Sun vs Bratislava

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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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Bratislava (, also US: , Slovak: [ˈbracislaʋa] (listen); Hungarian: Pozsony; German: Pressburg, formerly Preßburg [ˈprɛsbʊrk] (listen)) is the capital and largest city of Slovakia. Officially, the population of the city is about 430,000; however, it is estimated to be more than 660,000 - approximately 150% of the official figures. It is one of the smaller capitals of Europe but still the country's largest city. Bratislava is in southwestern Slovakia, occupying both banks of the River Danube and the left bank of the River Morava. Bordering Austria and Hungary, it is the only national capital that borders two sovereign states.The city's history has been influenced by people of many nations and religions, including Austrians, Bulgarians, Croats, Czechs, Germans, Hungarians, Jews, Serbs and Slovaks. It was the coronation site and legislative center and capital of the Kingdom of Hungary from 1536 to 1783, eleven Hungarian kings and eight queens were crowned in St.

Martin's Cathedral, and most Hungarian parliament assemblies were held here from the 17th century until the Hungarian Reform Era, and has been home to many Hungarian, German and Slovak historical figures. Today Bratislava is the political, cultural and economic centre of Slovakia. It is the seat of the Slovak president, the parliament and the Slovak Executive. It has several universities, and many museums, theatres, galleries and other cultural and educational institutions. Many of Slovakia's large businesses and financial institutions have headquarters there. In 2017, Bratislava was ranked as the third richest region of the European Union by GDP (PPP) per capita (after Hamburg and Luxembourg City). GDP at purchasing power parity is about three times higher than in other Slovak regions. Bratislava receives around 1 million tourists every year.

Source: Wikipedia