Sun vs York

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The Sun is the star at the center of the Solar System. It is a nearly perfect sphere of hot plasma, heated to incandescence by nuclear fusion reactions in its core, radiating the energy mainly as light and infrared radiation. It is by far the most important source of energy for life on Earth. Its diameter is about 1.39 million kilometres (864,000 miles), or 109 times that of Earth, and its mass is about 330,000 times that of Earth. It accounts for about 99.86% of the total mass of the Solar System. Roughly three quarters of the Sun's mass consists of hydrogen (~73%); the rest is mostly helium (~25%), with much smaller quantities of heavier elements, including oxygen, carbon, neon, and iron.The Sun is a G-type main-sequence star (G2V) based on its spectral class. As such, it is informally and not completely accurately referred to as a yellow dwarf (its light is closer to white than yellow). It formed approximately 4.6 billion years ago from the gravitational collapse of matter within a region of a large molecular cloud. Most of this matter gathered in the center, whereas the rest flattened into an orbiting disk that became the Solar System. The central mass became so hot and dense that it eventually initiated nuclear fusion in its core. It is thought that almost all stars form by this process.

In its core the Sun currently fuses about 600 million tons of hydrogen into helium every second, converting 4 million tons of matter into energy every second as a result. This energy, which can take between 10,000 and 170,000 years to escape the core, is the source of the Sun's light and heat. When hydrogen fusion in its core has diminished to the point at which the Sun is no longer in hydrostatic equilibrium, its core will undergo a marked increase in density and temperature while its outer layers expand, eventually transforming the Sun into a red giant. It is calculated that the Sun will become sufficiently large to engulf the current orbits of Mercury and Venus, and render Earth uninhabitable – but not for about five billion years. After this, it will shed its outer layers and become a dense type of cooling star known as a white dwarf, and no longer produce energy by fusion, but still glow and give off heat from its previous fusion. The enormous effect of the Sun on Earth has been recognized since prehistoric times. The Sun has been regarded by some cultures as a deity. The synodic rotation of Earth and its orbit around the Sun are the basis of solar calendars, one of which is the predominant calendar in use today.

Source: Wikipedia

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York is a cathedral city and unitary authority area at the confluence of the rivers Ouse and Foss in England. The city is the county town of the historic county of Yorkshire. York is the most populous district within the lieutenancy area of North Yorkshire and second largest built-up area. City of York Council is a unitary authority responsible for providing all local services and facilities throughout the city and rural areas beyond the old city boundaries. The unitary authority is in the Leeds city region along with most of the former West Riding of Yorkshire, apart from South Yorkshire (in the Sheffield city region) and Derbyshire. At the 2011 census, the borough population was 198,051 and the population of the city was 153,717. The city is known for its famous historical landmarks such as York Minster and the city walls, as well as a variety of cultural and sporting activities, which makes it a popular tourist destination in England. It is about 25 miles (40 km) north-east of Leeds and 34 miles (55 km) north-west of Kingston upon Hull. The city was founded by the Romans as Eboracum in 71 AD. It became the capital of the Roman province of Britannia Inferior, and later of the kingdoms of Deira, Northumbria and Jórvík.

In the Middle Ages, York grew as a major wool trading centre and became the capital of the northern ecclesiastical province of the Church of England, a role it has retained. In the 19th century, York became a major hub of the railway network and a confectionery manufacturing centre, a status it maintained well into the 20th century. During the Second World War, York was bombed as part of the Baedeker Blitz. Although less affected by bombing than other northern cities, several historic buildings were gutted and restoration efforts continued into the 1960s.The economy of York is dominated by services. The University of York and National Health Service are major employers, whilst tourism has become an important element of the local economy. In 2016, York became sister cities with the Chinese city of Nanjing, as per an agreement signed by the Lord Mayor of York, focusing on building links in tourism, education, science, technology and culture. Today, the city is a popular tourist attraction, especially for international visitors from America, Germany, France and China. In 2017, York became UK's first human rights city, which formalised the city's aim to use human rights in decision making.

Source: Wikipedia