1935, the king of Iran, Reza Shah Pahlavi, issued a decree asking the international community to use the term Iran. However, the term Persian is still used to designate the predominant population of the Iranian peoples living in the Iranian cultural continent. The earliest known written record attributed to the Persians is from the Black Obelisk of Shalmaneser III, the inscription mentions Parsua as a tribal chiefdom in modern-day western Iran. The ancient Persians were originally a branch of the Iranian population that, in the early 10th century BC. They were initially dominated by the Assyrians for much of the first three centuries after arriving in the region, however, they played a role in the downfall of the Neo-Assyrian Empire. The Medes, another branch of population, founded the unified empire of Media as the regions dominant cultural and political power in c.625 BC. Meanwhile, the Persian dynasty of the Achaemenids formed a state to the central Median power. In c.552 BC, the Achaemenids began a revolution which led to the conquest of the empire by Cyrus II in c.550 BC. They spread their influence to the rest of what is called the Iranian Plateau, at its greatest extent, the Achaemenid Empire stretched from parts of Eastern Europe in the west, to the Indus Valley in the east, making it the largest empire the world had yet seen. The Achaemenids developed the infrastructure to support their growing influence, including the creation of Pasargadae and its legacy and impact on the kingdom of Macedon was also notably huge, even for centuries after the withdrawal of the Persians from Europe following the Greco-Persian Wars. The empire collapsed in 330 BC following the conquests of Alexander the Great, until the Parthian era, the Iranian identity had an ethnic, linguistic, and religious value, however, it did not yet have a political import
11.
Western world
–
The Western world or the West is a term usually referring to different nations, depending on the context, most often including at least part of Europe. There are many accepted definitions about what they all have in common, the Western world is also known as the Occident. The concept of the Western part of the earth has its roots in Greco-Roman civilization in Europe, before the Cold War era, the traditional Western viewpoint identified Western Civilization with the Western Christian countries and culture. Its political usage was changed by the antagonism during the Cold War in the mid-to-late 20th Century. The term originally had a literal geographic meaning, Western culture was influenced by many older great civilizations of the ancient Near East, such as Phoenicia, Minoan Crete, Sumer, Babylonia, and also Ancient Egypt. It originated in the Mediterranean basin and its vicinity, Greece, over time, their associated empires grew first to the east and west to include the rest of Mediterranean and Black Sea coastal areas, conquering and absorbing. Later, they expanded to the north of the Mediterranean Sea to include Western, Central, numerous times, this expansion was accompanied by Christian missionaries, who attempted to proselytize Christianity. There is debate among some as to whether Latin America is in a category of its own, specifically, Western culture may imply, a Biblical Christian cultural influence in spiritual thinking, customs and either ethic or moral traditions, around the Post-Classical Era and after. European cultural influences concerning artistic, musical, folkloric, ethic and oral traditions, the concept of Western culture is generally linked to the classical definition of the Western world. In this definition, Western culture is the set of literary, scientific, political, artistic, much of this set of traditions and knowledge is collected in the Western canon. The term has come to apply to countries whose history is marked by European immigration or settlement, such as the Americas, and Oceania. The geopolitical divisions in Europe that created a concept of East and West originated in the Roman Empire, Roman Catholic Western and Central Europe, as such, maintained a distinct identity particularly as it began to redevelop during the Renaissance. Even following the Protestant Reformation, Protestant Europe continued to see itself as more tied to Roman Catholic Europe than other parts of the civilized world. Use of the term West as a cultural and geopolitical term developed over the course of the Age of Exploration as Europe spread its culture to other parts of the world. Additionally, closer contacts between the West and Asia and other parts of the world in recent times have continued to cloud the use, herodotus considered the Persian Wars of the early 5th century BC a conflict of Europa versus Asia. The terms West and East were not used by any Greek author to describe that conflict, the Great Schism and the Fourth Crusade confirmed this deviation. The Renaissance in the West emerged partly from currents within the Roman Empire, Ancient Rome was a civilization that grew from a city-state founded on the Italian Peninsula about the 9th century BC to a massive empire straddling the Mediterranean Sea. In its 12-century existence, Roman civilization shifted from a monarchy, to a republic, nonetheless, despite its great legacy, a number of factors led to the eventual decline of the Roman Empire
12.
Al-Biruni
–
Abū Rayḥān Muḥammad ibn Aḥmad Al-Bīrūnī, known as Al-Biruni in English, was an Iranian scholar and polymath from Khwarezm. He studied almost all fields of science and was compensated for his research, royalty and powerful members of society sought out Al-Biruni to conduct research and study in order to uncover certain findings. He lived during the Islamic Golden Age, in which scholarly thought went hand in hand with the thinking and methodology of the Islamic religion. In addition to type of influence, Al-Biruni was also influenced by other nations, such as the Greek. He was conversant in Khwarezmian, Persian, Arabic, Sanskrit and he spent a large part of his life in Ghazni in modern-day Afghanistan, capital of the Ghaznavid dynasty which was based in what is now central-eastern Afghanistan. In 1017 he traveled to the Indian subcontinent and authored Tarikh Al-Hind after exploring the Hindu faith practised in India and he was given the title founder of Indology. He was a writer on customs and creeds of various nations. He also made contributions to Earth sciences, and is regarded as the father of geodesy for his important contributions to that field and he was born in the outer district of Kath, the capital of the Afrighid dynasty of Khwarezm. The word Biruni means from the outer-district in Persian, and so became his nisba. Al-Birunis relatives also took interest in the studies of science as well and he even had ties to royalty as there are links in his family to the families of prestigious elites. In order to conduct his research, Al-Biruni used different types of methods to tackle the different fields he studied, people consider Al-Biruni to be one of the greatest scientists in history and especially of Islam because of his discoveries and methodology. He lived during the Islamic Golden Age, which promoted astronomy and he was sympathetic to the Afrighids, who were overthrown by the rival dynasty of Mamunids in 995. He left his homeland for Bukhara, then under the Samanid ruler Mansur II the son of Nuh, there he corresponded with Avicenna and there are extant exchanges of views between these two scholars. In 998, he went to the court of the Ziyarid amir of Tabaristan and he also visited the court of the Bavandid ruler Al-Marzuban. Accepting the definite demise of the Afrighids at the hands of the Mamunids and their court at Gorganj was gaining fame for its gathering of brilliant scientists. In 1017, Mahmud of Ghazni took Rey, most scholars, including al-Biruni, were taken to Ghazni, the capital of the Ghaznavid dynasty. Biruni was made court astrologer and accompanied Mahmud on his invasions into India and he was forty-four years old when he went on the journeys with Mahmud of Ghazni. Biruni became acquainted with all related to India
13.
Ecliptic
–
The ecliptic is the apparent path of the Sun on the celestial sphere, and is the basis for the ecliptic coordinate system. It also refers to the plane of this path, which is coplanar with the orbit of Earth around the Sun, the motions as described above are simplifications. Due to the movement of Earth around the Earth–Moon center of mass, due to further perturbations by the other planets of the Solar System, the Earth–Moon barycenter wobbles slightly around a mean position in a complex fashion. The ecliptic is actually the apparent path of the Sun throughout the course of a year, because Earth takes one year to orbit the Sun, the apparent position of the Sun also takes the same length of time to make a complete circuit of the ecliptic. With slightly more than 365 days in one year, the Sun moves a little less than 1° eastward every day, again, this is a simplification, based on a hypothetical Earth that orbits at uniform speed around the Sun. The actual speed with which Earth orbits the Sun varies slightly during the year, for example, the Sun is north of the celestial equator for about 185 days of each year, and south of it for about 180 days. The variation of orbital speed accounts for part of the equation of time, if the equator is projected outward to the celestial sphere, forming the celestial equator, it crosses the ecliptic at two points known as the equinoxes. The Sun, in its apparent motion along the ecliptic, crosses the equator at these points, one from south to north. The crossing from south to north is known as the equinox, also known as the first point of Aries. The crossing from north to south is the equinox or descending node. Likewise, the ecliptic itself is not fixed, the gravitational perturbations of the other bodies of the Solar System cause a much smaller motion of the plane of Earths orbit, and hence of the ecliptic, known as planetary precession. The combined action of two motions is called general precession, and changes the position of the equinoxes by about 50 arc seconds per year. Once again, this is a simplification, periodic motions of the Moon and apparent periodic motions of the Sun cause short-term small-amplitude periodic oscillations of Earths axis, and hence the celestial equator, known as nutation. Obliquity of the ecliptic is the used by astronomers for the inclination of Earths equator with respect to the ecliptic. It is about 23. 4° and is currently decreasing 0.013 degrees per hundred years due to planetary perturbations, the angular value of the obliquity is found by observation of the motions of Earth and other planets over many years. From 1984, the Jet Propulsion Laboratorys DE series of computer-generated ephemerides took over as the ephemeris of the Astronomical Almanac. Obliquity based on DE200, which analyzed observations from 1911 to 1979, was calculated, jPLs fundamental ephemerides have been continually updated. J. Laskar computed an expression to order T10 good to 0″. 04/1000 years over 10,000 years, all of these expressions are for the mean obliquity, that is, without the nutation of the equator included
14.
Sufism
–
Sufism or Taṣawwuf, which is often defined as Islamic mysticism, the inward dimension of Islam, or the phenomenon of mysticism within Islam, is a mystical trend in Islam characterized. These orders meet for sessions in meeting places known as zawiyas, khanqahs. They strive for ihsan as detailed in a hadith, Ihsan is to worship Allah as if you see Him, if you cant see Him, Rumi stated, The Sufi is hanging on to Muhammad, like Abu Bakr. Sufis regard Muhammad as al-Insān al-Kāmil, the perfect man who exemplifies the morality of God. The orders largely follow one of the four madhhabs of Sunni Islam, classical Sufis were characterized by their asceticism, especially by their attachment to dhikr, the practice of repeating the names of God, often performed after prayers. According to William Chittick, In a broad sense, Sufism can be described as the interiorization, historically, Muslims have used the Arabic word taṣawwuf to identify the practice of Sufis. In this view, it is necessary to be a Muslim to be a true Sufi. However, Islamic scholars themselves are not by any means in agreement about the meaning of the word sufi, Sufis themselves claim that Tasawwuf is an aspect of Islam similar to Sharia, inseparable from Islam and an integral part of Islamic belief and practice. Classical Sufi scholars have defined Tasawwuf as a science whose objective is the reparation of the heart and turning it away from all else, two origins of the word sufi have been suggested. Commonly, the root of the word is traced to ṣafā. Another origin is ṣūf, wool in Arabic, referring to the simple cloaks the early Muslim ascetics wore, the two were combined by the Sufi al-Rudhabari, who said, The Sufi is the one who wears wool on top of purity. Scholars generally agree that ṣūf or wool is probably the word of Sufi. This term was given to them because they wore woollen garments, the term labisal-suf meant he clad himself in wool and applied to a person who renounced the world and became an ascetic. Others have suggested that the word comes from the term ahl aṣ-ṣuffah and these men and women who sat at al-Masjid an-Nabawi are considered by some to be the first Sufis. Al-Qushayri and Ibn Khaldun both rejected all other than ṣūf on linguistic grounds. Sufi orders are based on the bayah that was given to the Prophet Muhammad by his Sahaba, by pledging allegiance to the Prophet Muhammad, the Sahaba had committed themselves to the service of God. According to Islamic belief, by pledging allegiance to Prophet Muhammad and it is through the Prophet Muhammad that Sufis aim to learn about, understand and connect with God. Such a concept may be understood by the hadith, which Sufis regard to be authentic, in which Prophet Muhammad said, I am the city of knowledge, eminent Sufis such as Ali Hujwiri refer to Ali as having a very high ranking in Tasawwuf
15.
'Adud al-Dawla
–
He is widely regarded as the greatest monarch of the dynasty, and by the end of his reign was the most powerful ruler in the Middle East. In 974 Adud al-Dawla was sent by his father to save his cousin Izz al-Dawla from a rebellion, after defeating the rebel forces, he claimed the emirate of Iraq for himself, and forced his cousin to abdicate. His father, however, became angered by this decision and restored Izz al-Dawla, after the death of Adud al-Dawlas father, his cousin rebelled against him, but was defeated. Adud al-Dawla became afterwards the sole ruler of the Buyid dynasty, when Adud al-Dawla became emir of Iraq, the capital city, Baghdad, was suffering from violence and instability owing to sectarian conflict. In order to bring peace and stability to the city, he ordered the banning of public demonstrations, at the same time, he patronized a number of Shia scholars such as al-Mufid, and sponsored the renovation of a number of important Shia shrines. In addition, Adud al-Dawla is credited with sponsoring and patronizing other scientific projects during his time, an observatory was built by his orders in Isfahan where Azophi worked. Al-Muqaddasi also reports that he ordered the construction of a dam between Shiraz and Estakhr in 960. The dam irrigated some 300 villages in Fars province and became known as Band-e Amir, among his other major constructions was the digging of the Haffar channel, that joined the Karun river to the Shatt al-Arab river. The port of Khorramshahr was built on the Haffar, at its point with the Shatt al-Arab. Fanna Khusraw was born in Isfahan on September 24,936, he was the son of Rukn al-Dawla, in 948, Fanna Khusraw was chosen by his uncle Imad al-Dawla as his successor because he had no heir. Imad al-Dawla died in December 949, and thus Fanna Khusraw became the new ruler of Fars, however, this appointment was not accepted by a group of Daylamite officers, who shortly rebelled against Fanna Khusraw. Rukn al-Dawla quickly left for southern Iran to save his son, together they defeated the rebels and put Fanna Khusraw on the throne in Shiraz. Fanna Khusraw then requested the title of Taj al-Dawla from the Abbasid caliph, however, to Muizz al-Dawla, the title of Taj implied that Fanna Khusraw was the superior ruler of the Buyid Empire, provoking a reaction from him, and making him decline Fanna Khusraws request. A more suitable title was instead chosen, Adud al-Dawla was only thirteen when he was crowned as the ruler of Fars, and was educated there by his tutor Abu l-Fadl ibn al-Amid. In 955, a Daylamite military officer named Muhammad ibn Makan seized Isfahan from Rukn al-Dawla, Adud al-Dawla then marched towards the city and recaptured it from Muhammad ibn Makan. Another Daylamite military officer named Ruzbahan also shortly rebelled against Muizz al-Dawla, Abu l-Fadl ibn al-Amid, however, managed to suppress the rebellion. In 966, Adud al-Dawla and Muizz al-Dawla made a campaign to impose Buyid rule in Oman, Muizz al-Dawla died in 967, and was succeeded by his eldest son Izz al-Dawla as emir of Iraq. The same year, Adud al-Dawla aided the Ziyarid Bisutun in securing the Ziyarid throne from his brother Qabus, Adud al-Dawla and Bisutun then made an alliance, and Bisutun married a daughter of Adud al-Dawla, while he married a daughter of Bisutun
16.
Iran
–
Iran, also known as Persia, officially the Islamic Republic of Iran, is a sovereign state in Western Asia. Comprising a land area of 1,648,195 km2, it is the second-largest country in the Middle East, with 82.8 million inhabitants, Iran is the worlds 17th-most-populous country. It is the country with both a Caspian Sea and an Indian Ocean coastline. The countrys central location in Eurasia and Western Asia, and its proximity to the Strait of Hormuz, Tehran is the countrys capital and largest city, as well as its leading economic and cultural center. Iran is the site of to one of the worlds oldest civilizations, the area was first unified by the Iranian Medes in 625 BC, who became the dominant cultural and political power in the region. The empire collapsed in 330 BC following the conquests of Alexander the Great, under the Sassanid Dynasty, Iran again became one of the leading powers in the world for the next four centuries. Beginning in 633 AD, Arabs conquered Iran and largely displaced the indigenous faiths of Manichaeism and Zoroastrianism by Islam, Iran became a major contributor to the Islamic Golden Age that followed, producing many influential scientists, scholars, artists, and thinkers. During the 18th century, Iran reached its greatest territorial extent since the Sassanid Empire, through the late 18th and 19th centuries, a series of conflicts with Russia led to significant territorial losses and the erosion of sovereignty. Popular unrest culminated in the Persian Constitutional Revolution of 1906, which established a monarchy and the countrys first legislative body. Following a coup instigated by the U. K. Growing dissent against foreign influence and political repression led to the 1979 Revolution, Irans rich cultural legacy is reflected in part by its 21 UNESCO World Heritage Sites, the third-largest number in Asia and 11th-largest in the world. Iran is a member of the UN, ECO, NAM, OIC. Its political system is based on the 1979 Constitution which combines elements of a democracy with a theocracy governed by Islamic jurists under the concept of a Supreme Leadership. A multicultural country comprising numerous ethnic and linguistic groups, most inhabitants are Shia Muslims, the largest ethnic groups in Iran are the Persians, Azeris, Kurds and Lurs. Historically, Iran has been referred to as Persia by the West, due mainly to the writings of Greek historians who called Iran Persis, meaning land of the Persians. As the most extensive interactions the Ancient Greeks had with any outsider was with the Persians, however, Persis was originally referred to a region settled by Persians in the west shore of Lake Urmia, in the 9th century BC. The settlement was then shifted to the end of the Zagros Mountains. In 1935, Reza Shah requested the international community to refer to the country by its native name, opposition to the name change led to the reversal of the decision, and Professor Ehsan Yarshater, editor of Encyclopædia Iranica, propagated a move to use Persia and Iran interchangeably
17.
Ancient Greece
–
Ancient Greece was a civilization belonging to a period of Greek history from the Greek Dark Ages of the 12th-9th centuries BC to the end of antiquity. Immediately following this period was the beginning of the Early Middle Ages and this was followed by the period of Classical Greece, an era that began with the Greco-Persian Wars, lasting from the 5th to 4th centuries BC. Due to the conquests by Alexander the Great of Macedonia, Hellenistic civilization flourished from Central Asia to the end of the Mediterranean Sea. Classical Greek culture, especially philosophy, had a influence on ancient Rome. For this reason Classical Greece is generally considered to be the culture which provided the foundation of modern Western culture and is considered the cradle of Western civilization. Classical Antiquity in the Mediterranean region is considered to have begun in the 8th century BC. Classical Antiquity in Greece is preceded by the Greek Dark Ages and this period is succeeded, around the 8th century BC, by the Orientalizing Period during which a strong influence of Syro-Hittite, Jewish, Assyrian, Phoenician and Egyptian cultures becomes apparent. The end of the Dark Ages is also dated to 776 BC. The Archaic period gives way to the Classical period around 500 BC, Ancient Periods Astronomical year numbering Dates are approximate, consult particular article for details The history of Greece during Classical Antiquity may be subdivided into five major periods. The earliest of these is the Archaic period, in which artists made larger free-standing sculptures in stiff, the Archaic period is often taken to end with the overthrow of the last tyrant of Athens and the start of Athenian Democracy in 508 BC. It was followed by the Classical period, characterized by a style which was considered by observers to be exemplary, i. e. classical, as shown in the Parthenon. This period saw the Greco-Persian Wars and the Rise of Macedon, following the Classical period was the Hellenistic period, during which Greek culture and power expanded into the Near and Middle East. This period begins with the death of Alexander and ends with the Roman conquest, Herodotus is widely known as the father of history, his Histories are eponymous of the entire field. Herodotus was succeeded by authors such as Thucydides, Xenophon, Demosthenes, Plato, most of these authors were either Athenian or pro-Athenian, which is why far more is known about the history and politics of Athens than those of many other cities. Their scope is limited by a focus on political, military and diplomatic history, ignoring economic. In the 8th century BC, Greece began to emerge from the Dark Ages which followed the fall of the Mycenaean civilization, literacy had been lost and Mycenaean script forgotten, but the Greeks adopted the Phoenician alphabet, modifying it to create the Greek alphabet. The Lelantine War is the earliest documented war of the ancient Greek period and it was fought between the important poleis of Chalcis and Eretria over the fertile Lelantine plain of Euboea. Both cities seem to have suffered a decline as result of the long war, a mercantile class arose in the first half of the 7th century BC, shown by the introduction of coinage in about 680 BC
18.
Almagest
–
The Almagest is the critical source of information on ancient Greek astronomy. It has also been valuable to students of mathematics because it documents the ancient Greek mathematician Hipparchuss work, Hipparchus wrote about trigonometry, but because his works appear to have been lost, mathematicians use Ptolemys book as their source for Hipparchuss work and ancient Greek trigonometry in general. The treatise was later titled Hē Megalē Syntaxis, and the form of this lies behind the Arabic name al-majisṭī. Ptolemy set up a public inscription at Canopus, Egypt, in 147 or 148, the late N. T. Hamilton found that the version of Ptolemys models set out in the Canopic Inscription was earlier than the version in the Almagest. Hence it cannot have been completed before about 150, a century after Ptolemy began observing. The Syntaxis Mathematica consists of thirteen sections, called books, an example illustrating how the Syntaxis was organized is given below. It is a 152-page Latin edition printed in 1515 at Venice by Petrus Lichtenstein, then follows an explanation of chords with table of chords, observations of the obliquity of the ecliptic, and an introduction to spherical trigonometry. There is also a study of the angles made by the ecliptic with the vertical, Book III covers the length of the year, and the motion of the Sun. Ptolemy explains Hipparchus discovery of the precession of the equinoxes and begins explaining the theory of epicycles. Books IV and V cover the motion of the Moon, lunar parallax, the motion of the apogee. Book VI covers solar and lunar eclipses, books VII and VIII cover the motions of the fixed stars, including precession of the equinoxes. They also contain a catalogue of 1022 stars, described by their positions in the constellations. The brightest stars were marked first magnitude, while the faintest visible to the eye were sixth magnitude. Each numerical magnitude was twice the brightness of the following one and this system is believed to have originated with Hipparchus. The stellar positions too are of Hipparchan origin, despite Ptolemys claim to the contrary, Book IX addresses general issues associated with creating models for the five naked eye planets, and the motion of Mercury. Book X covers the motions of Venus and Mars, Book XI covers the motions of Jupiter and Saturn. Book XII covers stations and retrograde motion, which occurs when planets appear to pause, Ptolemy understood these terms to apply to Mercury and Venus as well as the outer planets. Book XIII covers motion in latitude, that is, the deviation of planets from the ecliptic, the cosmology of the Syntaxis includes five main points, each of which is the subject of a chapter in Book I
19.
Ptolemy
–
Claudius Ptolemy was a Greek writer, known as a mathematician, astronomer, geographer, astrologer, and poet of a single epigram in the Greek Anthology. He lived in the city of Alexandria in the Roman province of Egypt, wrote in Koine Greek, beyond that, few reliable details of his life are known. His birthplace has been given as Ptolemais Hermiou in the Thebaid in a statement by the 14th-century astronomer Theodore Meliteniotes. This is a very late attestation, however, and there is no reason to suppose that he ever lived elsewhere than Alexandria. Ptolemy wrote several treatises, three of which were of importance to later Byzantine, Islamic and European science. The first is the astronomical treatise now known as the Almagest, although it was entitled the Mathematical Treatise. The second is the Geography, which is a discussion of the geographic knowledge of the Greco-Roman world. The third is the treatise in which he attempted to adapt horoscopic astrology to the Aristotelian natural philosophy of his day. This is sometimes known as the Apotelesmatika but more known as the Tetrabiblos from the Greek meaning Four Books or by the Latin Quadripartitum. The name Claudius is a Roman nomen, the fact that Ptolemy bore it indicates he lived under the Roman rule of Egypt with the privileges and political rights of Roman citizenship. It would have suited custom if the first of Ptolemys family to become a citizen took the nomen from a Roman called Claudius who was responsible for granting citizenship, if, as was common, this was the emperor, citizenship would have been granted between AD41 and 68. The astronomer would also have had a praenomen, which remains unknown and it occurs once in Greek mythology, and is of Homeric form. All the kings after him, until Egypt became a Roman province in 30 BC, were also Ptolemies, abu Mashar recorded a belief that a different member of this royal line composed the book on astrology and attributed it to Ptolemy. The correct answer is not known”, Ptolemy wrote in Greek and can be shown to have utilized Babylonian astronomical data. He was a Roman citizen, but most scholars conclude that Ptolemy was ethnically Greek and he was often known in later Arabic sources as the Upper Egyptian, suggesting he may have had origins in southern Egypt. Later Arabic astronomers, geographers and physicists referred to him by his name in Arabic, Ptolemys Almagest is the only surviving comprehensive ancient treatise on astronomy. Ptolemy presented his models in convenient tables, which could be used to compute the future or past position of the planets. The Almagest also contains a catalogue, which is a version of a catalogue created by Hipparchus
20.
Star
–
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
21.
Brightness
–
Brightness is an attribute of visual perception in which a source appears to be radiating or reflecting light. In other words, brightness is the perception elicited by the luminance of a visual target and it is not necessarily proportional to luminance. This is a subjective attribute/property of an object being observed and one of the color appearance parameters of color appearance models, brightness refers to an absolute term and should not be confused with Lightness. The adjective bright derives from an Old English beorht with the same meaning via metathesis giving Middle English briht, the word is from a Common Germanic *berhtaz, ultimately from a PIE root with a closely related meaning, *bhereg- white, bright. Brightness was formerly used as a synonym for the term luminance. As defined by the US Federal Glossary of Telecommunication Terms, brightness should now be used only for non-quantitative references to physiological sensations and perceptions of light, a given target luminance can elicit different perceptions of brightness in different contexts, see, for example, Whites illusion. With regard to stars, brightness is quantified as apparent magnitude, brightness is, at least in some respects, the antonym of darkness. The United States Federal Trade Commission has assigned a meaning to brightness when applied to lamps. When appearing on light bulb packages, brightness means Luminous flux, Luminous flux is the total amount of light coming from a source, such as a lighting device. Luminance, the meaning of brightness, is the amount of light per solid angle coming from an area. The table below shows the ways of indicating the amount of light. The term brightness is used in discussions of sound timbres. Luma Luminance Luminosity Media related to brightness at Wikimedia Commons Poyntons Color FAQ
22.
Apparent magnitude
–
The apparent magnitude of a celestial object is a number that is a measure of its brightness as seen by an observer on Earth. The brighter an object appears, the lower its magnitude value, the Sun, at apparent magnitude of −27, is the brightest object in the sky. It is adjusted to the value it would have in the absence of the atmosphere, furthermore, the magnitude scale is logarithmic, a difference of one in magnitude corresponds to a change in brightness by a factor of 5√100, or about 2.512. The measurement of apparent magnitudes or brightnesses of celestial objects is known as photometry, apparent magnitudes are used to quantify the brightness of sources at ultraviolet, visible, and infrared wavelengths. An apparent magnitude is measured in a specific passband corresponding to some photometric system such as the UBV system. In standard astronomical notation, an apparent magnitude in the V filter band would be denoted either as mV or often simply as V, the scale used to indicate magnitude originates in the Hellenistic practice of dividing stars visible to the naked eye into six magnitudes. The brightest stars in the sky were said to be of first magnitude, whereas the faintest were of sixth magnitude. Each grade of magnitude was considered twice the brightness of the following grade and this rather crude scale for the brightness of stars was popularized by Ptolemy in his Almagest, and is generally believed to have originated with Hipparchus. This implies that a star of magnitude m is 2.512 times as bright as a star of magnitude m +1 and this figure, the fifth root of 100, became known as Pogsons Ratio. The zero point of Pogsons scale was defined by assigning Polaris a magnitude of exactly 2. However, with the advent of infrared astronomy it was revealed that Vegas radiation includes an Infrared excess presumably due to a disk consisting of dust at warm temperatures. At shorter wavelengths, there is negligible emission from dust at these temperatures, however, in order to properly extend the magnitude scale further into the infrared, this peculiarity of Vega should not affect the definition of the magnitude scale. Therefore, the scale was extrapolated to all wavelengths on the basis of the black body radiation curve for an ideal stellar surface at 11000 K uncontaminated by circumstellar radiation. On this basis the spectral irradiance for the zero magnitude point, with the modern magnitude systems, brightness over a very wide range is specified according to the logarithmic definition detailed below, using this zero reference. In practice such apparent magnitudes do not exceed 30, astronomers have developed other photometric zeropoint systems as alternatives to the Vega system. The AB magnitude zeropoint is defined such that an objects AB, the dimmer an object appears, the higher the numerical value given to its apparent magnitude, with a difference of 5 magnitudes corresponding to a brightness factor of exactly 100. Since an increase of 5 magnitudes corresponds to a decrease in brightness by a factor of exactly 100, each magnitude increase implies a decrease in brightness by the factor 5√100 ≈2.512. Inverting the above formula, a magnitude difference m1 − m2 = Δm implies a brightness factor of F2 F1 =100 Δ m 5 =100.4 Δ m ≈2.512 Δ m
23.
Hellenistic period
–
It is often considered a period of transition, sometimes even of decadence or degeneration, compared to the enlightenment of the Greek Classical era. The Hellenistic period saw the rise of New Comedy, Alexandrian poetry, the Septuagint, Greek science was advanced by the works of the mathematician Euclid and the polymath Archimedes. The religious sphere expanded to include new gods such as the Greco-Egyptian Serapis, eastern deities such as Attis and Cybele, the Hellenistic period was characterized by a new wave of Greek colonization which established Greek cities and kingdoms in Asia and Africa. This resulted in the export of Greek culture and language to new realms. Equally, however, these new kingdoms were influenced by the cultures, adopting local practices where beneficial, necessary. Hellenistic culture thus represents a fusion of the Ancient Greek world with that of the Near East, Middle East and this mixture gave rise to a common Attic-based Greek dialect, known as Koine Greek, which became the lingua franca through the Hellenistic world. Scholars and historians are divided as to what event signals the end of the Hellenistic era, Hellenistic is distinguished from Hellenic in that the first encompasses the entire sphere of direct ancient Greek influence, while the latter refers to Greece itself. The word originated from the German term hellenistisch, from Ancient Greek Ἑλληνιστής, from Ἑλλάς, Hellenistic is a modern word and a 19th-century concept, the idea of a Hellenistic period did not exist in Ancient Greece. Although words related in form or meaning, e. g, the major issue with the term Hellenistic lies in its convenience, as the spread of Greek culture was not the generalized phenomenon that the term implies. Some areas of the world were more affected by Greek influences than others. The Greek population and the population did not always mix, the Greeks moved and brought their own culture. While a few fragments exist, there is no surviving historical work which dates to the hundred years following Alexanders death. The works of the major Hellenistic historians Hieronymus of Cardia, Duris of Samos, the earliest and most credible surviving source for the Hellenistic period is Polybius of Megalopolis, a statesman of the Achaean League until 168 BC when he was forced to go to Rome as a hostage. His Histories eventually grew to a length of forty books, covering the years 220 to 167 BC, another important source, Plutarchs Parallel Lives though more preoccupied with issues of personal character and morality, outlines the history of important Hellenistic figures. Appian of Alexandria wrote a history of the Roman empire that includes information of some Hellenistic kingdoms, other sources include Justins epitome of Pompeius Trogus Historiae Philipicae and a summary of Arrians Events after Alexander, by Photios I of Constantinople. Lesser supplementary sources include Curtius Rufus, Pausanias, Pliny, in the field of philosophy, Diogenes Laertius Lives and Opinions of Eminent Philosophers is the main source. Ancient Greece had traditionally been a collection of fiercely independent city-states. After the Peloponnesian War, Greece had fallen under a Spartan hegemony, in which Sparta was pre-eminent but not all-powerful
24.
Alexandria
–
Alexandria is the second largest city and a major economic centre in Egypt, extending about 32 km along the coast of the Mediterranean Sea in the north central part of the country. Its low elevation on the Nile delta makes it vulnerable to rising sea levels. Alexandria is Egypts largest seaport, serving approximately 80% of Egypts imports and exports and it is an important industrial center because of its natural gas and oil pipelines from Suez. Alexandria is also an important tourist destination, Alexandria was founded around a small Ancient Egyptian town c.331 BC by Alexander the Great. Alexandria was the second most powerful city of the ancient world after Rome, Alexandria is believed to have been founded by Alexander the Great in April 331 BC as Ἀλεξάνδρεια. Alexanders chief architect for the project was Dinocrates, Alexandria was intended to supersede Naucratis as a Hellenistic center in Egypt, and to be the link between Greece and the rich Nile valley. The city and its museum attracted many of the greatest scholars, including Greeks, Jews, the city was later plundered and lost its significance. Just east of Alexandria, there was in ancient times marshland, as early as the 7th century BC, there existed important port cities of Canopus and Heracleion. The latter was rediscovered under water. An Egyptian city, Rhakotis, already existed on the shore also and it continued to exist as the Egyptian quarter of the city. A few months after the foundation, Alexander left Egypt and never returned to his city, after Alexanders departure, his viceroy, Cleomenes, continued the expansion. Although Cleomenes was mainly in charge of overseeing Alexandrias continuous development, the Heptastadion, inheriting the trade of ruined Tyre and becoming the center of the new commerce between Europe and the Arabian and Indian East, the city grew in less than a generation to be larger than Carthage. In a century, Alexandria had become the largest city in the world and and it became Egypts main Greek city, with Greek people from diverse backgrounds. Alexandria was not only a center of Hellenism, but was home to the largest urban Jewish community in the world. The Septuagint, a Greek version of the Tanakh, was produced there, in AD115, large parts of Alexandria were destroyed during the Kitos War, which gave Hadrian and his architect, Decriannus, an opportunity to rebuild it. On 21 July 365, Alexandria was devastated by a tsunami, the Islamic prophet, Muhammads first interaction with the people of Egypt occurred in 628, during the Expedition of Zaid ibn Haritha. He sent Hatib bin Abi Baltaeh with a letter to the king of Egypt and Alexandria called Muqawqis In the letter Muhammad said, I invite you to accept Islam, Allah the sublime, shall reward you doubly. But if you refuse to do so, you bear the burden of the transgression of all the Copts
25.
Egypt
–
Egypt, officially the Arab Republic of Egypt, is a transcontinental country spanning the northeast corner of Africa and southwest corner of Asia by a land bridge formed by the Sinai Peninsula. Egypt is a Mediterranean country bordered by the Gaza Strip and Israel to the northeast, the Gulf of Aqaba to the east, the Red Sea to the east and south, Sudan to the south, and Libya to the west. Across the Gulf of Aqaba lies Jordan, and across from the Sinai Peninsula lies Saudi Arabia, although Jordan and it is the worlds only contiguous Afrasian nation. Egypt has among the longest histories of any country, emerging as one of the worlds first nation states in the tenth millennium BC. Considered a cradle of civilisation, Ancient Egypt experienced some of the earliest developments of writing, agriculture, urbanisation, organised religion and central government. One of the earliest centres of Christianity, Egypt was Islamised in the century and remains a predominantly Muslim country. With over 92 million inhabitants, Egypt is the most populous country in North Africa and the Arab world, the third-most populous in Africa, and the fifteenth-most populous in the world. The great majority of its people live near the banks of the Nile River, an area of about 40,000 square kilometres, the large regions of the Sahara desert, which constitute most of Egypts territory, are sparsely inhabited. About half of Egypts residents live in areas, with most spread across the densely populated centres of greater Cairo, Alexandria. Modern Egypt is considered to be a regional and middle power, with significant cultural, political, and military influence in North Africa, the Middle East and the Muslim world. Egypts economy is one of the largest and most diversified in the Middle East, Egypt is a member of the United Nations, Non-Aligned Movement, Arab League, African Union, and Organisation of Islamic Cooperation. Miṣr is the Classical Quranic Arabic and modern name of Egypt. The name is of Semitic origin, directly cognate with other Semitic words for Egypt such as the Hebrew מִצְרַיִם, the oldest attestation of this name for Egypt is the Akkadian
26.
Greek language
–
Greek is an independent branch of the Indo-European family of languages, native to Greece and other parts of the Eastern Mediterranean. It has the longest documented history of any living language, spanning 34 centuries of written records and its writing system has been the Greek alphabet for the major part of its history, other systems, such as Linear B and the Cypriot syllabary, were used previously. The alphabet arose from the Phoenician script and was in turn the basis of the Latin, Cyrillic, Armenian, Coptic, Gothic and many other writing systems. Together with the Latin texts and traditions of the Roman world, during antiquity, Greek was a widely spoken lingua franca in the Mediterranean world and many places beyond. It would eventually become the official parlance of the Byzantine Empire, the language is spoken by at least 13.2 million people today in Greece, Cyprus, Italy, Albania, Turkey, and the Greek diaspora. Greek roots are used to coin new words for other languages, Greek. Greek has been spoken in the Balkan peninsula since around the 3rd millennium BC, the earliest written evidence is a Linear B clay tablet found in Messenia that dates to between 1450 and 1350 BC, making Greek the worlds oldest recorded living language. Among the Indo-European languages, its date of earliest written attestation is matched only by the now extinct Anatolian languages, the Greek language is conventionally divided into the following periods, Proto-Greek, the unrecorded but assumed last ancestor of all known varieties of Greek. The unity of Proto-Greek would have ended as Hellenic migrants entered the Greek peninsula sometime in the Neolithic era or the Bronze Age, Mycenaean Greek, the language of the Mycenaean civilisation. It is recorded in the Linear B script on tablets dating from the 15th century BC onwards, Ancient Greek, in its various dialects, the language of the Archaic and Classical periods of the ancient Greek civilisation. It was widely known throughout the Roman Empire, after the Roman conquest of Greece, an unofficial bilingualism of Greek and Latin was established in the city of Rome and Koine Greek became a first or second language in the Roman Empire. The origin of Christianity can also be traced through Koine Greek, Medieval Greek, also known as Byzantine Greek, the continuation of Koine Greek in Byzantine Greece, up to the demise of the Byzantine Empire in the 15th century. Much of the written Greek that was used as the language of the Byzantine Empire was an eclectic middle-ground variety based on the tradition of written Koine. Modern Greek, Stemming from Medieval Greek, Modern Greek usages can be traced in the Byzantine period and it is the language used by the modern Greeks, and, apart from Standard Modern Greek, there are several dialects of it. In the modern era, the Greek language entered a state of diglossia, the historical unity and continuing identity between the various stages of the Greek language is often emphasised. Greek speakers today still tend to regard literary works of ancient Greek as part of their own rather than a foreign language and it is also often stated that the historical changes have been relatively slight compared with some other languages. According to one estimation, Homeric Greek is probably closer to demotic than 12-century Middle English is to modern spoken English, Greek is spoken by about 13 million people, mainly in Greece, Albania and Cyprus, but also worldwide by the large Greek diaspora. Greek is the language of Greece, where it is spoken by almost the entire population
27.
Arabic
–
Arabic is a Central Semitic language that was first spoken in Iron Age northwestern Arabia and is now the lingua franca of the Arab world. Arabic is also the language of 1.7 billion Muslims. It is one of six languages of the United Nations. The modern written language is derived from the language of the Quran and it is widely taught in schools and universities, and is used to varying degrees in workplaces, government, and the media. The two formal varieties are grouped together as Literary Arabic, which is the language of 26 states. Modern Standard Arabic largely follows the standards of Quranic Arabic. Much of the new vocabulary is used to denote concepts that have arisen in the post-Quranic era, Arabic has influenced many languages around the globe throughout its history. During the Middle Ages, Literary Arabic was a vehicle of culture in Europe, especially in science, mathematics. As a result, many European languages have borrowed many words from it. Many words of Arabic origin are found in ancient languages like Latin. Balkan languages, including Greek, have acquired a significant number of Arabic words through contact with Ottoman Turkish. Arabic has also borrowed words from languages including Greek and Persian in medieval times. Arabic is a Central Semitic language, closely related to the Northwest Semitic languages, the Ancient South Arabian languages, the Semitic languages changed a great deal between Proto-Semitic and the establishment of the Central Semitic languages, particularly in grammar. Innovations of the Central Semitic languages—all maintained in Arabic—include, The conversion of the suffix-conjugated stative formation into a past tense, the conversion of the prefix-conjugated preterite-tense formation into a present tense. The elimination of other prefix-conjugated mood/aspect forms in favor of new moods formed by endings attached to the prefix-conjugation forms, the development of an internal passive. These features are evidence of descent from a hypothetical ancestor. In the southwest, various Central Semitic languages both belonging to and outside of the Ancient South Arabian family were spoken and it is also believed that the ancestors of the Modern South Arabian languages were also spoken in southern Arabia at this time. To the north, in the oases of northern Hijaz, Dadanitic and Taymanitic held some prestige as inscriptional languages, in Najd and parts of western Arabia, a language known to scholars as Thamudic C is attested
28.
Constellation
–
A constellation is formally defined as a region of the celestial sphere, with boundaries laid down by the International Astronomical Union. The constellation areas mostly had their origins in Western-traditional patterns of stars from which the constellations take their names, in 1922, the International Astronomical Union officially recognized the 88 modern constellations, which cover the entire sky. They began as the 48 classical Greek constellations laid down by Ptolemy in the Almagest, Constellations in the far southern sky are late 16th- and mid 18th-century constructions. 12 of the 88 constellations compose the zodiac signs, though the positions of the constellations only loosely match the dates assigned to them in astrology. The term constellation can refer to the stars within the boundaries of that constellation. Notable groupings of stars that do not form a constellation are called asterisms, when astronomers say something is “in” a given constellation they mean it is within those official boundaries. Any given point in a coordinate system can unambiguously be assigned to a single constellation. Many astronomical naming systems give the constellation in which an object is found along with a designation in order to convey a rough idea in which part of the sky it is located. For example, the Flamsteed designation for bright stars consists of a number, the word constellation seems to come from the Late Latin term cōnstellātiō, which can be translated as set of stars, and came into use in English during the 14th century. It also denotes 88 named groups of stars in the shape of stellar-patterns, the Ancient Greek word for constellation was ἄστρον. Colloquial usage does not draw a distinction between constellation in the sense of an asterism and constellation in the sense of an area surrounding an asterism. The modern system of constellations used in astronomy employs the latter concept, the term circumpolar constellation is used for any constellation that, from a particular latitude on Earth, never sets below the horizon. From the North Pole or South Pole, all constellations south or north of the equator are circumpolar constellations. In the equatorial or temperate latitudes, the term equatorial constellation has sometimes been used for constellations that lie to the opposite the circumpolar constellations. They generally include all constellations that intersect the celestial equator or part of the zodiac, usually the only thing the stars in a constellation have in common is that they appear near each other in the sky when viewed from the Earth. In galactic space, the stars of a constellation usually lie at a variety of distances, since stars also travel on their own orbits through the Milky Way, the star patterns of the constellations change slowly over time. After tens to hundreds of thousands of years, their familiar outlines will become unrecognisable, the terms chosen for the constellation themselves, together with the appearance of a constellation, may reveal where and when its constellation makers lived. The earliest direct evidence for the constellations comes from inscribed stones and it seems that the bulk of the Mesopotamian constellations were created within a relatively short interval from around 1300 to 1000 BC
29.
Sagittarius (constellation)
–
Sagittarius is one of the constellations of the zodiac. It is one of the 48 constellations listed by the 2nd-century astronomer Ptolemy and its name is Latin for the archer, and its symbol is, a stylized arrow. Sagittarius is commonly represented as a centaur pulling-back a bow and it lies between Scorpius and Ophiuchus to the west and Capricornus to the east. The center of the Milky Way lies in the westernmost part of Sagittarius, as seen from the northern hemisphere, the constellations brighter stars form an easily recognizable asterism known as the Teapot. The stars δ Sgr, ε Sgr, ζ Sgr, and φ Sgr form the body of the pot, λ Sgr is the point of the lid, γ2 Sgr is the tip of the spout and these same stars originally formed the bow and arrow of Sagittarius. Marking the bottom of the teapots handle (or the shoulder area of the archer, are the bright star Zeta Sagittarii, named Ascella, and the fainter Tau Sagittarii. The constellation as a whole is often depicted as having the appearance of a stick-figure archer drawing its bow. Sagittarius famously points its arrow at the heart of Scorpius, represented by the reddish star Antares, following the direct line formed by Delta Sagittarii and Gamma2 Sagittarii leads nearly directly to Antares. Fittingly, Sagittarii is Alnasl, the Arabic word for arrowhead, and Delta Sagittarii is called Kaus Media, Kaus Media bisects Lambda Sagittarii and Epsilon Sagittarii, whose names Kaus Borealis and Kaus Australis refer to the northern and southern portions of the bow, respectively. α Sgr despite having the alpha appellation, is not the brightest star of the constellation, instead, the brightest star is Epsilon Sagittarii, at magnitude 1.85. Sigma Sagittarii is the constellations second-brightest star at magnitude 2.08, Nunki is a B2V star approximately 260 light years away. Nunki is a Babylonian name of origin, but thought to represent the sacred Babylonian city of Eridu on the Euphrates. Zeta Sagittarii, with apparent magnitude 2.61 of A2 spectra, is actually a star whose two components have magnitudes 3.3 and 3.5. Delta Sagittarii, is a K2 spectra star with magnitude 2.71 and only 85 light years from Earth. Eta Sagittarii is a star with component magnitudes of 3.18 and 10, while Pi Sagittarii is actually a triple system whose components have magnitudes 3.7,3.8. The Bayer designation Beta Sagittarii is shared by two systems, β¹ Sagittarii, with apparent magnitude 3.96, and β² Sagittarii. The two stars are separated by 0. 36° in the sky and are 378 light years from earth, Beta Sagittarii, located at a position associated with the forelegs of the centaur, has the traditional name Arkab, meaning achilles tendon. Nova Sagittarii 2015 No.2 was discovered on March 15,2015, by John Seach of Chatsworth Island, NSW and it lies near the center of the constellation
30.
Large Magellanic Cloud
–
The Large Magellanic Cloud is a satellite galaxy of the Milky Way. The LMC has a diameter of about 14,000 light-years, the LMC is the fourth-largest galaxy in the Local Group, after the Andromeda Galaxy, the Milky Way, and the Triangulum Galaxy. The LMC is classified as a Magellanic spiral and it contains a very prominent bar in its center, suggesting that it may have been a barred dwarf spiral galaxy before its spiral arms were disrupted, likely by the Milky Ways gravity. The LMCs present irregular appearance is likely the result of interactions with both the Milky Way and the Small Magellanic Cloud. The first recorded mention of the Large Magellanic Cloud was by the Persian astronomer Abd al-Rahman al-Sufi Shirazi, the next recorded observation was in 1503–4 by Amerigo Vespucci in a letter about his third voyage. In this letter he mentions three Canopes, two bright and one obscure, bright refers to the two Magellanic Clouds, and obscure refers to the Coalsack, ferdinand Magellan sighted the LMC on his voyage in 1519, and his writings brought the LMC into common Western knowledge. The galaxy now bears his name, measurements with the Hubble Space Telescope, announced in 2006, suggest the Large and Small Magellanic Clouds may be moving too fast to be orbiting the Milky Way. The Large Magellanic Cloud is usually considered an irregular galaxy, however, it shows signs of a bar structure, and is often reclassified as a Magellanic-type dwarf spiral galaxy. The Large Magellanic Cloud has a prominent central bar and a spiral arm, the central bar seems to be warped so that the east and west ends are nearer the Milky Way than the middle. In 2014, measurements from the Hubble Space Telescope made it possible to determine that the LMC has a period of 250 million years. The LMC was long considered to be a galaxy that could be assumed to lie at a single distance from the Solar System. However, in 1986, Caldwell and Coulson found that field Cepheid variables in the northeast portion of the LMC lie closer to the Milky Way than Cepheids in the southwest portion. More recently, this inclined geometry for field stars in the LMC has been confirmed via observations of Cepheids, core helium-burning red clump stars, all three of these papers find an inclination of ~35°, where a face-on galaxy has an inclination of 0°. Further work on the structure of the LMC using the kinematics of stars showed that the LMCs disk is both thick and flared. These results were confirmed by Grocholski et al. who calculated distances to a number of clusters, the distance to the LMC has been calculated using a variety of standard candles, with Cepheid variables being one of the most popular. Cepheids have been shown to have a relationship between their absolute luminosity and the period over which their brightness varies, however, Cepheids appear to suffer from a metallicity effect, where Cepheids of different metallicities have different period–luminosity relations. Unfortunately, the Cepheids in the Milky Way typically used to calibrate the period–luminosity relation are more rich than those found in the LMC. Modern 8-meter-class optical telescopes have discovered eclipsing binaries throughout the Local Group, parameters of these systems can be measured without mass or compositional assumptions
31.
Yemen
–
Yemen, officially known as the Republic of Yemen, is an Arab country in Western Asia, occupying South Arabia, the southern end of the Arabian Peninsula. Yemen is the second-largest country in the peninsula, occupying 527,970 km2, the coastline stretches for about 2,000 km. It is bordered by Saudi Arabia to the north, the Red Sea to the west, the Gulf of Aden and Arabian Sea to the south, although Yemens constitutionally stated capital is the city of Sanaa, the city has been under rebel control since February 2015. Because of this, Yemens capital has been relocated to the port city of Aden. Yemens territory includes more than 200 islands, the largest of these is Socotra, Yemen was the home of the Sabaeans, a trading state that flourished for over a thousand years and probably also included parts of modern-day Ethiopia and Eritrea. In 275 AD, the region came under the rule of the later Jewish-influenced Himyarite Kingdom, Christianity arrived in the fourth century, whereas Judaism and local paganism were already established. Islam spread quickly in the century and Yemenite troops were crucial in the expansion of the early Islamic conquests. Administration of Yemen has long been notoriously difficult, several dynasties emerged from the ninth to 16th centuries, the Rasulid dynasty being the strongest and most prosperous. The country was divided between the Ottoman and British empires in the twentieth century. The Zaydi Mutawakkilite Kingdom of Yemen was established after World War I in North Yemen before the creation of the Yemen Arab Republic in 1962, South Yemen remained a British protectorate known as the Aden Protectorate until 1967 when it became an independent state and later, a Marxist state. The two Yemeni states united to form the modern republic of Yemen in 1990, Yemen is a developing country, and the poorest country in the Middle East. Under the rule of President Ali Abdullah Saleh, Yemen was described as a kleptocracy, according to the 2009 international corruption Perception Index by Transparency International, Yemen ranked 164 out of 182 countries surveyed. President Saleh stepped down and the powers of the presidency were transferred to Vice President Abd Rabbuh Mansur Hadi, the transitional process was disrupted by conflicts between the Houthis and al-Islah, as well as the al-Qaeda insurgency. In September 2014, the Houthis took over Sanaa, later declaring themselves in control of the government in a coup détat, since then, a Saudi-led intervention has taken place, however, it could not stop the civil war. Instead, the Saudis and the others have destroyed some hospitals, schools and homes, Yemen was mentioned in Old South Arabian inscriptions as Yamnat. In Arabic literature, the term includes much greater territory than that of the republic of Yemen. It stretches from the northern Asir Region in southwestern Saudi Arabia to Dhofar Governorate in southern Oman, one etymology derives Yemen from yumn, meaning felicity, as much of the country is fertile. The Romans called it Arabia Felix, as opposed to Arabia Deserta, al-Yaman significantly plays on the notion of the land to the right, when in Mecca facing the dawn, complementary to Al-Sham, the Land to the Left, referring to the Levant
32.
Ferdinand Magellan
–
Commanding a fleet of five vessels, he headed south through the Atlantic Ocean to Patagonia, passing through the Strait of Magellan into a body of water he named the peaceful sea. Despite a series of storms and mutinies, the reached the Spice Islands in 1521. Magellan did not complete the voyage, as he was killed during the Battle of Mactan in the Philippines in 1521. Magellan had already reached the Malay Archipelago in Southeast Asia on previous voyages traveling east, by visiting this area again but now travelling west, Magellan achieved a nearly complete personal circumnavigation of the globe for the first time in history. The Magellanic penguin is named after him, as he was the first European to note it. Magellan was born in northern Portugal in around 1480, either at Vila Nova de Gaia, near Porto, in Douro Litoral Province, or at Sabrosa, near Vila Real, in Trás-os-Montes e Alto Douro Province. He was the son of Rodrigo de Magalhães, Alcaide-Mor of Aveiro and wife Alda de Mesquita and brother of Leonor or Genebra de Magalhães, in March 1505 at the age of 25, Magellan enlisted in the fleet of 22 ships sent to host D. Francisco de Almeida as the first viceroy of Portuguese India, although his name does not appear in the chronicles, it is known that he remained there eight years, in Goa, Cochin and Quilon. He participated in battles, including the battle of Cannanore in 1506. In 1509 he fought in the battle of Diu and he later sailed under Diogo Lopes de Sequeira in the first Portuguese embassy to Malacca, with Francisco Serrão, his friend and possibly cousin. In September, after arriving at Malacca, the expedition fell victim to an ending in retreat. Magellan had a role, warning Sequeira and saving Francisco Serrão. In 1511, under the new governor Afonso de Albuquerque, Magellan, after the conquest their ways parted, Magellan was promoted, with a rich plunder and, in the company of a Malay he had indentured and baptized Enrique of Malacca, he returned to Portugal in 1512. Serrão departed in the first expedition sent to find the Spice Islands in the Moluccas and he married a woman from Amboina and became a military advisor to the Sultan of Ternate, Bayan Sirrullah. His letters to Magellan would prove decisive, giving information about the spice-producing territories, after taking a leave without permission, Magellan fell out of favour. Serving in Morocco, he was wounded, resulting in a permanent limp and he was accused of trading illegally with the Moors. The accusations were proved false, but he received no offers of employment after 15 May 1514. Later on in 1515, he got an employment offer as a member on a Portuguese ship
33.
Andromeda Galaxy
–
The Andromeda Galaxy, also known as Messier 31, M31, or NGC224, is a spiral galaxy approximately 780 kiloparsecs from Earth. It is the nearest major galaxy to the Milky Way and was referred to as the Great Andromeda Nebula in older texts. It received its name from the area of the sky in which it appears, the constellation of Andromeda, which was named after the mythological princess Andromeda. Andromeda is approximately 220,000 light years across, and it is the largest galaxy of the Local Group, which contains the Milky Way, the Triangulum Galaxy. The mass of the Andromeda Galaxy is estimated to be 1. 5×1012 solar masses, the Milky Way and Andromeda galaxies are expected to collide in 4.5 billion years, eventually merging to form a giant elliptical galaxy or perhaps a large disc galaxy. Around the year 964, the Persian astronomer Abd al-Rahman al-Sufi described the Andromeda Galaxy, star charts of that period labeled it as the Little Cloud. In 1612, the German astronomer Simon Marius gave a description of the Andromeda Galaxy based on telescopic observations. In 1764, Charles Messier catalogued Andromeda as object M31 and incorrectly credited Marius as the discoverer despite it being visible to the naked eye, in 1785, the astronomer William Herschel noted a faint reddish hue in the core region of Andromeda. In 1850, William Parsons, 3rd Earl of Rosse, saw, in 1864, William Huggins noted that the spectrum of Andromeda differs from a gaseous nebula. The spectra of Andromeda displays a continuum of frequencies, superimposed with dark lines that help identify the chemical composition of an object. Andromedas spectrum is similar to the spectra of individual stars. In 1885, a supernova was seen in Andromeda, the first, at the time Andromeda was considered to be a nearby object, so the cause was thought to be a much less luminous and unrelated event called a nova, and was named accordingly, Nova 1885. In 1887, Isaac Roberts took the first photographs of Andromeda, Roberts actually mistook Andromeda and similar spiral nebulae as solar systems being formed. In 1912, Vesto Slipher used spectroscopy to measure the velocity of Andromeda with respect to our solar system—the largest velocity yet measured. In 1917, Heber Curtis observed a nova within Andromeda, searching the photographic record,11 more novae were discovered. Curtis noticed that these novae were, on average,10 magnitudes fainter than those that occurred elsewhere in the sky, as a result, he was able to come up with a distance estimate of 500,000 light-years. He became a proponent of the island universes hypothesis, which held that spiral nebulae were actually independent galaxies. In 1920, the Great Debate between Harlow Shapley and Curtis took place, concerning the nature of the Milky Way, spiral nebulae, in 1922 Ernst Öpik presented a method to estimate the distance of Andromeda using the measured velocities of its stars
34.
Galaxy
–
A galaxy is a gravitationally bound system of stars, stellar remnants, interstellar gas, dust, and dark matter. The word galaxy is derived from the Greek galaxias, literally milky, Galaxies range in size from dwarfs with just a few billion stars to giants with one hundred trillion stars, each orbiting its galaxys center of mass. Galaxies are categorized according to their morphology as elliptical, spiral. Many galaxies are thought to have holes at their active centers. The Milky Ways central black hole, known as Sagittarius A*, has a four million times greater than the Sun. Recent estimates of the number of galaxies in the observable universe range from 200 billion to 2 trillion or more, most of the galaxies are 1,000 to 100,000 parsecs in diameter and separated by distances on the order of millions of parsecs. The space between galaxies is filled with a gas having an average density of less than one atom per cubic meter. The majority of galaxies are organized into groups, clusters. At the largest scale, these associations are generally arranged into sheets and filaments surrounded by immense voids. In Greek mythology, Zeus places his son born by a mortal woman, the infant Heracles, on Heras breast while she is asleep so that the baby will drink her divine milk and will thus become immortal. Hera wakes up while breastfeeding and then realizes she is nursing a baby, she pushes the baby away, some of her milk spills and. In the astronomical literature, the capitalized word Galaxy is often used to refer to our galaxy, the Milky Way, to distinguish it from the other galaxies in our universe. The English term Milky Way can be traced back to a story by Chaucer c. 1380, See yonder, lo, the Galaxyë Which men clepeth the Milky Wey, For hit is whyt. However, the word Universe was later understood to mean the entirety of existence, so this expression fell into disuse and the objects instead became known as galaxies. Tens of thousands of galaxies have been catalogued, but only a few have well-established names, such as the Andromeda Galaxy, the Magellanic Clouds, the Whirlpool Galaxy, and the Sombrero Galaxy. Astronomers work with numbers from certain catalogues, such as the Messier catalogue, the NGC, the IC, the CGCG, all of the well-known galaxies appear in one or more of these catalogues but each time under a different number. For example, Messier 109 is a galaxy having the number 109 in the catalogue of Messier, but also codes NGC3992, UGC6937, CGCG 269-023, MCG +09-20-044. One of the arguments to do so is that these impressive objects deserve better than uninspired codes, for instance, Bodifee and Berger propose the informal, descriptive name Callimorphus Ursae Majoris for the well-formed barred galaxy Messier 109 in Ursa Major
35.
Milky Way
–
The Milky Way is the galaxy that contains our Solar System. The descriptive milky is derived from the appearance from Earth of the galaxy – a band of light seen in the night sky formed from stars that cannot be distinguished by the naked eye. The term Milky Way is a translation of the Latin via lactea, from Earth, the Milky Way appears as a band because its disk-shaped structure is viewed from within. Galileo Galilei first resolved the band of light into individual stars with his telescope in 1610, until the early 1920s, most astronomers thought that the Milky Way contained all the stars in the Universe. Following the 1920 Great Debate between the astronomers Harlow Shapley and Heber Curtis, observations by Edwin Hubble showed that the Milky Way is just one of many galaxies, the Milky Way is a barred spiral galaxy with a diameter between 100,000 light-years and 180,000 light-years. The Milky Way is estimated to contain 100–400 billion stars, there are probably at least 100 billion planets in the Milky Way. The Solar System is located within the disk, about 26,000 light-years from the Galactic Center, on the edge of one of the spiral-shaped concentrations of gas. The stars in the inner ≈10,000 light-years form a bulge, the very center is marked by an intense radio source, named Sagittarius A*, which is likely to be a supermassive black hole. Stars and gases at a range of distances from the Galactic Center orbit at approximately 220 kilometers per second. The constant rotation speed contradicts the laws of Keplerian dynamics and suggests much of the mass of the Milky Way does not emit or absorb electromagnetic radiation. This mass has been termed dark matter, the rotational period is about 240 million years at the position of the Sun. The Milky Way as a whole is moving at a velocity of approximately 600 km per second with respect to frames of reference. The oldest stars in the Milky Way are nearly as old as the Universe itself, the Milky Way has several satellite galaxies and is part of the Local Group of galaxies, which is a component of the Virgo Supercluster, which is itself a component of the Laniakea Supercluster. The Milky Way can be seen as a band of white light some 30 degrees wide arcing across the sky. Dark regions within the band, such as the Great Rift, the area of the sky obscured by the Milky Way is called the Zone of Avoidance. The Milky Way has a low surface brightness. Its visibility can be reduced by background light such as light pollution or stray light from the Moon. The sky needs to be darker than about 20.2 magnitude per square arcsecond in order for the Milky Way to be seen and it should be visible when the limiting magnitude is approximately +5.1 or better and shows a great deal of detail at +6.1
36.
Celestial equator
–
The celestial equator is a great circle on the imaginary celestial sphere, in the same plane as the Earths equator. In other words, it is a projection of the terrestrial equator out into space, as a result of the Earths axial tilt, the celestial equator is inclined by 23. 4° with respect to the ecliptic plane. An observer standing on the Earths equator visualizes the celestial equator as a semicircle passing directly overhead through the zenith, as the observer moves north, the celestial equator tilts towards the opposite horizon. Celestial objects near the equator are visible worldwide, but they culminate the highest in the sky in the tropics. The celestial equator currently passes through these constellations, Celestial bodies other than Earth also have similarly defined celestial equators, Celestial pole Celestial sphere Declination Equatorial coordinate system
37.
Tropical year
–
Because of the precession of the equinoxes, the seasonal cycle does not remain exactly synchronized with the position of the Earth in its orbit around the Sun. As a consequence, the year is about 20 minutes shorter than the time it takes Earth to complete one full orbit around the Sun as measured with respect to the fixed stars. Since antiquity, astronomers have progressively refined the definition of the tropical year, the entry for year, tropical in the Astronomical Almanac Online Glossary 2015 states, the period of time for the ecliptic longitude of the Sun to increase 360 degrees. The mean tropical year is approximately 365 days,5 hours,48 minutes,45 seconds, an equivalent, more descriptive, definition is The natural basis for computing passing tropical years is the mean longitude of the Sun reckoned from the precessionally moving equinox. Whenever the longitude reaches a multiple of 360 degrees the mean Sun crosses the vernal equinox, the mean tropical year in 2000 was 365.24219 ephemeris days, each ephemeris day lasting 86,400 SI seconds. This is 365.24217 mean solar days, the word tropical comes from the Greek tropikos meaning turn. Thus, the tropics of Cancer and Capricorn mark the north and south latitudes where the Sun can appear directly overhead. Because of this connection between the tropics and the cycle of the apparent position of the Sun, the word tropical also lent its name to the tropical year. The early Chinese, Hindus, Greeks, and others made approximate measures of the tropical year, in the 2nd century BC Hipparchus measured the time required for the Sun to travel from an equinox to the same equinox again. He reckoned the length of the year to be 1/300 of a day less than 365.25 days, Hipparchus used this method because he was better able to detect the time of the equinoxes, compared to that of the solstices. He reckoned the value as 1° per century, a value that was not improved upon until about 1000 years later, since this discovery a distinction has been made between the tropical year and the sidereal year. During the Middle Ages and Renaissance a number of progressively better tables were published that allowed computation of the positions of the Sun, Moon, an important application of these tables was the reform of the calendar. The length of the year was given as 365 solar days 5 hours 49 minutes 16 seconds. This length was used in devising the Gregorian calendar of 1582, in the 16th century Copernicus put forward a heliocentric cosmology. This was actually less accurate than the value of the Alfonsine Tables. Major advances in the 17th century were made by Johannes Kepler, in 1609 and 1619 Kepler published his three laws of planetary motion. In 1627, Kepler used the observations of Tycho Brahe and Waltherus to produce the most accurate tables up to that time and he evaluated the mean tropical year as 365 solar days,5 hours,48 minutes,45 seconds. Newtons three laws of dynamics and theory of gravity were published in his Philosophiæ Naturalis Principia Mathematica in 1687 and these effects did not begin to be understood until Newtons time
38.
Astrolabe
–
An astrolabe is an elaborate inclinometer, historically used by astronomers and navigators, to measure the inclined position in the sky of a celestial body, day or night. It can thus be used to identify stars or planets, to determine local latitude given local time and vice versa, to survey and it was used in classical antiquity, the Islamic Golden Age, the European Middle Ages and the Renaissance for all these purposes. While the astrolabe is effective for determining latitude on land or calm seas, the mariners astrolabe was developed to solve that problem. OED gives the translation star-taker for the English word astrolabe and traces it, through medieval Latin, to the Greek word astrolabos from astron star, in the medieval Islamic world the word asturlab was given various etymologies. In Arabic texts, the word is translated as akhdh al-kawakib which corresponds to an interpretation of the Greek word, al-Biruni quotes and criticizes the medieval scientist Hamzah al-Isfahani who had stated, asturlab is an arabization of this Persian phrase. In medieval Islamic sources, there is also a fictional and popular etymology of the words as lines of lab, in this popular etymology, Lab is a certain son of Idris. This etymology is mentioned by a 10th-century scientist named al-Qummi but rejected by al-Khwarizmi, Lab in Arabic also means sun and black stony places. An early astrolabe was invented in the Hellenistic world by Apollonius of Perga, a marriage of the planisphere and dioptra, the astrolabe was effectively an analog calculator capable of working out several different kinds of problems in spherical astronomy. Theon of Alexandria wrote a treatise on the astrolabe. Some historians attribute the invention to Hypatia, the daughter of Theon of Alexandria, noting that Synesius. Astrolabes continued in use in the Greek-speaking world throughout the Byzantine period, about 550 AD the Christian philosopher John Philoponus wrote a treatise on the astrolabe in Greek, which is the earliest extant Greek treatise on the instrument. In addition, Severus Sebokht, a bishop who lived in Mesopotamia, Astrolabes were further developed in the medieval Islamic world, where Muslim astronomers introduced angular scales to the astrolabe, adding circles indicating azimuths on the horizon. It was widely used throughout the Muslim world, chiefly as an aid to navigation and as a way of finding the Qibla, the first person credited with building the astrolabe in the Islamic world is reportedly the 8th-century mathematician Muhammad al-Fazari. The mathematical background was established by the Muslim astronomer Albatenius in his treatise Kitab az-Zij, the earliest surviving dated astrolabe is dated AH315. In the Islamic world, astrolabes were used to find the times of sunrise and the rising of fixed stars, to help schedule morning prayers. In the 10th century, al-Sufi first described over 1,000 different uses of an astrolabe, in areas as diverse as astronomy, astrology, navigation, surveying, timekeeping, prayer, Salat, Qibla, etc. The spherical astrolabe, a variation of both the astrolabe and the sphere, was invented during the Middle Ages by astronomers and inventors in the Islamic world. The earliest description of the spherical astrolabe dates back to Al-Nayrizi, in the 12th century, Sharaf al-Dīn al-Tūsī invented the linear astrolabe, sometimes called the staff of al-Tusi, which was a simple wooden rod with graduated markings but without sights
39.
Astronomy in the medieval Islamic world
–
Islamic astronomy comprises the astronomical developments made in the Islamic world, particularly during the Islamic Golden Age, and mostly written in the Arabic language. These developments mostly took place in the Middle East, Central Asia, Al-Andalus, and North Africa and these included Greek, Sassanid, and Indian works in particular, which were translated and built upon. Islamic astronomy also had an influence on Chinese astronomy and Malian astronomy, a significant number of stars in the sky, such as Aldebaran, Altair and Deneb, and astronomical terms such as alidade, azimuth, and nadir, are still referred to by their Arabic names. A large corpus of literature from Islamic astronomy remains today, numbering approximately 10,000 manuscripts scattered throughout the world, even so, a reasonably accurate picture of Islamic activity in the field of astronomy can be reconstructed. These observations were based on the rising and setting of stars. Anwa continued to be developed after Islamization by the Arabs, where Islamic astronomers added mathematical methods to their empirical observations, according to David King, after the rise of Islam, the religious obligation to determine the qibla and prayer times inspired more progress in astronomy for centuries. The first astronomical texts that were translated into Arabic were of Indian and Persian origin, another text translated was the Zij al-Shah, a collection of astronomical tables compiled in Sasanid Persia over two centuries. Fragments of texts during this period indicate that Arabs adopted the function in place of the chords of arc used in Greek trigonometry. The House of Wisdom was an established in Baghdad under Abbasid caliph Al-Mamun in the early 9th century. From this time, independent investigation into the Ptolemaic system became possible, Astronomical research was greatly supported by the Abbasid caliph al-Mamun through The House of Wisdom. Baghdad and Damascus became the centers of such activity, the caliphs not only supported this work financially, but endowed the work with formal prestige. The first major Muslim work of astronomy was Zij al-Sindh by al-Khwarizmi in 830, the work contains tables for the movements of the sun, the moon and the five planets known at the time. The work is significant as it introduced Ptolemaic concepts into Islamic sciences and this work also marks the turning point in Islamic astronomy. Hitherto, Muslim astronomers had adopted a primarily research approach to the field, translating works of others, al-Khwarizmis work marked the beginning of nontraditional methods of study and calculations. In 850, al-Farghani wrote Kitab fi Jawani, the book primarily gave a summary of Ptolemic cosmography. However, it also corrected Ptolemy based on findings of earlier Arab astronomers, al-Farghani gave revised values for the obliquity of the ecliptic, the precessional movement of the apogees of the sun and the moon, and the circumference of the earth. The book was circulated through the Muslim world, and even translated into Latin. The period when a distinctive Islamic system of astronomy flourished, the period began as the Muslim astronomers began questioning the framework of the Ptolemaic system of astronomy
40.
Astrology in medieval Islam
–
The science dealing with such influences was termed astrology, a discipline contained within the field of astronomy. Throughout the medieval period the practical application of astrology was subject to deep philosophical debate by Muslim religious scholars, Medieval Islamic astrology and astronomy continued Hellenistic and Roman era traditions based on Ptolemys Almagest. During this time knowledge of astronomy was greatly increased, and the astrolabe was invented by Al Fazari, many modern star names are derived from their Arabic and Persian names. Its important to note even the word star is Persian word often used as first name for girls pronounced in Persian Setareh. Albumasur or Abu Mashar was one of the most influential Islamic astrologers and his treatise Introductorium in Astronomiam spoke of how only by observing the great diversity of planetary motions can we comprehend the unnumbered varieties of change in this world. Persians also combined the disciplines of medicine and astrology by linking the properties of herbs with specific zodiac signs. Mars, for instance, was considered hot and dry and so ruled plants with a hot or pungent taste, like hellebore and these beliefs were adopted by European herbalists like Culpeper right up until the development of modern medicine. The Persians also developed a system, by which the difference between the ascendant and each planet of the zodiac was calculated and this new position then became a part of some kind. For example, the part of fortune is found by taking the difference between the sun and the ascendant and adding it to the moon. If the part thus calculated was in the 10th House in Libra, for instance, the calendar introduced by Omar Khayyám Neyshabouri, based on the classical zodiac, remains in effect in Afghanistan and Iran as the official Persian calendar. Another notable Persian astrologer and astronomer was Qutb al-Din al Shirazi born in Iran, al-Shirazi was also the first person to give the correct scientific explanation for the formation of a rainbow. Ulugh Beyg was a fifteenth-century Timurid Sultan and also a mathematician and he built an observatory in 1428 and produced the first original star map since Ptolemy, which corrected the position of many stars and included many new ones. Some of the principles of astrology were refuted by several medieval Islamic astronomers such as Al-Farabi, Ibn al-Haytham, Avicenna, Abu Rayhan al-Biruni and their reasons for refuting astrology were often due to both scientific and religious reasons. However these refutations mainly concerned the judicial branches of astrology rather than the principles of it. For example, Avicennas refutation of astrology revealed support for its overarching principles and he stated that it was true that each planet had some influence on the earth, but his argument was the difficulty of astrologers being able to determine the exact effect of it. In essence, Avicenna did not refute astrology, but denied man’s limited capacity to be able to know the effects of the stars on the sublunar matter. With that, he did not refute the essential dogma of astrology, why is it that you have given an influence to al-Ras and al-Dhanab, which are two imaginary points. According to jurists, the study of astronomy is lawful, as it is useful in predicting the beginning of months and seasons, determining the direction of salat, and navigation
41.
Mariner's astrolabe
–
Not an astrolabe proper, the mariners astrolabe was rather a graduated circle with an alidade used to measure vertical angles. They were designed to allow for their use on boats in rough water and/or in heavy winds, in the sixteenth century, the instrument was also called a ring. The Corpus Christi Museum of Science and History in Texas, United States, contains the worlds oldest mariners astrolabe with a date of 1554. Many dates can be found for the appearance of the first mariners astrolabes, the earliest date,1295, is offered by the Majorcan astronomer Ramon Llull. In any event, the instrument was known by the end of the 15th century. Nevertheless, the creation and perfecting of the astrolabe is attributed to Portuguese navigators during the beginning of Portuguese discoveries. The mariners astrolabe would have replaced or complemented instruments such as the staff or quadrant as a navigators instrument. The mariners astrolabe was used until the middle or, at the latest and it was replaced by more accurate and easier-to-use instruments such as the Davis quadrant and stratocaster. Although their heavy brass construction permits their longevity in marine environments, in 1979, only 35 were known to exist. While 65 were known by 1988, the biggest collection remains in museums in Portugal. Mariners astrolabes were made of brass, early sea astrolabes were made from sheets of brass. Due to their weight, they tended to perform poorly at sea. Heavier cast brass frames began to be made in the century and were considerably better. As the accuracy of the instrument is related to the radius of the divided circle, since the large plate form of the planispheric astrolabe makes it sensitive to the wind, the mariners astrolabe is made with a frame form. The openings in the frame allow wind to pass through, inducing less motion in the instrument, the essential function of the device was to measure angles. Thus the instrument featured a ring graduated in degrees, early instruments were only graduated for 90°, later instruments were graduated for the full 360° circle around the limb. The sole purpose of the spokes was to support the point for the alidade. This is clearly evident in the lower left instrument seen in the photograph above, the alidade was free to rotate about a pin through the centre of the instrument
42.
Surveying
–
Surveying or land surveying is the technique, profession, and science of determining the terrestrial or three-dimensional position of points and the distances and angles between them. A land surveying professional is called a land surveyor, Surveyors work with elements of geometry, trigonometry, regression analysis, physics, engineering, metrology, programming languages and the law. Surveying has been an element in the development of the environment since the beginning of recorded history. The planning and execution of most forms of construction require it and it is also used in transport, communications, mapping, and the definition of legal boundaries for land ownership. It is an important tool for research in other scientific disciplines. Basic surveyance has occurred since humans built the first large structures, the prehistoric monument at Stonehenge was set out by prehistoric surveyors using peg and rope geometry. In ancient Egypt, a rope stretcher would use simple geometry to re-establish boundaries after the floods of the Nile River. The almost perfect squareness and north-south orientation of the Great Pyramid of Giza, built c.2700 BC, the Groma instrument originated in Mesopotamia. The mathematician Liu Hui described ways of measuring distant objects in his work Haidao Suanjing or The Sea Island Mathematical Manual, the Romans recognized land surveyors as a profession. They established the basic measurements under which the Roman Empire was divided, Roman surveyors were known as Gromatici. In medieval Europe, beating the bounds maintained the boundaries of a village or parish and this was the practice of gathering a group of residents and walking around the parish or village to establish a communal memory of the boundaries. Young boys were included to ensure the memory lasted as long as possible, in England, William the Conqueror commissioned the Domesday Book in 1086. It recorded the names of all the owners, the area of land they owned, the quality of the land. It did not include maps showing exact locations, abel Foullon described a plane table in 1551, but it is thought that the instrument was in use earlier as his description is of a developed instrument. Gunters chain was introduced in 1620 by English mathematician Edmund Gunter and it enabled plots of land to be accurately surveyed and plotted for legal and commercial purposes. Leonard Digges described a Theodolite that measured horizontal angles in his book A geometric practice named Pantometria, joshua Habermel created a theodolite with a compass and tripod in 1576. Johnathon Sission was the first to incorporate a telescope on a theodolite in 1725, in the 18th century, modern techniques and instruments for surveying began to be used. Jesse Ramsden introduced the first precision theodolite in 1787 and it was an instrument for measuring angles in the horizontal and vertical planes
43.
Time
–
Time is the indefinite continued progress of existence and events that occur in apparently irreversible succession from the past through the present to the future. Time is often referred to as the dimension, along with the three spatial dimensions. Time has long been an important subject of study in religion, philosophy, and science, nevertheless, diverse fields such as business, industry, sports, the sciences, and the performing arts all incorporate some notion of time into their respective measuring systems. Two contrasting viewpoints on time divide prominent philosophers, one view is that time is part of the fundamental structure of the universe—a dimension independent of events, in which events occur in sequence. Isaac Newton subscribed to this realist view, and hence it is referred to as Newtonian time. This second view, in the tradition of Gottfried Leibniz and Immanuel Kant, holds that time is neither an event nor a thing, Time in physics is unambiguously operationally defined as what a clock reads. Time is one of the seven fundamental physical quantities in both the International System of Units and International System of Quantities, Time is used to define other quantities—such as velocity—so defining time in terms of such quantities would result in circularity of definition. The operational definition leaves aside the question there is something called time, apart from the counting activity just mentioned, that flows. Investigations of a single continuum called spacetime bring questions about space into questions about time, questions that have their roots in the works of early students of natural philosophy. Furthermore, it may be there is a subjective component to time. Temporal measurement has occupied scientists and technologists, and was a motivation in navigation. Periodic events and periodic motion have long served as standards for units of time, examples include the apparent motion of the sun across the sky, the phases of the moon, the swing of a pendulum, and the beat of a heart. Currently, the unit of time, the second, is defined by measuring the electronic transition frequency of caesium atoms. Time is also of significant social importance, having economic value as well as value, due to an awareness of the limited time in each day. In day-to-day life, the clock is consulted for periods less than a day whereas the calendar is consulted for periods longer than a day, increasingly, personal electronic devices display both calendars and clocks simultaneously. The number that marks the occurrence of an event as to hour or date is obtained by counting from a fiducial epoch—a central reference point. Artifacts from the Paleolithic suggest that the moon was used to time as early as 6,000 years ago. Lunar calendars were among the first to appear, either 12 or 13 lunar months, without intercalation to add days or months to some years, seasons quickly drift in a calendar based solely on twelve lunar months
44.
Qibla
–
The Qibla, also transliterated as Qiblah, Qibleh, Kiblah, Kıble or Kibla, is the direction that should be faced when a Muslim prays during salah prayers. It is fixed as the direction of the Kaaba in Mecca, most mosques contain a wall niche, known as mihrab, that indicates the Qiblah. Most multifaith prayer rooms will also contain a Qibla, although usually less standardized in appearance than one would find within a mosque, Muslims all praying towards the same point is traditionally considered to symbolize the unity of the Ummah, or all Muslims worldwide, under Sharia. The Qiblah has importance beyond salaat and plays a part in various ceremonies, the head of an animal that is slaughtered using halal methods is usually aligned with the Qiblah. After death, Muslims are usually buried with the body at angles to the Qibla. Thus, archaeology can indicate an Islamic necropolis if no signs are present. According to the traditional Muslim view, the Qiblah originally faced the Noble Sanctuary in Jerusalem and this Qiblah was used for over 13 years, from 610 CE until 623 CE. Seventeen months after the Islamic prophet Muhammads 622 CE arrival in Medina – the date is given as 11 February 624 – the Qiblah became oriented towards the Kaaba in Mecca. According to traditional accounts from Muhammads companions, the change happened very suddenly during the prayer in Medina. Muhammad was leading the prayer when he received revelations from God instructing him to take the Kaaba as the Qiblah, there is also disagreement as to when the practice started and for how long it lasted. Some sources say the Jerusalem Qiblah was used for a period of sixteen and eighteen months. The Jewish custom of facing Jerusalem for prayer may have influenced the Muslim Qiblah, others surmise that the use of Jerusalem as the direction of prayer was to either induce the Jews of Medina to convert to Islam or to win over their hearts. When relations with the Jews soured, Muhammad changed the Qiblah towards Mecca, another reason given why the Qiblah was changed is that Jews viewed the use of Jerusalem as signalling the Muslims intention of joining their religion. It was changed to discredit this assumption, others state that it was changed because Muhammad was angered by that city or its people, and not because of his conflict with the Jews. In Medieval times, Muslims travelling abroad used an astrolabe to find the Qiblah, cheraman Juma Masjid is a mosque in the south Indian state of Kerala. Believed to be built in 7th century CE by Malik Bin Deenar, it is thought to be the oldest mosque in India, and it was constructed during the lifetime of Muhammad, and the bodies of some of his original followers are said to be buried there. Unlike other mosques in Kerala state, which face westwards, this mosque faces eastwards, from whencesoever Thou startest forth, turn Thy face in the direction of the sacred Mosque, that is indeed the truth from the Lord. And Allah is not unmindful of what ye do, such are the people of truth, the Allah-fearing
45.
Salah
–
Salah, called namāz in some languages, is one of the Five Pillars in the faith of Islam and an obligatory religious duty for every Muslim. It is a physical, mental, and spiritual act of worship that is observed five times every day at prescribed times, in this ritual, the worshiper starts standing, bows, prostrates themself, and concludes while sitting on the ground. During each posture, the worshiper recites or reads certain verses, phrases, the word salah is commonly translated as prayer but this definition might be confusing. Muslims use the words dua or supplication when referring to the definition of prayers which is reverent petitions made to God. Salah is preceded by ritual ablution, Salah consists of the repetition of a unit called a rakʿah consisting of prescribed actions and words. The number of obligatory rakaʿāt varies from two to four according to the time of day or other circumstances, prayer is obligatory for all Muslims except those who are prepubescent, are menstruating, or are experiencing bleeding in the 40 days after childbirth. Every movement in the salat is accompanied by the takbir except the standing between the ruku and sujud, and the ending which has a derivation of the Muslim greeting As-salamu alaykum, Salah is an Arabic word whose basic meaning is bowing, homage, worship, prayer. In its English usage, the reference of the word is almost always confined to the Muslim formal, Muslims themselves use several terms to refer to salah depending on their language or culture. In many parts of the world, including many non-Arab countries such as Indonesia, the other major term is the Persian word namāz, used by speakers of the Indo-Iranian languages, as well as Turkish, Russian, Chinese, Bosnian and Albanian. In North Caucasian languages, the term is lamaz in Chechen and this is a book, there is no doubt in it, a guidance for righteous. Those who believe in unseen and offer Salah and spend from what we have given to them, and those who believe in what We have revealed to thee and what We revealed before thee, and on hereafter they believe. They are on guidance from their lord and they are successful, and offer Salah and pay Zakah and bow along those who bow. Guard your Salah and middle Salah, and stand before God devoutly obedient, then if you fear on foot or riding, then when you become secure remember God as he has taught you that which you did not know previously. And offer Salah at the two ends of day and at the approach of night, indeed good deeds remove bad deeds, offer Salah at the decline of the day until the darkness of night, and Quran at dawn, indeed Quran at dawn ever is a witness. And at night pray Tahajjud an extra for thee, it is expected that your lord raise you to praised station. ) Say call God or call Merciful, by whomever you call, He has good names, and offer Salah and pay Zakah and obey Messenger so that you may receive mercy. And recite that is revealed to you as a book and offer Salah, indeed Salah prohibits immorality and wrongdoing, and remembrance of God is great, ) The chief purpose of salah is to act as a persons communication with and remembrance of God. By reciting The Opening, the first sura of the Quran, as required in daily worship, the worshiper can stand before God, thank and praise Him, under the Hanbali School of thought, a person who doesnt pray five times a day is an unbeliever
46.
Sufi Observing Competition
–
Sufi Observing Competition is an international competition and like Messier marathon, but more difficult with various subjects. Since 2006, Astronomical Society of Iran – Amateur Committee holds an international observing competition in the memory of Azophi, the first competition was held in 2006 in the north of Semnan Province and the 2nd SUFI observing competition was held in summer of 2008 in Ladiz near Zahedan. More than 100 observers from Iran and Iraq participated in this event, third Sufi Competition was held in Pasargadae, Fars province of Iran, at the enclosure of the historical tomb of Cyrus the Great on 17–20 August 2009. More than 120 amateur astronomers participated in competition which held in 2 class of individuals. Closing ceremony of 3rd Sufi Competition was held in Persepolis historical site splendidly which is in the list of UNESCO world heritage site. Babak Amin Tafreshi, Pouria Nazemi, Kazem Kookaram and Mohammad H. Almasi are Iranian amateur astronomers who designed and manage this competition in their country until today
47.
Semnan, Iran
–
Semnan is the capital city of Semnan Province, Iran. Its population was 153,680 people and 36,298 families as of the 2011 census, Semnan is located 216 kilometers east of Tehran in north central Iran. It is home to Semnani languages and is known as Seman locally, the city offer various recreational activities, historical and religious sites, festivals, gardens and parks, colleges and universities, and Semnani culture. The city serves as the cultural and political capital of the Semnan Province, the citys main souvenirs are daffodil flowers, Shirmal pastry, Kolüçe cookies, kilim rugs, and shortbread. There are several theories which seek to explain the origin of the name Semnan, according to the first theory, Semnan was an ancient pre-zoroastrian city in which the locals practiced idol-worshipping. Their religion was called samīna, hence the name Semnan, according to the second theory, Semnan was an ancient civil establishment by the Scythians, an Iranian people who named their settlement Sakanān. According to the theory, Semnan was established by the mythical character Tahmuras. The fifth known theory simply states that the ancient regional language was known as Sa ma nān, and that the city of these people took on the name of their language. According to the sixth known theory, the name Semnan comes from the phrase sa ma nān and this phrase traces back to the Semnani womens tradition of cooking three months worth of bread in one day. The city of Semnan is situated at 1,138 metres above sea level just south of the foothills of the Alborz Mountains, unlike modern day Tehran, the city of Semnan is relatively flat. The city of Semnan enjoys the traditional four seasons of spring, summer, winter, during some winters, moisture-abundant blizzards make their way down from the Alborz mountains from the north of the city and dump several centimeters of snow in a single twenty-four-hour period. These blizzards force the closure of the airport, schools, small streets, according to Iranian Meteorology reports, Semnan experiences around 48 days in which the temperature falls below freezing each year. Spring is characterized by mild to warm day temperatures and cold to cool nights along with a reduction in precipitation as the season transitions into Summer, Summer is often characterized by hot daily temperatures and warm nights. Summer months remain dry with trace amounts of rainfall, occasionally, moisture from the Caspian Sea files through the Alborz mountains, the updraft of warm and moist air up the high mountain sides produces partly cloudy skies dominated by cumulus clouds. With the right amounts of heat and moisture, thunderstorms may develop during the afternoon, though the amount of precipitation is light, these thunderstorms often produce strong and gusty winds with frequent lightning strikes. Autumn is also a season in which the daily temperatures range from hot to cool along with cool nights. The city of Semnan has historically been one of the fourteen civil establishments of the ancient, Semnan remained an important city throughout the era of the Persian Achaemenid Empire. The beginning of the era of the city arrived with the rise of the Arsacid Dynasty of Parthia
48.
Taurus (constellation)
–
Taurus is one of the constellations of the zodiac, which means it is crossed by the plane of the ecliptic. Taurus is a large and prominent constellation in the northern hemispheres winter sky and it is one of the oldest constellations, dating back to at least the Early Bronze Age when it marked the location of the Sun during the spring equinox. Its importance to the agricultural calendar influenced various bull figures in the mythologies of Ancient Sumer, Akkad, Assyria, Babylon, Egypt, Greece, a number of features exist that are of interest to astronomers. Taurus hosts two of the nearest open clusters to Earth, the Pleiades and the Hyades, both of which are visible to the naked eye, at first magnitude, the red giant Aldebaran is the brightest star in the constellation. In the northwest part of Taurus is the supernova remnant Messier 1, one of the closest regions of active star formation, the Taurus-Auriga complex, crosses into the northern part of the constellation. The variable star T Tauri is the prototype of a class of pre-main-sequence stars, in September and October, Taurus is visible in the evening along the eastern horizon. The most favorable time to observe Taurus in the sky is during the months of December. By March and April, the constellation will appear to the west during the evening twilight and this constellation forms part of the zodiac, and hence is intersected by the ecliptic. This circle across the sphere forms the apparent path of the Sun as the Earth completes its annual orbit. As the orbital plane of the Moon and the planets lie near the ecliptic, the galactic plane of the Milky Way intersects the northeast corner of the constellation and the galactic anticenter is located near the border between Taurus and Auriga. Taurus is the only constellation crossed by all three of the equator, celestial equator, and ecliptic. A ring-like galactic structure known as the Goulds Belt passes through the Taurus constellation, the recommended three-letter abbreviation for the constellation, as adopted by the International Astronomical Union in 1922, is Tau. The official constellation boundaries, as set by Eugène Delporte in 1930, are defined by a polygon of 26 segments. In the equatorial coordinate system, the right ascension coordinates of these borders lie between 03h 23. 4m and 05h 53. 3m, while the coordinates are between 31. 10° and −1. 35°. Because a small part of the lies to the south of the celestial equator. During November, the Taurid meteor shower appears to radiate from the direction of this constellation. The Beta Taurid meteor shower occurs during the months of June and July in the daytime, between 18 and 29 October, both the Northern Taurids and the Southern Taurids are active, though the latter stream is stronger. However, between November 1 and 10, the two streams equalize, the brightest member of this constellation is Aldebaran, an orange-hued, spectral class K5 III giant star
