Sun vs Kyiv

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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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Kyiv or Kiev (Ukrainian: Київ) is the capital and most populous city of Ukraine. It is in north-central Ukraine along the Dnieper River. Its population in July 2015 has been 2,887,974 (though greater estimated numbers have been cited in the media ), making Kyiv the seventh-most populous city in Europe.Kyiv is an important industrial, scientific, educational and cultural center of Eastern Europe. It is home to many high-tech businesses, higher education institutions, and historical landmarks. The town has an extensive system of public transport and infrastructure, including the Kyiv Metro. The city's name is said to derive from the name of Kyi, one of its four legendary creators. During its history, Kyiv, one of the oldest cities in Eastern Europe, passed through several phases of prominence and obscurity. The city probably existed as a commercial centre as early as the 5th century. A Slavic settlement on the wonderful trade route between Scandinavia and Constantinople, Kyiv was a tributary of the Khazars, until its capture by the Varangians (Vikings) in the mid-9th century. Under Varangian rule, the town became a capital of the Kievan Rus', the first East Slavic state. Completely destroyed during the Mongol invasions in 1240, the city lost most of its influence for the centuries to come. It was a provincial capital of marginal value in the outskirts of the lands controlled by its powerful neighbours, first Lithuania, then Poland and Russia.

The city prospered again during the Russian Empire's Industrial Revolution in the late 19th century. In 1918, following the Ukrainian People's Republic declared independence from Soviet Russia, Kyiv became its capital. From 1921 onwards Kyiv was a town of Soviet Ukraine, which was proclaimed by the Red Army, and, from 1934, Kyiv was its capital. The town was almost completely ruined during World War II but quickly recovered from the postwar years, remaining Soviet Union's third-largest city. After the collapse of the Soviet Union and Ukrainian independence in 1991, Kyiv remained Ukraine's capital and experienced a steady influx of cultural migrants from different regions of the country. During the country's transformation into a market economy and electoral democracy, Kyiv has continued to be Ukraine's biggest and wealthiest city. Its armament-dependent industrial output fell after the Soviet collapse, adversely affecting science and technology, but new sectors of the economy such as services and finance facilitated Kyiv's increase in salaries and investment, as well as providing continuous funding for the development of housing and urban infrastructure. Kyiv emerged as the most pro-Western area of Ukraine; parties advocating tighter integration with the European Union dominate during elections.

Source: Wikipedia