The United Kingdom the United Kingdom of Great Britain and Northern Ireland, sometimes referred to as Britain, is a sovereign country located off the north-western coast of the European mainland. The United Kingdom includes the island of Great Britain, the north-eastern part of the island of Ireland, many smaller islands. Northern Ireland is the only part of the United Kingdom that shares a land border with another sovereign state, the Republic of Ireland. Apart from this land border, the United Kingdom is surrounded by the Atlantic Ocean, with the North Sea to the east, the English Channel to the south and the Celtic Sea to the south-west, giving it the 12th-longest coastline in the world; the Irish Sea lies between Great Ireland. With an area of 242,500 square kilometres, the United Kingdom is the 78th-largest sovereign state in the world, it is the 22nd-most populous country, with an estimated 66.0 million inhabitants in 2017. The UK is constitutional monarchy; the current monarch is Queen Elizabeth II, who has reigned since 1952, making her the longest-serving current head of state.
The United Kingdom's capital and largest city is London, a global city and financial centre with an urban area population of 10.3 million. Other major urban areas in the UK include Greater Manchester, the West Midlands and West Yorkshire conurbations, Greater Glasgow and the Liverpool Built-up Area; the United Kingdom consists of four constituent countries: England, Scotland and Northern Ireland. Their capitals are London, Edinburgh and Belfast, respectively. Apart from England, the countries have their own devolved governments, each with varying powers, but such power is delegated by the Parliament of the United Kingdom, which may enact laws unilaterally altering or abolishing devolution; the nearby Isle of Man, Bailiwick of Guernsey and Bailiwick of Jersey are not part of the UK, being Crown dependencies with the British Government responsible for defence and international representation. The medieval conquest and subsequent annexation of Wales by the Kingdom of England, followed by the union between England and Scotland in 1707 to form the Kingdom of Great Britain, the union in 1801 of Great Britain with the Kingdom of Ireland created the United Kingdom of Great Britain and Ireland.
Five-sixths of Ireland seceded from the UK in 1922, leaving the present formulation of the United Kingdom of Great Britain and Northern Ireland. There are fourteen British Overseas Territories, the remnants of the British Empire which, at its height in the 1920s, encompassed a quarter of the world's land mass and was the largest empire in history. British influence can be observed in the language and political systems of many of its former colonies; the United Kingdom is a developed country and has the world's fifth-largest economy by nominal GDP and ninth-largest economy by purchasing power parity. It has a high-income economy and has a high Human Development Index rating, ranking 14th in the world, it was the world's first industrialised country and the world's foremost power during the 19th and early 20th centuries. The UK remains a great power, with considerable economic, military and political influence internationally, it is sixth in military expenditure in the world. It has been a permanent member of the United Nations Security Council since its first session in 1946.
It has been a leading member state of the European Union and its predecessor, the European Economic Community, since 1973. The United Kingdom is a member of the Commonwealth of Nations, the Council of Europe, the G7, the G20, NATO, the Organisation for Economic Co-operation and Development and the World Trade Organization; the 1707 Acts of Union declared that the kingdoms of England and Scotland were "United into One Kingdom by the Name of Great Britain". The term "United Kingdom" has been used as a description for the former kingdom of Great Britain, although its official name from 1707 to 1800 was "Great Britain"; the Acts of Union 1800 united the kingdom of Great Britain and the kingdom of Ireland in 1801, forming the United Kingdom of Great Britain and Ireland. Following the partition of Ireland and the independence of the Irish Free State in 1922, which left Northern Ireland as the only part of the island of Ireland within the United Kingdom, the name was changed to the "United Kingdom of Great Britain and Northern Ireland".
Although the United Kingdom is a sovereign country, Scotland and Northern Ireland are widely referred to as countries. The UK Prime Minister's website has used the phrase "countries within a country" to describe the United Kingdom; some statistical summaries, such as those for the twelve NUTS 1 regions of the United Kingdom refer to Scotland and Northern Ireland as "regions". Northern Ireland is referred to as a "province". With regard to Northern Ireland, the descriptive name used "can be controversial, with the choice revealing one's political preferences"; the term "Great Britain" conventionally refers to the island of Great Britain, or politically to England and Wales in combination. However, it is sometimes used as a loose synonym for the United Kingdom as a whole; the term "Britain" is used both as a synonym for Great Britain, as a synonym for the United Kingdom. Usage is mixed, with the BBC preferring to use Britain as shorthand only for Great Britain and the UK Government, while accepting that both terms refer to the United K
Asia is Earth's largest and most populous continent, located in the Eastern and Northern Hemispheres. It shares the continental landmass of Eurasia with the continent of Europe and the continental landmass of Afro-Eurasia with both Europe and Africa. Asia covers an area of 44,579,000 square kilometres, about 30% of Earth's total land area and 8.7% of the Earth's total surface area. The continent, which has long been home to the majority of the human population, was the site of many of the first civilizations. Asia is notable for not only its overall large size and population, but dense and large settlements, as well as vast populated regions, its 4.5 billion people constitute 60% of the world's population. In general terms, Asia is bounded on the east by the Pacific Ocean, on the south by the Indian Ocean, on the north by the Arctic Ocean; the border of Asia with Europe is a historical and cultural construct, as there is no clear physical and geographical separation between them. It has moved since its first conception in classical antiquity.
The division of Eurasia into two continents reflects East–West cultural and ethnic differences, some of which vary on a spectrum rather than with a sharp dividing line. The most accepted boundaries place Asia to the east of the Suez Canal separating it from Africa. China and India alternated in being the largest economies in the world from 1 to 1800 CE. China was a major economic power and attracted many to the east, for many the legendary wealth and prosperity of the ancient culture of India personified Asia, attracting European commerce and colonialism; the accidental discovery of a trans-Atlantic route from Europe to America by Columbus while in search for a route to India demonstrates this deep fascination. The Silk Road became the main east–west trading route in the Asian hinterlands while the Straits of Malacca stood as a major sea route. Asia has exhibited economic dynamism as well as robust population growth during the 20th century, but overall population growth has since fallen. Asia was the birthplace of most of the world's mainstream religions including Hinduism, Judaism, Buddhism, Taoism, Islam, Sikhism, as well as many other religions.
Given its size and diversity, the concept of Asia—a name dating back to classical antiquity—may have more to do with human geography than physical geography. Asia varies across and within its regions with regard to ethnic groups, environments, historical ties and government systems, it has a mix of many different climates ranging from the equatorial south via the hot desert in the Middle East, temperate areas in the east and the continental centre to vast subarctic and polar areas in Siberia. The boundary between Asia and Africa is the Red Sea, the Gulf of Suez, the Suez Canal; this makes Egypt a transcontinental country, with the Sinai peninsula in Asia and the remainder of the country in Africa. The border between Asia and Europe was defined by European academics; the Don River became unsatisfactory to northern Europeans when Peter the Great, king of the Tsardom of Russia, defeating rival claims of Sweden and the Ottoman Empire to the eastern lands, armed resistance by the tribes of Siberia, synthesized a new Russian Empire extending to the Ural Mountains and beyond, founded in 1721.
The major geographical theorist of the empire was a former Swedish prisoner-of-war, taken at the Battle of Poltava in 1709 and assigned to Tobolsk, where he associated with Peter's Siberian official, Vasily Tatishchev, was allowed freedom to conduct geographical and anthropological studies in preparation for a future book. In Sweden, five years after Peter's death, in 1730 Philip Johan von Strahlenberg published a new atlas proposing the Urals as the border of Asia. Tatishchev announced; the latter had suggested the Emba River as the lower boundary. Over the next century various proposals were made until the Ural River prevailed in the mid-19th century; the border had been moved perforce from the Black Sea to the Caspian Sea into which the Ural River projects. The border between the Black Sea and the Caspian is placed along the crest of the Caucasus Mountains, although it is sometimes placed further north; the border between Asia and the region of Oceania is placed somewhere in the Malay Archipelago.
The Maluku Islands in Indonesia are considered to lie on the border of southeast Asia, with New Guinea, to the east of the islands, being wholly part of Oceania. The terms Southeast Asia and Oceania, devised in the 19th century, have had several vastly different geographic meanings since their inception; the chief factor in determining which islands of the Malay Archipelago are Asian has been the location of the colonial possessions of the various empires there. Lewis and Wigen assert, "The narrowing of'Southeast Asia' to its present boundaries was thus a gradual process." Geographical Asia is a cultural artifact of European conceptions of the world, beginning with the Ancient Greeks, being imposed onto other cultures, an imprecise concept causing endemic contention about what it means. Asia does not correspond to the cultural borders of its various types of constituents. From the time of Herodotus a minority of geographers have rejected the three-continent system on the grounds that there is no substantial physical separation between
Akrotiri and Dhekelia
The Sovereign Base Areas of Akrotiri and Dhekelia is a British Overseas Territory on the island of Cyprus. The areas, which include British military bases and installations, as well as other land, were retained by the British under the 1960 treaty of independence, signed by the United Kingdom, Greece and representatives from the Greek and Turkish Cypriot communities, which granted independence to the Crown colony of Cyprus; the territory serves an important role as a station for signals intelligence and provides a vital strategic part of the United Kingdom communications gathering and monitoring network in the Mediterranean and the Middle East. The territory is composed of two Base Areas. One is Akrotiri, or the Western Sovereign Base Area, which includes two main bases at RAF Akrotiri and Episkopi, plus all of Akrotiri Village's district and parts of eleven other village districts; the other area is Dhekelia Cantonment, or the Eastern Sovereign Base Area, which includes a base at Ayios Nikolaos plus parts of twelve village districts.
The Sovereign Base Areas were created in 1960 by the London and Zurich Agreements, when Cyprus achieved independence from the British Empire. The United Kingdom desired to retain sovereignty over these areas, as this guaranteed the use of UK military bases on Cyprus, including RAF Akrotiri, a garrison of the British Army; the importance of the bases to the British is based on the strategic location of the island, at the eastern edge of the Mediterranean, close to the Suez Canal and the Middle East. In July and August 1961, there was a series of bomb-attacks against the pipeline carrying fresh water to the Dhekelia Sovereign Base Area The pipeline was breached by explosions twelve times. In 1974, following a military coup by the Cypriot National Guard attempting to achieve enosis, Turkey invaded the north of Cyprus, leading to the establishment of the internationally unrecognised Turkish Republic of Northern Cyprus; this did not affect the status of the bases. Greek Cypriots fleeing from the Turkish forces were permitted to travel through the Dhekelia Sovereign Base Area and were given humanitarian aid, with those from Achna setting up a new village, still in the Dhekelia Sovereign Base Area.
The Turkish advance halted when it reached the edge of the Dhekelia Sovereign Base Area to avoid military conflict with the United Kingdom. In the Akrotiri Sovereign Base Area a tented refugee camp was set up at "Happy Valley" to house Turkish Cypriots fleeing from Limassol and the villages surrounding the Area, until in 1975 they were flown out of RAF Akrotiri via Turkey to northern Cyprus; some Greek Cypriot refugees remain housed on land in the parts of Trachoni and Kolossi villages that fall within the Akrotiri Sovereign Base Area. In July 2001, protests were held at the bases by local Cypriots, unhappy with British plans to construct radio masts at the bases as part of an upgrade of British military communication posts around the world. Locals claimed the masts would endanger local lives and cause cancer, as well as have a negative impact on wildlife in the area; the British and Cypriot governments jointly commissioned health research from the University of Bristol and the Ministry of Health of the Republic of Cyprus, that research project reported in 2005 that there was no evidence of health problems being caused by electromagnetic fields from the antennas.
The Sovereign Base Areas Administration has carried out assessments and surveys into the effects on wildlife, which have fed into an "Akrotiri Peninsula Environmental Management Plan", published in September 2012. The United Kingdom has shown no intention of ceding the Sovereign Base Areas in their entirety to Cypriot control, although it has offered to cede 117 square kilometres of farmland as part of the rejected Annan Plan for Cyprus; as of 2010, around 3,000 troops of British Forces Cyprus are based at Dhekelia. Ayios Nikolaos Station, in the ESBA, is an ELINT listening station of the UKUSA Agreement intelligence network; the election of left-wing Demetris Christofias as Cypriot president in February 2008 prompted concern in the United Kingdom. Christofias pledged to remove all foreign military forces from the island as part of a future settlement of the Cyprus dispute, calling the British presence on the island a "colonial bloodstain". On 29 August 2013, during the Syrian civil war, some Cypriot and British media sources speculated that long-range ballistic missiles, fired from Syria in retaliation for proposed British involvement in military intervention against the Syrian government of Bashar al-Assad, could hit Cyprus, could deliver chemical weapons.
In some Cypriot media it was stated that the proposed interdiction of the Syrian civil war, utilising Akrotiri and Dhekelia, could recklessly endanger the Cypriot populations near to those bases. Two days earlier, on 27 August 2013, Cypriot foreign minister Ioannis Kasoulides had moved to calm Cypriot concerns, saying that the British bases were unlikely to play a major part in any intervention. In January 2010, a newspaper article appeared in the British press claiming that as a result of budgetary constraints arising from the Great Recession, the British Ministry of Defence drew up controversial plans to withdraw the United Kingdom's 3,000 stron
Tibet Autonomous Region
The Tibet Autonomous Region or Xizang Autonomous Region, called Tibet or Xizang for short, is a province-level autonomous region in southwest China. It was formally established in 1965 to replace the Tibet Area, an administrative division the People's Republic of China took over from the Republic of China about five years after the dismissal of the Kashag by the PRC following the 1959 Tibetan uprising, about 13 years after Tibet's incorporation into the PRC in 1951; the current borders of the Tibet Autonomous Region were established in the 18th century and include about half of ethno-cultural Tibet. The Tibet Autonomous Region is the second-largest province-level division of China by area, spanning over 1,200,000 km2, after Xinjiang, due to its harsh and rugged terrain, is the least densely populated provincial-level division of the PRC. There is a politically-charged historical debate on the exact nature of relations between Tibet and the Chinese Ming dynasty and whether the Ming Dynasty had sovereignty over Tibet after the Mongol conquest of Tibet and Yuan administrative rule in the 13th and 14th centuries.
Qing dynasty rule in Tibet began with their 1720 expedition to the country when they expelled the invading Dzungars, Tibet was first controlled by central government. From 1912 to 1950 Tibet was under de jure suzerainty of the Republic of China, the difficulties of establishing a new government in the aftermath of the Xinhai Revolution, the fractious Warlord Era, the Chinese Civil War, the overwhelming Japanese invasion and occupation before and during World War II left the Republic unable to exert any effective administration. Other parts of ethno-cultural Tibet had been under de jure administration of the Chinese dynastic government since the mid-18th century. In 1950, the People's Liberation Army marched into Tibet and defeated the Tibetan local army in a battle fought near the city of Chamdo. In 1951, the Tibetan representatives signed a 17-point agreement with the Central People's Government affirming China's sovereignty over Tibet and the incorporation of Tibet; the agreement was ratified in Lhasa a few months later.
Although the 17-point agreement had provided for an autonomous administration led by the Dalai Lama, a "Preparatory Committee for the Autonomous Region of Tibet" was established in 1955 to exclude the Dalai Lama's government and create a system of administration along Communist lines. Under threat of his life from Chinese forces the Dalai Lama fled to India in 1959 and renounced the 17-point agreement. Tibet Autonomous Region was established in 1965, thus making Tibet a provincial-level division of China; the Tibet Autonomous Region is located on the highest region on earth. In northern Tibet elevations reach an average of over 4,572 metres. Mount Everest is located on Tibet's border with Nepal. China's provincial-level areas of Xinjiang and Sichuan lie to the north and east of the Tibet AR. There is a short border with Yunnan province to the southeast; the PRC has border disputes with the Republic of India over the McMahon Line of Arunachal Pradesh, known to the Chinese as "South Tibet". The disputed territory of Aksai Chin is to the west, its boundary with that region is not defined.
Doklam in Sikkim is disputed with Bhutan and India. The other countries to the south are Myanmar and Nepal. Physically, the Tibet AR may be divided into two parts, the lakes region in the west and north-west, the river region, which spreads out on three sides of the former on the east and west. Both regions receive limited amounts of rainfall as they lie in the rain shadow of the Himalayas, however the region names are useful in contrasting their hydrological structures, in contrasting their different cultural uses, nomadic in the lake region and agricultural in the river region. On the south the Tibet AR is bounded by the Himalayas, on the north by a broad mountain system; the system at no point narrows to a single range. As a whole the system forms the watershed between rivers flowing to the Indian Ocean − the Indus and Salween and its tributaries − and the streams flowing into the undrained salt lakes to the north; the lake region extends from the Pangong Tso Lake in Ladakh, Lake Rakshastal, Yamdrok Lake and Lake Manasarovar near the source of the Indus River, to the sources of the Salween, the Mekong and the Yangtze.
Other lakes include Dagze Co, Pagsum Co. The lake region is a wind-swept Alpine grassland; this region is called the Chang Tang or'Northern Plateau' by the people of Tibet. It is some 1,100 km broad, covers an area about equal to that of France. Due to its great distance from the ocean it is arid and possesses no river outlet; the mountain ranges are spread out, disconnected, separated by flat valleys. The Tibet AR is dotted over with large and small lakes salt or alkaline, intersected by streams. Due to the presence of discontinuous permafrost over the Chang Tang, the soil is boggy and covered with tussocks of grass, thus resembling the Siberian tundra. Salt and fresh-water lakes are inter
China the People's Republic of China, is a country in East Asia and the world's most populous country, with a population of around 1.404 billion. Covering 9,600,000 square kilometers, it is the third- or fourth-largest country by total area. Governed by the Communist Party of China, the state exercises jurisdiction over 22 provinces, five autonomous regions, four direct-controlled municipalities, the special administrative regions of Hong Kong and Macau. China emerged as one of the world's earliest civilizations, in the fertile basin of the Yellow River in the North China Plain. For millennia, China's political system was based on hereditary monarchies, or dynasties, beginning with the semi-legendary Xia dynasty in 21st century BCE. Since China has expanded, re-unified numerous times. In the 3rd century BCE, the Qin established the first Chinese empire; the succeeding Han dynasty, which ruled from 206 BC until 220 AD, saw some of the most advanced technology at that time, including papermaking and the compass, along with agricultural and medical improvements.
The invention of gunpowder and movable type in the Tang dynasty and Northern Song completed the Four Great Inventions. Tang culture spread in Asia, as the new Silk Route brought traders to as far as Mesopotamia and Horn of Africa. Dynastic rule ended in 1912 with the Xinhai Revolution; the Chinese Civil War resulted in a division of territory in 1949, when the Communist Party of China established the People's Republic of China, a unitary one-party sovereign state on Mainland China, while the Kuomintang-led government retreated to the island of Taiwan. The political status of Taiwan remains disputed. Since the introduction of economic reforms in 1978, China's economy has been one of the world's fastest-growing with annual growth rates above 6 percent. According to the World Bank, China's GDP grew from $150 billion in 1978 to $12.24 trillion by 2017. Since 2010, China has been the world's second-largest economy by nominal GDP and since 2014, the largest economy in the world by purchasing power parity.
China is the world's largest exporter and second-largest importer of goods. China is a recognized nuclear weapons state and has the world's largest standing army and second-largest defense budget; the PRC is a permanent member of the United Nations Security Council as it replaced the ROC in 1971, as well as an active global partner of ASEAN Plus mechanism. China is a leading member of numerous formal and informal multilateral organizations, including the Shanghai Cooperation Organization, WTO, APEC, BRICS, the BCIM, the G20. In recent times, scholars have argued that it will soon be a world superpower, rivaling the United States; the word "China" has been used in English since the 16th century. It is not a word used by the Chinese themselves, it has been traced through Portuguese and Persian back to the Sanskrit word Cīna, used in ancient India."China" appears in Richard Eden's 1555 translation of the 1516 journal of the Portuguese explorer Duarte Barbosa. Barbosa's usage was derived from Persian Chīn, in turn derived from Sanskrit Cīna.
Cīna was first used including the Mahābhārata and the Laws of Manu. In 1655, Martino Martini suggested that the word China is derived from the name of the Qin dynasty. Although this derivation is still given in various sources, it is complicated by the fact that the Sanskrit word appears in pre-Qin literature; the word may have referred to a state such as Yelang. The meaning transferred to China as a whole; the origin of the Sanskrit word is still a matter of debate, according to the Oxford English Dictionary. The official name of the modern state is the "People's Republic of China"; the shorter form is "China" Zhōngguó, from zhōng and guó, a term which developed under the Western Zhou dynasty in reference to its royal demesne. It was applied to the area around Luoyi during the Eastern Zhou and to China's Central Plain before being used as an occasional synonym for the state under the Qing, it was used as a cultural concept to distinguish the Huaxia people from perceived "barbarians". The name Zhongguo is translated as "Middle Kingdom" in English.
Archaeological evidence suggests that early hominids inhabited China between 2.24 million and 250,000 years ago. The hominid fossils of Peking Man, a Homo erectus who used fire, were discovered in a cave at Zhoukoudian near Beijing; the fossilized teeth of Homo sapiens have been discovered in Fuyan Cave in Hunan. Chinese proto-writing existed in Jiahu around 7000 BCE, Damaidi around 6000 BCE, Dadiwan from 5800–5400 BCE, Banpo dating from the 5th millennium BCE; some scholars have suggested. According to Chinese tradition, the first dynasty was the Xia, which emerged around 2100 BCE; the dynasty was considered mythical by historians until scientific excavations found early Bronze Age sites at Erlitou, Henan in 1959. It remains unclear whether these sites are the remains of the Xia dynasty or of another culture from the same period; the succeeding Shang dynasty is the earliest to be confirmed by contemporary records. The Shang ruled the plain of the Yellow River in eastern China from the 17th to the 11th century BCE.
Their oracle bone script
An equator of a rotating spheroid is its zeroth circle of latitude. It is the imaginary line on the spheroid, equidistant from its poles, dividing it into northern and southern hemispheres. In other words, it is the intersection of the spheroid with the plane perpendicular to its axis of rotation and midway between its geographical poles. On Earth, the Equator is 21.3 % over land. Indonesia is the country straddling the greatest length of the equatorial line across both land and sea; the name is derived from medieval Latin word aequator, in the phrase circulus aequator diei et noctis, meaning ‘circle equalizing day and night’, from the Latin word aequare meaning ‘make equal’. The latitude of the Earth's equator is, by definition, 0° of arc; the Equator is one of the five notable circles of latitude on Earth. The Equator is the only line of latitude, a great circle — that is, one whose plane passes through the center of the globe; the plane of Earth's equator, when projected outwards to the celestial sphere, defines the celestial equator.
In the cycle of Earth's seasons, the equatorial plane runs through the Sun twice per year: on the equinoxes in March and September. To a person on Earth, the Sun appears to travel above the Equator at these times. Light rays from the Sun's center are perpendicular to Earth's surface at the point of solar noon on the Equator. Locations on the Equator experience the shortest sunrises and sunsets because the Sun's daily path is nearly perpendicular to the horizon for most of the year; the length of daylight is constant throughout the year. Earth bulges at the Equator. Sites near the Equator, such as the Guiana Space Centre in Kourou, French Guiana, are good locations for spaceports as they have a faster rotational speed than other latitudes. Since Earth rotates eastward, spacecraft must be launched eastward to take advantage of this Earth-boost of speed; the precise location of the Equator is not fixed. This effect must be accounted for in detailed geophysical measurements; the International Association of Geodesy and the International Astronomical Union have chosen to use an equatorial radius of 6,378.1366 kilometres.
This equatorial radius is in the 2003 and 2010 IERS Conventions. It is the equatorial radius used for the IERS 2003 ellipsoid. If it were circular, the length of the Equator would be 2π times the radius, namely 40,075.0142 kilometres. The GRS 80 as approved and adopted by the IUGG at its Canberra, Australia meeting of 1979 has an equatorial radius of 6,378.137 kilometres. The WGS 84, a standard for use in cartography and satellite navigation including GPS has an equatorial radius of 6,378.137 kilometres. For both GRS 80 and WGS 84, this results in a length for the Equator of 40,075.0167 km. The geographical mile is defined as one arc-minute of the Equator, so it has different values depending on which radius is assumed. For example, by WSG-84, the distance is 1,855.3248 metres, while by IAU-2000, it is 1,855.3257 metres. This is a difference of less than one millimetre over the total distance; the earth is modeled as a sphere flattened 0.336% along its axis. This makes the Equator 0.16% longer than a meridian.
The IUGG standard meridian is, to the nearest millimetre, 40,007.862917 kilometres, one arc-minute of, 1,852.216 metres, explaining the SI standardization of the nautical mile as 1,852 metres, more than 3 metres less than the geographical mile. The sea-level surface of the Earth is irregular, so the actual length of the Equator is not so easy to determine. Aviation Week and Space Technology on 9 October 1961 reported that measurements using the Transit IV-A satellite had shown the equatorial "diameter" from longitude 11° West to 169° East to be 1,000 feet greater than its "diameter" ninety degrees away; the Equator passes through the land of 11 countries. Starting at the Prime Meridian and heading eastwards, the Equator passes through: Despite its name, no part of Equatorial Guinea lies on the Equator. However, its island of Annobón is 155 km south of the Equator, the rest of the country lies to the north. Seasons result from the tilt of the Earth's axis compared to the plane of its revolution around the Sun.
Throughout the year the northern and southern hemispheres are alternately turned either toward or away from the sun depending on Earth's position in its orbit. The hemisphere turned toward the sun receives more sunlight and is in summer, while the other hemisphere receives less sun and is in winter. At the equinoxes, the Earth's axis
The United States of America known as the United States or America, is a country composed of 50 states, a federal district, five major self-governing territories, various possessions. At 3.8 million square miles, the United States is the world's third or fourth largest country by total area and is smaller than the entire continent of Europe's 3.9 million square miles. With a population of over 327 million people, the U. S. is the third most populous country. The capital is Washington, D. C. and the largest city by population is New York City. Forty-eight states and the capital's federal district are contiguous in North America between Canada and Mexico; the State of Alaska is in the northwest corner of North America, bordered by Canada to the east and across the Bering Strait from Russia to the west. The State of Hawaii is an archipelago in the mid-Pacific Ocean; the U. S. territories are scattered about the Pacific Ocean and the Caribbean Sea, stretching across nine official time zones. The diverse geography and wildlife of the United States make it one of the world's 17 megadiverse countries.
Paleo-Indians migrated from Siberia to the North American mainland at least 12,000 years ago. European colonization began in the 16th century; the United States emerged from the thirteen British colonies established along the East Coast. Numerous disputes between Great Britain and the colonies following the French and Indian War led to the American Revolution, which began in 1775, the subsequent Declaration of Independence in 1776; the war ended in 1783 with the United States becoming the first country to gain independence from a European power. The current constitution was adopted in 1788, with the first ten amendments, collectively named the Bill of Rights, being ratified in 1791 to guarantee many fundamental civil liberties; the United States embarked on a vigorous expansion across North America throughout the 19th century, acquiring new territories, displacing Native American tribes, admitting new states until it spanned the continent by 1848. During the second half of the 19th century, the Civil War led to the abolition of slavery.
By the end of the century, the United States had extended into the Pacific Ocean, its economy, driven in large part by the Industrial Revolution, began to soar. The Spanish–American War and World War I confirmed the country's status as a global military power; the United States emerged from World War II as a global superpower, the first country to develop nuclear weapons, the only country to use them in warfare, a permanent member of the United Nations Security Council. Sweeping civil rights legislation, notably the Civil Rights Act of 1964, the Voting Rights Act of 1965 and the Fair Housing Act of 1968, outlawed discrimination based on race or color. During the Cold War, the United States and the Soviet Union competed in the Space Race, culminating with the 1969 U. S. Moon landing; the end of the Cold War and the collapse of the Soviet Union in 1991 left the United States as the world's sole superpower. The United States is the world's oldest surviving federation, it is a representative democracy.
The United States is a founding member of the United Nations, World Bank, International Monetary Fund, Organization of American States, other international organizations. The United States is a developed country, with the world's largest economy by nominal GDP and second-largest economy by PPP, accounting for a quarter of global GDP; the U. S. economy is post-industrial, characterized by the dominance of services and knowledge-based activities, although the manufacturing sector remains the second-largest in the world. The United States is the world's largest importer and the second largest exporter of goods, by value. Although its population is only 4.3% of the world total, the U. S. holds 31% of the total wealth in the world, the largest share of global wealth concentrated in a single country. Despite wide income and wealth disparities, the United States continues to rank high in measures of socioeconomic performance, including average wage, human development, per capita GDP, worker productivity.
The United States is the foremost military power in the world, making up a third of global military spending, is a leading political and scientific force internationally. In 1507, the German cartographer Martin Waldseemüller produced a world map on which he named the lands of the Western Hemisphere America in honor of the Italian explorer and cartographer Amerigo Vespucci; the first documentary evidence of the phrase "United States of America" is from a letter dated January 2, 1776, written by Stephen Moylan, Esq. to George Washington's aide-de-camp and Muster-Master General of the Continental Army, Lt. Col. Joseph Reed. Moylan expressed his wish to go "with full and ample powers from the United States of America to Spain" to seek assistance in the revolutionary war effort; the first known publication of the phrase "United States of America" was in an anonymous essay in The Virginia Gazette newspaper in Williamsburg, Virginia, on April 6, 1776. The second draft of the Articles of Confederation, prepared by John Dickinson and completed by June 17, 1776, at the latest, declared "The name of this Confederation shall be the'United States of America'".
The final version of the Articles sent to the states for ratification in late 1777 contains the sentence "The Stile of this Confederacy shall be'The United States of America'". In June 1776, Thomas Jefferson wrote the phrase "UNITED STATES OF AMERICA" in all capitalized letters in the headline of his "original Rough draught" of the Declaration of Independence; this draft of the document did not surface unti